The need for a complex systems model of evidence for public health

Using system dynamics modeling approach to strengthen health systems to combat cancer: a systematic literature review

AIM

Dynamic cancer control is a current health system priority, yet methods for achieving it are lacking. This study aims to review the application of system dynamics modeling (SDM) on cancer control and evaluate the research quality.

METHODS

Articles were searched in PubMed, Web of Science, and Scopus from the inception of the study to 15 November 2023. Inclusion criteria were English original studies focusing on cancer control with SDM methodology, including prevention, early detection, diagnosis and treatment, and palliative care. Exclusion criteria were non-original research, and studies lacking SDM focus. Analysis involved categorization of studies and extraction of relevant data to answer the research question, ensuring a comprehensive synthesis of the field. Quality assessment was used to evaluate the SDM for cancer control.

RESULTS

Sixteen studies were included in this systematic review predominantly from the United States (7, 43.75%), with a focus on breast cancer research (5, 31.25%). Studies were categorized by WHO cancer control modules, and some studies may contribute to multiple modules. The results showed that included studies comprised two focused on prevention (1.25%), ten on early detection (62.50%), six on diagnosis and treatment (37.50%), with none addressing palliative care. Seven studies presented a complete SDM process, among which nine developed causal loop diagrams for conceptual models, ten utilized stock-flow charts to develop computational models, and thirteen conducted simulations.

LIMITATIONS

This review's macrofocus on SDM in cancer control missed detailed methodological analysis. The limited number of studies and lack of stage-specific intervention comparisons limit comprehensiveness. Detailed analysis of SDM construction was also not conducted, potentially overlooking nuances in cancer control strategies.

CONCLUSION

SDM in cancer control is underutilized, focusing mainly on early detection and treatment. Inconsistencies suggest a need for standardized SDM approaches. Future research should expand SDM's application and integrate it into cancer control strategies.

Parallel systems in healthcare: Addressing Indigenous health equity in Canada

The Canadian public healthcare system faces significant challenges in performance. While the formal healthcare system addresses funding, access and policy, there is a critical need to prioritise the informal system of community-oriented networks. This integration aligns with the World Health Organization's primary health care approach, emphasising a whole-of-society strategy for health equity. Canada's healthcare, harmonised through the Canada Health Act of 1984, focuses on need over ability to pay. Despite successes, the system struggles with social determinants of health and widening health inequities, especially among Indigenous peoples. Historical policies of forced assimilation have led to poor health outcomes and lower life expectancies for Indigenous populations. The Truth and Reconciliation Commission's Calls to Action stress removing barriers at multiple levels to improve Indigenous health. Indigenous perspectives on health, emphasising holistic wellness, contrast with Western healthcare's acute-illness focus. The emergence of parallel systems, informal networks within healthcare, reflects dissatisfaction with traditional approaches. Recognising the parallel system within Indigenous health, as proposed, can transform healthcare to better meet population needs. Systems mapping of Indigenous PHC in Alberta revealed numerous entities providing healthcare access, highlighting the importance of adequately funding and integrating these parallel systems to advance health equity.

Developing and implementing whole systems approaches to reduce inequalities in childhood obesity: A mixed methods study in Dundee, Scotland

Background

UK local authorities are developing and implementing Whole Systems Approaches to childhood obesity to tackle persistent and complex health inequalities. However, there is a lack of research on the practical application of these approaches. This paper reports on findings of a study into the initial implementation of this approach in Dundee, Scotland.

Study design/methods

We applied a mixed methods research design: 1) semi-structured interviews (n = 9) with partnership members; 2) training members as peer researchers to interview their wider networks; n = 17); 3) an online survey among wider stakeholders (n = 27); and 4) two action learning sets with decision makers. Interview data was analysed using thematic framework analysis and survey data was analysed using descriptive statistics.

Results

Dundee stakeholders stated that they had good knowledge of childhood obesity prevention efforts, but their engagement with working groups around identified priority themes was still limited, due to a lack of awareness about existing structures and knowledge about sustainable, impactful strategies, which were not always well-aligned between key organisations.

Conclusions

Our findings extend current literature on facilitators for Whole Systems Approaches in public health by highlighting that understanding of strategies and wider structures are crucial to build capacity and maintain engagement to address inequalities. We identified an ongoing need for targeted communication and diverse involvement opportunities for different stakeholder groups.

Applying a participatory system dynamics approach to childhood overweight and obesity in the local context: reflections from the LIKE project

BACKGROUND

Methods based in system dynamics (SD) have gained prominence within public health research in recent years. SD is grounded in theory and explains how central principles, such as adaptation, dynamics and emergence can be used to understand and/or change complex systems. To date, few examples exist where this theory has been applied consistently in a prevention approach in a local context. This study aimed to reflect upon the application of theoretical SD principles in context of the Lifestyle Innovations Based on Youth Knowledge and Experience (LIKE) project.

METHODS

A multi-methods qualitative evaluation was conducted using the LIKE project, situated in Amsterdam, the Netherlands, as a case study. LIKE applied a participatory system dynamics approach for obesity prevention in youth, throughout the project during a time period of 6 years (2017-2023). Data collection included document reviews, a Ripple Effects Mapping workshop, and semi-structured interviews with involved stakeholders, followed by in-depth reflective analysis.

RESULTS

We identify three key lessons combining theory and practice: (1) theory: interdependency programme and context; lesson: avoid becoming overly focused on achieving a complete understanding of the system related to the topic under study (for example, obesity). Instead, ensure sufficient attention is given to comprehending the dynamics of the local context, including existing initiatives and policy processes; (2) theory: dynamic and adaptive character; lesson: while the ability to encompass real-world dynamics is a foundational strength of system dynamics theory, its practical application can be constrained by more static elements, such as budget planning, and the need for clearly defined roles and responsibilities; and (3) theory: strong governance; lesson: SD projects require strong governance including strategic planning and enduring commitment, but in the absence of clear milestones or measurable impact on the short term.

CONCLUSIONS

Applying SD principles in practice requires a collective shift in thinking and working for all parties involved. Challenges in particular relate to the many uncertainties that arise whereby everything continues to change over time, including the focus of the system under study; relevant stakeholders; and momentum for change. This necessitates strategies different from our accustomed linear research working practices, shifting instead towards more iterative approaches that accommodate complexity and uncertainty.

The complexity of pharmaceutical expenditures across U.S. states

Understanding the complexity of pharmaceutical expenditures across U.S. states is critical for designing efficient healthcare policies and ensuring equitable drug access. This study applies network-based economic complexity methods to analyze state-level Medicaid drug spending, leveraging Medicaid State Drug Utilization Data (SDUD) from 2018 to 2024. Using Revealed Comparative Advantage (RCA) and the Method of Reflections, we quantify the sophistication of pharmaceutical consumption and identify structural inefficiencies in drug reimbursement policies. Our findings reveal substantial heterogeneity in pharmaceutical complexity across states, with highly diversified markets in states like California and Texas, while others, such as Wyoming and West Virginia, exhibit lower complexity due to restrictive formulary policies and healthcare infrastructure limitations. A 15% decline in network density over the study period suggests consolidation in reimbursement practices, influenced by regulatory interventions and cost-containment strategies. Additionally, Medicaid expansion states show a 20% increase in prescription utilization, particularly for antiviral and mental health medications. Null model comparisons highlight systematic deviations from expected expenditure patterns, with states like Arkansas and Nebraska showing lower-than-expected pharmaceutical embeddedness, whereas Massachusetts and California appear more integrated than network models predict. These findings suggest that state-specific policies, provider behavior, and market dynamics significantly shape pharmaceutical expenditures beyond structural network constraints, as well as they offer significant implications for policymakers and healthcare providers seeking to balance cost efficiency with equitable medication distribution.

Innovative epidemiology instruction for promoting population health thinking in occupational therapy doctoral students

PURPOSE

Recent shifts toward population-based health care and research in health science training programs are vital to reducing health disparities, although students need stronger education in this area. This study aimed to determine if innovative epidemiology research instruction is associated with improved science literacy skills, a core objective of population health curricula, for occupational therapy doctoral students.

METHODS

We used the Test of Scientific Literacy Skills (TOSLS) to determine change in student science literacy skills based on change in performance from baseline. Multilevel repeated measures models were run clustering by student and cohort, adjusted for demographics and prior research courses.

RESULTS

The sample included 166 students (91 % female, 57 % Non-Hispanic White, 14 % Hispanic, 19 % Non-Hispanic Black, 10 % Asian; 83 % ≤25 years old). Model estimates showed improvements in science literacy skills (β=0.39 [95 %CI:0.10, 0.67]) relative to baseline. Interaction models showed greater improvements from baseline for students who identified as Hispanic (β=0.82 [95 %CI:0.10, 1.63]) and Non-Hispanic White (β=0.55 [95 %CI:0.16, 0.94]). Additional interaction models did not show differences in the time-TOSLS association by student characteristics.

CONCLUSIONS

Innovative epidemiology instruction may be an appropriate method for supporting health sciences student development of science literacy skills to foster population health thinking, research, and practice.

Within-laboratory SARS-CoV-2 real time PCR testing operations in Nepal: a simulation-based analysis

Background

COVID-19 has challenged entire health systems, including laboratories. To address the increasing demand for tests to inform the epidemiology of the disease and for case management purposes, many countries made significant investments to rapidly expand laboratory capacity for detecting SARS-CoV-2. In this study, we used a simulated laboratory environment, based on a model of operating laboratories in Nepal, to identify opportunities for improvement.

Methods

We developed a discrete event simulation (DES) model, based on data from and in collaboration with Nepali health authorities, to analyse laboratory operations in Nepal. We used a series of "what-if" scenarios under different levels of testing demand and staffing to investigate bottlenecks in the processing of COVID-19 samples in a simulated laboratory environment, assess the impact of potential reagent shortages and increased automation, and more generally, explore the key factors that drive the performance and resilience of the testing system.

Findings

Suboptimal staff allocation and scheduling can limit the timely return of laboratory results; however, better staff allocation can mitigate bottlenecks and reduce the impact of reagent shortages. For example, when the demand is 720 samples per day and seven staff members are on duty, adding one additional staff member improves reporting time (reduction from 48 h to approximately 32 h). However, changes in scheduling can increase the average time to return the results to over 200 h. A one-day reagent shortage appears to have minimal impact, but a delay of five days significantly increases the reporting time, reaching nearly 150 h. Increasing automation or better process coordination for sample registration can also lead to better performance, reducing the average reporting time from over 60 h to just under 24 h.

Interpretation

Our findings identify important bottlenecks and challenges, along with ways to address them, and thus provide important lessons for improving disease testing operations for this and future pandemics.

Funding

WHO Special Programme for Research and Training in Tropical Diseases (TDR).

Detection of potential causal pathways among social determinants of health: A data-informed framework

INTRODUCTION

Understanding social determinants of health (SDOH) as a complex system is necessary for designing effective public health interventions. Traditional expert-driven approaches to mapping SDOH relationships, when used in isolation, are susceptible to subjective biases, incomplete knowledge, and inconsistencies across different domains of expertise. Additionally, SDOH variables often contain overlapping information, making it difficult to isolate unique SDOH constructs. A data-driven approach integrating dimensionality reduction and causal discovery can provide a more objective framework for identifying and mapping SDOH factors within a causal system. The data-driven method may serve as a starting point to overcome potential research biases in the development of causal structures.

METHODS

An observational study was conducted using census tract-level SDOH data from the 2020 Agency for Healthcare Research and Quality (AHRQ) database. Principal Component Analysis (PCA) was applied to derive latent constructs from 157 SDOH variables across 85,528 U.S. census tracts. The Greedy Equivalence Search (GES) algorithm was then used to identify dominant causal pathways between these constructs.

RESULTS

PCA-derived components explained substantial variance within each domain, with food access (71.1 %) and income (50.0 %) explaining the most within-domain variance. The causal graph revealed economic stability as a central determinant influencing education, employment, housing, and healthcare access. Education, access to care, and access to technology mediated many pathways.

DISCUSSION

Findings highlight the interconnected nature of SDOH, emphasizing financial stability as a foundational determinant. The role of digital equity in health outcomes is increasingly significant. The data-driven approach may serve as an important tool to support researchers in the mapping of SDOH causal structures.

PUBLIC HEALTH IMPLICATIONS

This study demonstrates the utility of combining PCA and GES to uncover causal pathways among SDOH constructs. Developing causal systems using data-driven methods provides an enhanced method for conducting public health assessments, identify optimal intervention points, and informing policy development.

Health in All Networks Simulator: mixed-methods protocol to test social network interventions for resilience, health and well-being of adults in Amsterdam

BACKGROUND

Social networks are an important, although overlooked, component of community-based health promotion. Advances in social network research have highlighted different social network intervention (SNI) strategies to improve community-based health promotion. The aim of this project is to collaborate with community and policy stakeholders to explore how to best apply these SNI strategies to improve the resilience, health and well-being of adults in Amsterdam, and more broadly in the Netherlands.

METHODS AND ANALYSIS

To this end, we will collaboratively develop an intervention planning tool called the 'Health in All Networks Simulator (HANS)'. This tool will be capable of virtually testing different SNI strategies and forecasting their possible impact on resilience, health and well-being. Taking a mixed-methods approach consisting of a combination of interviews, group model building workshops and agent-based modelling with members of two communities in Amsterdam and policy stakeholders, we will foster a shared learning process while ensuring ownership and relevance of HANS to ongoing community-based health promotion practice.

ETHICS AND DISSEMINATION

The research project has been approved by the research ethics committee of Wageningen University (approval numbers: 2024-039; 2024-226). HANS will be shared directly with stakeholders. The results will be made available to the public via open-access publications and conferences.

Understanding healthcare demand and supply through causal loop diagrams and system archetypes: policy implications for kidney replacement therapy in Thailand

BACKGROUND

Systems thinking approaches can determine system interdependencies to guide effective policymaking but have been underutilised in health policymaking, particularly for policies related to access and delivery of health services. In Thailand, a policy changing access to dialysis services for patients with kidney failure in 2022 had resulted in an unexpected surge in patients, mortality rate, and budget overspend. This study applied systems thinking to characterise the dynamics underlying the unforeseen impact of the 2022 policy, in order to propose context-specific policy interventions.

METHODS

We developed a causal loop diagram through iterative stakeholder engagement, to understand the drivers for supply and demand of dialysis under the 2022 policy in Thailand. Since systems thinking was considered a new tool for policymaking, we used system archetypes as a means by which to collapse down the complexity of causal loop diagrams into simple narratives for policymakers. Confidence-building (validation) was conducted through triangulation across data sources and steps to facilitate stakeholder critique throughout the process.

RESULTS

Chronic underinvestment in peritoneal dialysis had failed to capitalise on improvements in expertise and quality of services, while a series of short-term measures to overcome constraints in haemodialysis supply had unintentionally increased haemodialysis demand in the long-term, increasing strain on the healthcare system. By applying generic solution archetypes, we identified a series of measures to balance demand for services with system capacity, including better alignment of incentives with health system goals, proactive planning to anticipate future supply needs, and regulatory mechanisms to moderate demand according to available supply.

CONCLUSIONS

A major implication of this research is that changes to healthcare access and delivery require multi-stakeholder engagement and whole system thinking, as even small changes can have potentially vast consequences. Applying a systems thinking lens not only communicated the reasons for unintended impact of the 2022 policy, but also identified interventions absent from the literature that were unique to the drivers of demand and supply in Thailand.

Residents' perceptions of urban densification and health - a systems dynamics approach

BACKGROUND

Little is known about residents' perceptions of urban densification and its impact on health. A participatory systems dynamics approach can help to understand residents' perspective on the complex system of interacting factors underlying urban densification and health.

METHODS

We organised group model building sessions with three groups of residents that are living in Katendrecht, a highly densifying neighbourhood in the city of Rotterdam. The groups differed by length of residence (0-5, 10-15, and > 15 years). During the sessions, in which in total 25 residents participated, factors that influence health in the context of urban densification were identified and connected in causal loop diagrams. Also, possible actions to favourably adapt the system were discussed.

RESULTS

According to the participants, densification of Katendrecht increased its attractiveness but negatively affected local social cohesion, the availability and diversity of facilities, and the accessibility of the area. The participants also did not feel sufficiently involved by local authorities in the development of the neighbourhood and argued that densification affects their mental health by increasing levels of stress and loneliness and decreasing enjoyment in living. The residents mainly mentioned actions that increase social cohesion and residential involvement in the neighbourhood's development to maintain or improve their health in the context of densification.

CONCLUSION

This study illustrated the system underlying densification and residential health as a complex interaction between social and physical factors at the individual and neighbourhood level. Taking the perspective of residents into account can help to optimize future policies and urban densification plans in such a way that they do not harm and possibly even benefit residents' health.

Development and testing of the capacity of organisations for system practices scale

BACKGROUND

Systems change approaches are increasingly adopted in public health to address complex problems. It is important that measures of systems change be developed so that the effects of systems change on health outcomes can be evaluated. Organisational practices are potential levers for systems change. However, robust measures of organisational capacity to engage in these practices are lacking. Informed by the Theory of Systems Change, we developed and tested the Capacity of Organisations for System Practices (COSP) scale. The COSP scale comprises four inter-related system practices within organisations-adaptation, alignment, collaboration and evidence-driven action and learning.

METHODS

We applied a three-stage process: (1) Item generation; (2) Scale pre-testing; and (3) Structural analyses. Item response theory tests and semantic review, together with factor analytic techniques, were applied to refine the item set and determine the scale structure.

RESULTS

An initial pool of 97 items was generated and pre-tested with six content experts and four target audience representatives. Modifications resulted in 60 items. In total, 126 participants provided data for the structural analysis. A second-order hierarchical four-factor model fit the data better than the more basic correlated factor model (Δχ2 = 1.758, p = .415). The fit indices for the final 31-item model were acceptable (RMSEA = .084, TLI = .819).

CONCLUSIONS

The COSP scale is ready for further testing to ensure construct validity, stability and utility. SO WHAT?: Once validated, the Capacity of Organisations for System Practices (COSP) scale has the potential to advance the theory and practice of systems change approaches.

Natural polysaccharides-based smart sensors for health monitoring, diagnosis and rehabilitation: A review

With the rapid growth of multi-level health needs, precise and real-time health sensing systems have become increasingly pivotal in personal health management and disease prevention. Natural polysaccharides demonstrate immense potential in healthcare sensors by leveraging their superior biocompatibility, biodegradability, environmental sustainability, as well as diverse structural designs and surface functionalities. This review begins by introducing a variety of natural polysaccharides, including cellulose, alginates, chitosan, hyaluronic acid, and starch, and analyzing their structural and functional distinctions, which offer extensive possibilities for sensor design and construction. Further, we summarize several principal sensing mechanisms, such as piezoresistivity, piezoelectricity, capacitance, triboelectricity, and hygroelectricity, which provide a theoretical and technological foundation for developing high-performance healthcare sensing devices. Additionally, the review discusses the most recent applications of natural polysaccharide-based sensors in diverse healthcare contexts, including human body motion tracking, respiratory and heartbeat monitoring, electrophysiological signal recording, body temperature variation detection, and biomarker analysis. Finally, prospective development directions are proposed, such as the integration of artificial intelligence for real-time data analysis, the design of multifunctional devices that combine sensing with therapeutic functionalities, and advancements in remote monitoring and smart wearable technologies. This review aims to provide valuable insights into the development of next-generation healthcare sensors and propose novel research directions for personalized medicine and remote health management.

[Characteristics of the "Behavioural and cultural insights (BCI)" approach in Public Health - a consensus paper of the network "Behavioural Science Connect"]

Public health interventions are often intended to make it easier for people to adopt health-related behaviours, e. g., by changing the social environment and material living conditions. With the concept of "Behavioral and Cultural Insights" (BCI), the World Health Organization (WHO) has established an approach that aims at a better understanding of health-related behaviours, in order to be able to develop corresponding public health interventions in a more targeted manner. The focus is on the empirical identification of individuals as well as cultural, social and environmental barriers to and facilitators of health behaviour.The BCI approach can be used to plan preventive measures in a more evidence-based and needs-oriented manner. To this end, the current article outlines some basic features of BCI which should be taken into account for integrating the concept into a contemporary understanding of "new public health". This includes social and individual factors influencing health as well as social inequalities in health.First, the article distinguishes the BCI concept from the approach of behavioural economics (e. g., nudging). To illustrate its potential for population health and health equity, the article then explains that BCI-based measures that (a) focus on both behaviour and environment, (b) aim at health equity, (c) are developed and implemented in a participatory manner, and (d) follow the logic of the well-established Public Health Action Cycle. For BCI, it is crucial to systematically identify and analyse the factors influencing human behaviour in everyday life. BCI-based interventions must also consider the characteristics of complex interventions and be tailored to local conditions and the cultural diversity of specific population groups.The BCI approach has many similarities with other approaches of quality-assured and needs-oriented prevention measures. The focus on a systematic identification of barriers and facilitators offers an important added value in the planning of public health measures. Research into BCI and their use in prevention should be expanded in Germany.

Next Steps in Efforts to Address the Obesity Epidemic

Obesity prevalence continues to rise globally at alarming rates, with adverse health and economic implications. In this state-of-the-art review, we provide an analysis of selected evidence about the current knowledge in the obesity literature, including a synthesis of current challenges in obesity and its determinants. In addition, we review past and current efforts to combat the obesity epidemic, highlighting both successful efforts and areas for further development. Last, we offer insights into the next steps to address the obesity epidemic and advance the field of obesity through both research and practice by (a) adopting a systems perspective, (b) fostering cross-sector and community collaborations, (c) advancing health equity, (d) narrowing the research-to-practice and research-to-policy gaps with multidisciplinary approaches, and (e) embracing complementary approaches for concurrent obesity prevention and treatment.

A System for Objectively Measuring Behavior and the Environment to Support Large-Scale Studies on Childhood Obesity

Advances in IoT technologies combined with new algorithms have enabled the collection and processing of high-rate multi-source data streams that quantify human behavior in a fine-grained level and can lead to deeper insights on individual behaviors as well as on the interplay between behaviors and the environment. In this paper, we present an integrated system that collects and extracts multiple behavioral and environmental indicators, aiming at improving public health policies for tackling obesity. Data collection takes place using passive methods based on smartphone and smartwatch applications that require minimal interaction with the user. Our goal is to present a detailed account of the design principles, the implementation processes, and the evaluation of integrated algorithms, especially given the challenges we faced, in particular (a) integrating multiple technologies, algorithms, and components under a single, unified system, and (b) large scale (Big Data) requirements. We also present evaluation results of the algorithms on datasets (public for most cases) such as an absolute error of 8-9 steps when counting steps, 0.86 F1-score for detecting visited locations, and an error of less than 12 mins for gross sleep time. Finally, we also briefly present studies that have been materialized using our system, thus demonstrating its potential value to public authorities and individual researchers.

The epidemiologic case for urban health: conceptualizing and measuring the magnitude of challenges and potential benefits

We discuss how epidemiology has been and can continue to be used to advance understanding of the links between urban areas and health informed by an existing urban-health conceptual framework. This framework considers urban areas as contexts for health, determinants of health and modifiers of health pathways, and part of a complex system that affects health. We highlight opportunities for descriptive epidemiology to inform the context of urban health, for example, by characterizing the social and physical environments that give rise to health and the actions that change those conditions. We then describe inferential tools for evaluating the impact of group-level actions (e.g., interventions, policies) on urban health, providing some examples, and describing assumptions and challenges. Finally, we discuss opportunities and challenges of applying systems thinking and methods to advance urban health. While different conceptual frames lead to different insights, each perspective demonstrates that urban health is a major and growing challenge. The effectiveness of urban health knowledge, action, and policy as the world continues to urbanize can be informed by applying and expanding upon research and surveillance methods described here.

Integration of large-scale community-developed causal loop diagrams: a Natural Language Processing approach to merging factors based on semantic similarity

BACKGROUND

Complex public health problems have been addressed in communities through systems thinking and participatory methods like Group Model Building (GMB) and Causal Loop Diagrams (CLDs) albeit with some challenges. This study aimed to explore the feasibility of Natural Language Processing (NLP) in simplifying and enhancing CLD merging processes, avoiding manual merging of factors, utilizing different semantic textual similarity models.

METHODS

The factors of thirteen CLDs from different communities in Victoria, Australia regarding the health and wellbeing of children and young people were merged using NLP with the following process: (1) extracting and preprocessing of unique factor names; (2) assessing factor similarity using various language models; (3) determining optimal merging threshold maximising the F1-score; (4) merging the factors of the 13 CLDs based on the selected threshold.

RESULTS

Overall sentence-transformer models performed better compared to word2vec, average word embeddings and Jaccard similarity. Of 161,182 comparisons, 1,123 with a score above 0.7 given by sentence-transformer models were analysed by the subject matter experts. Paraphrase-multilingual-mpnet-base-v2 had the highest F1-score of 0.68 and was used to merge the factors with a threshold of 0.75. From 592 factors, 344 were merged into 66 groups.

CONCLUSIONS

Utilizing language models facilitates identification of similar factors and has potential to aid researchers in constructing CLDs whilst reducing the time required to manually merge them. While models accurately merge synonymous or closely related factors, manual intervention may be required for specific cases.

'Soft drinks are normal': understanding the lived experiences of Dutch teenagers with respect to sugar-sweetened beverages: a qualitative context-mapping study

BACKGROUND

Despite continuing efforts to reduce teenagers' consumption of sugar-sweetened beverages (SSBs), intake remains high across the globe. Currently, we lack a holistic understanding that also includes the lived experiences of teenagers in today's online and offline environments regarding the role of SSB's. The aim of the present paper is therefore twofold: (1) to gain a holistic understanding of teenagers' perspectives, beliefs, barriers, contextual triggers and latent needs (that is, their lived experiences) in relation to SSB consumption; and (2) to explore their views about which intervention strategies would be most likely to reduce their SSB consumption.

METHODS

A qualitative context-mapping approach, including prior sensitising assignments, was used to gain in-depth insights into the lived experiences with regard to SSB consumption of teenagers attending prevocational-level secondary school (VMBO) and living in low socioeconomic position neighbourhoods in Amsterdam, the Netherlands. From March to April 2021, 48 teenagers, aged 12 to 16, took part in the study. Due to COVID-19 restrictions, data were collected partly online and partly in person. All data were coded and analysed using thematic analysis.

RESULTS

Four main themes were identified that appeared to influence the teenage SSB consumption: (1) social norms - drinking SSBs is normal; (2) attitudes and beliefs with regard to health versus enjoyment; (3) the easy availability and affordability of SSBs; and (4) intense industry marketing efforts. We additionally explored teenage views about changes most likely to reduce their SSB consumption and found that they would be receptive to population-level interventions such as taxation.

CONCLUSIONS

The study provides comprehensive insights into teenagers' lived experiences in relation to SSBs. It highlights the prominent roles of strong social norms, conflicting beliefs, and the pervasive marketing, easy availability and low prices of SSBs. This underlines the need for a systems approach, applying combinations of effective, integrated strategies that can be specifically tailored to the perspectives of today's teenagers.

Monitoring and adaptation of a system dynamics approach to prevent childhood overweight and obesity: findings from the LIKE programme

BACKGROUND

There are few examples of public health programmes rooted in system dynamics methodology. The aim of this paper was to broaden the evidence-base on the implementation and evaluation of a system dynamics programme for obesity prevention, using the Lifestyle Innovations based on youth's Knowledge and Experience (LIKE) Programme as a case study. In LIKE, system dynamics principles were operationalized around three central pillars: the action programme is (1) rooted in a system-based understanding; (2) integrated in the local context and (3) dynamic.

METHODS

This study took place in an urban setting in Amsterdam, the Netherlands, as part of the LIKE programme. The action programme consisted of establishing thematic action groups around previously identified leverage points within the system of overweight-related behaviours among adolescents. An action monitoring register was used to monitor action development and implementation, including the targeted system level. To track action implementation and adaptation over time, we conducted an in-depth evaluation using ripple effects mapping and additional interviews for three action groups. This data was analysed by performing a thematic content analysis.

RESULTS

During the 6-year course of LIKE, 63 action ideas were formulated by 12 action groups, and 22 of these actions were implemented. Most of these implemented actions targeted lower system levels. A total of 9 of the 22 implemented actions were incorporated in existing initiatives. We observed that operationalization of system dynamics principles influenced the form of the action programme. Action ideas were dynamic in the sense that they changed over time or were abandoned because of growing system insights and/or factors within the wider context. This required shifting the focus from individual actions to the programme as a whole and formulating action ideas in terms of their function in changing the system, instead of on its form.

CONCLUSIONS

Using LIKE as a case study, this study provides an example of the output of a system dynamics action programme. We show how leverage points can be used as a starting point to develop action ideas that target lower and higher system levels. This demands monitoring and evaluation that facilitates continuous customization of the programme.

Using natural experiments to evaluate population health interventions: a framework for producers and users of evidence

Background

There has been a substantial increase in the conduct of natural experimental evaluations in the last 10 years. This has been driven by advances in methodology, greater availability of large routinely collected datasets, and a rise in demand for evidence about the impacts of upstream population health interventions. It is important that researchers, practitioners, commissioners, and users of intervention research are aware of the recent developments. This new framework updates and extends existing Medical Research Council guidance for using natural experiments to evaluate population health interventions.

Methods

The framework was developed with input from three international workshops and an online consultation with researchers, journal editors, funding representatives, and individuals with experience of using and commissioning natural experimental evaluations. The project team comprised researchers with expertise in natural experimental evaluations. The project had a funder-assigned oversight group and an advisory group of independent experts.

Results

The framework defines key concepts and provides an overview of recent advances in designing and planning evaluations of natural experiments, including the relevance of a systems perspective, mixed methods and stakeholder involvement throughout the process. It provides an overview of the strengths, weaknesses, applicability and limitations of the range of methods now available, identifies issues of infrastructure and data governance, and provides good practice considerations.

Limitations

The framework does not provide detailed information for the substantial volume of themes and material covered, rather an overview of key issues to help the conduct and use of natural experimental evaluations.

Conclusion

This updated and extended framework provides an integrated guide to the use of natural experimental methods to evaluate population health interventions. The framework provides a range of tools to support its use and detailed, evidence-informed recommendations for researchers, funders, publishers, and users of evidence.

Study registration

This methodological project was not registered.

Funding

This project was jointly funded by the Medical Research Council (MRC) and National Institute for Health and Care Research (NIHR), with project reference MC_PC_21009. The work is published in full in Public Health Research; Vol. 13, No. 3.

Adopting a complex systems approach to functional ageing: bridging the gap between gerontological theory and empirical research

Functional ageing, related to but distinct from biological and environmental systems, is defined as the changes in physical, psychological, cognitive, and social functioning, as well as behavioural factors of individuals as they age. In this Personal View, we propose that a complex systems perspective to functional ageing can show how outcomes such as quality of life and longevity, and success in prevention and treatment, emerge from dynamic interactions among these domains, rather than from single causes. We support this view in three ways. First, we explain how three key principles of complex systems science-namely, resilience, non-linearity, and heterogeneity-apply to functional ageing. Second, we show how established gerontological theories and geriatric models align with these principles. Third, we illustrate the use of novel methodological tools available from complex systems science for studying functional ageing. Finally, we offer a glossary of key concepts and recommendations for researchers to adopt this perspective in future studies on functional ageing.

Public Health Workforce Professional Development Analysis: A Human-Systems Integration for Healthy Communities

Objectives

The healthcare landscape is challenged by emerging and severe public health threats, and fast shifting priorities. There is an urgent need to build public health workforce capacity to enable rapid adaptation and effective responses to these threats. We outline a whole system's learning approach for analyzing public health systems in collaboration with public health leaders.

Methods

The project included: i) a system's analysis involving a cross-sectional mixed methods approach including a quantitative investigation, interviews and focus groups of leading representatives and students from five higher education institutions providing public health training, 49 managers, and 31 stakeholders from lead public health organizations; ii) develop and implement training interventions, involving human factors tools for evaluating and developing actionable solutions.

Results

We developed and implemented three interventions: 1) An online user interface for public health professional development and collaboration; 2) A Public Health Leadership Academy; and 3) A video outreach to key stakeholders and communities using studies.

Conclusion

A holistic perspective incorporating human factors, and a systems approach provided a comprehensive understanding and approch towards the public health workforce while identifying leverage points for durable improvement.

Validation of a Novel Method to Evaluate Community-Based Interventions That Improve Access to Fruits and Vegetables

BACKGROUND

Current evaluation tools are inadequate for assessing the impact of small-scale interventions, such as farmer's markets or community meal programs, on fruit and vegetable consumption. This study analyzes the pilot data of a novel tool designed to evaluate community-based programs' impact on fruit and vegetable consumption. Our research addresses the gap in effective evaluation methods for dietary behaviors within underserved populations.

METHODS

The survey tool was developed through a participatory research approach involving interest holders and community members. We conducted a pilot survey across four community-based programs, validated the findings, and compared them against the data from the Behavioral Risk Factor Surveillance System.

RESULTS

This pilot survey demonstrated a high completion rate of 98.2%. Notably, 62.5% of respondents reported an increased consumption of fruits and vegetables since participating in the programs and cited cost, time, and accessibility as primary barriers to healthy eating. There is a strong, though not significant, correlation of 0.876 (p = 0.12) between the pilot data of prevalence of daily fruit and vegetable consumption and the national average.

CONCLUSION

Our findings suggest the survey tool effectively captures dietary behaviors and the influence of community-based programs. Further research is required to enhance its applicability in diverse settings and extend robust impact evaluation methods for these programs.

Exploring the value Australian community leaders see in a system dynamics model calibrated with local data: social norms and childhood obesity

OBJECTIVES

Systems approaches (SAs) seek to understand the dynamics behind system behaviour and formulate effective actions given these dynamics. In public health, SAs often rely on qualitative systems maps visualising factors and their interconnections, frequently developed through group model building. Quantitative system dynamics models (SDMs) can offer additional insights: SDMs can simulate how system behaviour would change if we were to make an adjustment to the system, in what-if scenarios. We explored what (added) value Australian community leaders involved in SAs see in an SDM for understanding a system and its behaviour.

SETTING

The Whole of Systems Trial of Prevention Strategies for Childhood Obesity (WHOSTOPS), a community-level collaboration between researchers and community leaders in South-Western Victoria, Australia.

DESIGN

We calibrated an existing small and high-level SDM with local data from the WHOSTOPS communities, so that the simulations pertained to their local context. The SDM was developed to simulate potential interventions addressing either social norms regarding body weight or individual weight-related behaviour. We presented the SDM to the community leaders via an interactive interface in an online workshop.

PARTICIPANTS

We calibrated the SDM using WHOSTOPS' baseline measurement (2015), with an 80% participation rate among eligible children (1792/2516). 11 community leaders participated in the workshop.

RESULTS

The community leaders' first impression of the SDM was that it could be a valuable additional tool, particularly because of its ability to compare what-if scenarios resembling individual vs systems perspectives, intuitive presentation of simulation results, and use of local data.

CONCLUSIONS

Our preliminary exploration showed that the small and high-level SDM, using what-if scenarios reflecting interventions on different system levels, could contribute to the understanding and communication of (community-based) SAs.

Identifying mechanisms that shape the food environment in long-term healthcare facilities in the Netherlands: a participatory system dynamics approach

BACKGROUND

Creating healthy and sustainable food environments within long-term healthcare facilities asks for a systemic approach. This study aimed to: (1) identify system dynamics underlying the food environment of long-term healthcare facilities, (2) formulate actions for changing the system to promote a healthy and sustainable food environment and (3) evaluate stakeholder perspectives about the process and progress towards action implementation up to one-year follow-up.

METHODS

A group model building (GMB) approach was used during two workshops with stakeholders of five different long-term healthcare facilities in the Netherlands. Stakeholders created a causal loop diagram (CLD) and formulated actions for change. Interviews were conducted at six- and twelve months to evaluate perspectives on the GMB process and progress towards action implementation.

RESULTS

The developed CLD consisted of 30 factors influencing the food environment in long-term healthcare facilities and four interrelated subsystems (patient; healthcare organization; national governance and policy; purchasing, procurement and budget). Stakeholders formulated 40 corresponding actions. After one year follow-up, small steps towards action implementation were observed (e.g., agenda setting, raising internal awareness, formulating plans), with several barriers hindering implementation being noted (e.g., lack of time, budget, priority).

CONCLUSIONS

This study gained a comprehensive, collectively acknowledged understanding of the system dynamics underlying the food environment in Dutch long-term healthcare institutions. The results underscore the importance of crafting a coherent set of actions that addresses various factors and underlying mechanisms to initiate systemic change. However, achieving actual system changes in long-term healthcare facilities requires prolonged efforts and overcoming barriers towards implementation.

'It's about collaboration': a whole-systems approach to understanding and promoting movement in Suffolk

BACKGROUND

Population-levels of physical activity have remained stagnant for years. Previous approaches to modify behaviour have broadly neglected the importance of whole-systems approaches. Our research aimed to (i) understand, (ii) map, (iii) identify the leverage points, and (iv) develop solutions surrounding participation in physical activity across an English rural county.

METHODS

A systems-consortium of partners from regional and local government, charities, providers, deliverers, advocacy groups, and health and social care, and public health engaged in our research, which consisted of two-phases. Within Phase 1, we used secondary data, insight-work, a narrative review, participatory workshops, and interviews in a pluralistic style to map the system-representing physical activity. Phase 2 began with an initial analysis using markers from social network analysis and the Action Scales Model. This analysis informed a participatory workshop, to identify leverage points, and develop solutions for change within the county.

RESULTS

The systems-map is constructed from biological, financial, and psychological individual factors, interpersonal factors, systems partners, built, natural and social environmental factors, and policy and structural factors. Our initial analysis found 13 leverage points to review within our participatory workshop. When appraised by the group, (i) local governing policies, (ii) shared policies, strategies, vision, and working relationships, (iii) shared facilities (school, sport, community, recreation), and (iv) funding were deemed most important to change. Within group discussions, participants stressed the importance and challenges associated with shared working relationships, a collective vision, and strategy, the role of funding, and management of resources. Actions to leverage change included raising awareness with partners beyond the system, sharing policies, resources, insight, evidence, and capacity, and collaborating to co-produce a collective vision and strategy.

CONCLUSIONS

Our findings highlight the importance and provide insight into the early phase of a whole-systems approach to promoting physical activity. Our whole-systems approach within Suffolk needs to consider methods to (i) grow and maintain the systems-consortium, (ii) create a sustainable means to map the system and identify leverage points within it, and (iii) monitor and evaluate change.

Using group model building to frame the commercial determinants of dietary behaviour in adolescence - findings from online system mapping workshops with adolescents, policymakers and public health practitioners in the Southwest of England

BACKGROUND

In England, 23% of children aged 11 start their teenage years living with obesity. An adolescent living with obesity is five times more likely to live with obesity in adult life. There is limited research and policy incorporating adolescents' views on how they experience the commercial determinants of dietary behaviour and obesity, which misses an opportunity to improve services and policies that aim to influence the prevalence of childhood obesity. This study reports the findings from online Group Model Building system mapping workshops in which we explored the mechanisms by which commercial drivers influence adolescents' dietary behaviour.

METHODS

We ran a series of 3 online Group Model Building workshops with adolescents and one Group Model Building workshop with policymakers and public health practitioners. Adolescents portrayed their views on how food and beverage industries influence what they choose to buy and eat in a system map, and then proposed a set of policy actions to promote healthier food environments. We shared the system map created by adolescents with policymakers and public health practitioners to reflect on how current policy interventions match adolescents' views on the most influential factors.

RESULTS

The system map contains 37 elements connected by 70 hypothesised causal links and five feedback loops. These elements were grouped into six themes that portray the complexity of factors that influence adolescents' food choices in their physical and digital environments, disproportionately encouraging the consumption of unhealthy products. Policymakers and public health practitioners reflected on the power and the deep level of influence food companies exert on adolescents' behaviour. They recognised that the coexisting influence of food marketing and social media on mental health and body image is not well reflected in current policy and research efforts.

CONCLUSIONS

This study highlights the need for public health policymaking processes to provide youth with a space to voice influential elements and consequences, thereby co-creating policies and designing interventions to buffer risk factors and increase well-being in this critical transitional stage.

Understanding the dynamics driving obesity in socioeconomically deprived urban neighbourhoods: an expert-based systems map

BACKGROUND

Over the past decades, the prevalence of obesity among adults has rapidly increased, particularly in socioeconomically deprived urban neighbourhoods. To better understand the complex mechanisms behind this trend, we created a system map exposing the underlying system driving obesity prevalence in socioeconomically deprived urban neighbourhoods over the last three decades in the Netherlands.

METHODS

We conducted Group Model Building (GMB) sessions with a group of thirteen interdisciplinary experts to develop a Causal Loop Diagram (CLD) of the obesogenic system. Using system-based analysis, the underlying system dynamics were interpreted.

RESULTS

The CLD demonstrates the food environment, physical activity environment, socioeconomic environment and socio-political environment, and their interactions. We identified the following overarching reinforcing dynamics in the obesogenic system in socioeconomically deprived urban neighbourhoods: (1) adverse socioeconomic conditions and an unhealthy food environment reinforced each other, (2) increased social distance between social groups and adverse socioeconomic conditions reinforced each other and (3) increased social distance between institutions and communities and the normalisation of unhealthy behaviours reinforced each other. These deeper system dynamics further reinforced chronic stress, sedentary behaviour, sleeping problems, unhealthy diets and reduced physical activity over time. In turn, these dynamics led to the emergent result of rising obesity prevalence in socioeconomically deprived urban neighbourhoods over the past decades.

CONCLUSIONS

Our study sheds light on the system dynamics leading to neighbourhoods with an unhealthy food environment, challenging socioeconomic conditions, a widening distance between social groups and an infrastructure that discouraged physical activity while promoting sedentary behaviour. Our insights can form the basis for the development of an integrated approach aimed at reshaping the obesogenic system in socioeconomically deprived urban neighbourhoods.

Integrating Multi-Cancer Early Detection (MCED) Tests with Standard Cancer Screening: System Dynamics Model Development and Feasibility Testing

BACKGROUND

Cancer screening plays a critical role in early disease detection and improving outcomes. In Australia, established screening protocols for colorectal, breast and cervical cancer have significantly contributed to timely cancer detection. However, the recent introduction of multi-cancer early detection (MCED) tests arguably can disrupt current screening, yet the extent to which these tests provide additional benefits remains uncertain. We present the development and initial validation of a system dynamics (SD) model that estimates the additional cancer detections and costs associated with MCED tests.

AIM

This article describes the development of a simulation model built to evaluate the additional patient diagnoses and the economic impact of incorporating MCED testing alongside Australia's well-established standard of care (SOC) screening programs for colorectal, breast, cervical and lung cancers. The model was designed to estimate the additional number of patients diagnosed at each cancer stage (stage I, II, III, IV, or unknown) and the associated costs. This simulation model allows for the analysis of multiple scenarios under a plausible set of assumptions regarding population-level participation rates.

METHODS

An SD model was developed to represent the existing SOC national cancer screening pathways and to integrate potential clinical pathways that could be introduced by MCED tests. The SD model was built to investigate three scenarios for the use of MCED testing: firstly, to explore the viability of MCED testing as a substitute among individuals who are not opting for SOC screening for any reason; secondly, to implement MCED testing exclusively for individuals ineligible for SOC screening, yet have high-risk characteristics; and thirdly, to employ MCED testing after SOC screening to serve as a triaging/confirmatory tool for individuals receiving inconclusive test results. The three primary scenarios were constructed by varying diagnostic accuracy and uptake rates of MCED tests.

DISCUSSION

The clinical utility and outcomes of MCED testing for screening and early detection still lack comprehensive evidence. Nonetheless, this simulation model facilitates a thorough analysis of MCED tests within the Australian healthcare context, providing insights into potential additional detections and costs to the healthcare system, which may help prioritise future evidence development. The adaptable yet novel SD model presented herein is anticipated to be of considerable interest to industry, policymakers, consumers and clinicians involved in informing clinical and economic decisions regarding integrating MCED tests as cancer screening and early detection tools. The expected results of applying this SD model will determine whether using MCED testing in conjunction with SOC screening offers any potential benefits, possibly guiding policy decisions and clinical practices towards the adoption of MCED tests.

UK policymaker and expert perspectives on the smoke-free generation policy: a qualitative study

Introduction

The UK smoke-free generation (SFG) proposal seeks to ban the sale of tobacco products to those born in or after 2009. There is substantial evidence for the benefits of raising the age of sale of tobacco but, despite several governments proposing SFG, the policy has faced significant challenge and has not been implemented at nation-state level. This study explores the context in which UK may be the first country to introduce SFG, identifies potential barriers and facilitators to SFG implementation and outlines possible approaches to SFG policy design.

Methods

We conducted 19 qualitative semistructured interviews with policymakers and health leaders in England, Scotland and Wales, including politicians, public health experts, academics, trading standards experts (responsible in UK for enforcing age restrictions on products), clinicians and civil society (charity sector) representatives. Data were analysed through Kingdon's three policy streams (problem, policy and political) and organised using the framework approach.

Results

Participants conceptualised SFG as both addressing youth tobacco initiation and shifting societal norms. They agreed that all tobacco products should be included but had differing views on including e-cigarettes. Opinions on enforcement varied. Some believed minimal enforcement would suffice due to anticipated compliance, while others stressed the need for strong enforcement. All agreed enforcement should target retailers, not individuals. Politically, participants noted the rapid shift from advocates supporting Tobacco 21 to embracing SFG after government endorsement. Cohesive public health advocacy, maintaining cross-party support and public opinion and developing broader tobacco control policies were considerations for successful implementation.

Conclusions

Widespread support for SFG across expert, political and public opinion provides a strong foundation for its passing into law. UK public health actors swiftly took advantage of the opening of a tobacco control policy window. Those implementing SFG must carefully consider product coverage and its approach to enforcement.

Using social network analysis to identify influential community organizations

BACKGROUND

We used a social network approach to identify influential community organizations within integrated public health networks in three regions in Texas, US: Houston/Harris County, Cameron County, and Northeast Texas. The study aimed to understand how network structures influence organizational performance in COVID-19 response.

METHODS

In collaboration with community partners in each region, we administered a snowball sampling network data collection. Initial seed sets for the regions of 23, 25, and 55 organizations identified other organizations that then responded to the survey, which expanded the sets to 268, 145, and 138, respectively. Principal component analysis (PCA) identified key network structures-centrality and brokerage-and we introduced two network-based performance measures: Fulfillment Rate (FR), which measures securing needed resources, and Provision Rate (PR), which measures providing resources to others. We tested hypotheses to examine the associations between these network structures and organizational performance.

FINDINGS

Centrality consistently emerged as a predictor of organizational performance across all three regions. Community organizations that are more centrally positioned, rather than broker organizations, play a critical role in meeting resource needs and providing services to other organizations. Centrally positioned organizations conducted more COVID-19 tests, whereas brokers administered fewer vaccines.

INTERPRETATIONS

This study suggests that public health interventions should prioritize central organizations for resource allocation and distribution. Our network-based performance metrics offer new avenues for evaluating organizational effectiveness in networked public health systems, with broader applicability to future crises and public health planning.

Early COVID-19 Pandemic Preparedness: Informing Public Health Interventions and Hospital Capacity Planning Through Participatory Hybrid Simulation Modeling

We engaged with health sector stakeholders and public health professionals within the health system through a participatory modeling approach to support policy-making in the early COVID-19 pandemic in Saskatchewan, Canada. The objective was to use simulation modeling to guide the implementation of public health measures and short-term hospital capacity planning to mitigate the disease burden from March to June 2020. We developed a hybrid simulation model combining System Dynamics (SD), discrete-event simulation (DES), and agent-based modeling (ABM). SD models the population-level transmission of COVID-19, ABM simulates individual-level disease progression and contact tracing intervention, and DES captures COVID-19-related hospital patient flow. We examined the impact of mixed mitigation strategies-physical distancing, testing, conventional and digital contact tracing-on COVID-19 transmission and hospital capacity for a worst-case scenario. Modeling results showed that enhanced contact tracing with mass testing in the early pandemic could significantly reduce transmission, mortality, and the peak census of hospital beds and intensive care beds. Using a participatory modeling approach, we not only directly informed policy-making on contact tracing interventions and hospital surge capacity planning for COVID-19 but also helped validate the effectiveness of the interventions adopted by the provincial government. We conclude with a discussion on lessons learned and the novelty of our hybrid approach.

Unintended consequences of measures implemented in the school setting to contain the COVID-19 pandemic: a scoping review

BACKGROUND

Throughout the COVID-19 pandemic, schools were a key setting for intervening with public health and social measures (PHSM) to reduce transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Consequently, there is a need to assess the varied unintended consequences associated with PHSM implemented in the school setting, for students, teachers, and school staff, as well as for families and the wider community. This is an update of a Cochrane scoping review first published in 2022.

OBJECTIVES

To comprehensively identify and summarise the published literature on the unintended consequences of public health and social measures implemented in the school setting to reduce the spread of SARS-CoV-2. This will serve to identify critical knowledge gaps to inform future primary research and systematic reviews. It may also serve as a resource for future pandemic management.

SEARCH METHODS

We searched MEDLINE, Embase, CENTRAL, PsycINFO, ERIC, and Web of Science on 5 and 6 January 2023. We also searched two COVID-19-specific databases (Cochrane COVID-19 Study Register and WHO COVID-19 Global literature on coronavirus disease). Finally, we reviewed the included studies of all relevant systematic reviews and guidelines identified through the searches.

SELECTION CRITERIA

We included studies that empirically assessed the impact of PHSM implemented in the school setting to reduce the spread of SARS-CoV-2. We imposed no restrictions with regard to the types of populations and specific interventions. Outcomes of interest were consequences that were measured or experienced, but not anticipated consequences. This review focused on real-world evidence: empirical quantitative, qualitative, and mixed-method studies were eligible for inclusion, but modelling studies were ineligible.

DATA COLLECTION AND ANALYSIS

The review was guided by a logic model. In line with the latest Cochrane effectiveness review of school measures to contain COVID-19 and a conceptual framework of PHSM, this logic model distinguishes between measures to make contacts safer (related to individual protection and the physical environment), measures to reduce contacts (related to social interactions, movement, and services) and surveillance and response measures. Unintended consequences comprise the following categories: health and well-being, health system and social welfare services, human and fundamental rights, acceptability and adherence, equality and equity, social and institutional, economic and resource, and ecological. The review team screened all titles and abstracts, then potentially eligible full-text articles, in duplicate. Across the included studies, we summarised and presented types of measures, consequences, and study designs using the predefined categories of the logic model, while allowing for emerging categories.

MAIN RESULTS

We included 60 studies (57 new to this update) from 25 countries. There were 31 quantitative studies, 17 qualitative studies, and 12 mixed-method studies. Most targeted either students (26 studies), teachers and school staff (11 studies), or students and school staff (12 studies). Others evaluated measures aimed at parents (2 studies), staff and parents (1 study), students and teachers (3 studies), or the whole school (5 studies). The measures were related to individual protection (26 studies), the physical environment (20 studies), social interactions (25 studies), services (1 study), movement (3 studies), surveillance (9 studies) and response (7 studies). Nine studies evaluated the combined effect of multiple measures. The main consequences assessed were from the categories health and well-being (29 studies), acceptability and adherence (31 studies), and social and institutional (23 studies). Fewer studies covered consequences from the categories equality and equity (2 studies), economic and resource (7 studies), and ecological (1 study). No studies examined consequences for the health system and social welfare services or for human and fundamental rights.

AUTHORS' CONCLUSIONS

This scoping review provides an overview of the evidence on the unintended consequences of PHSM implemented in the school setting to reduce the spread of SARS-CoV-2. The 60 included studies describe a broad body of evidence and cover a range of measures and unintended consequences, primarily consequences for health and well-being, acceptability and adherence, social and institutional aspects, and economic aspects. The main gaps identified relate to consequences of school measures for the health system and social welfare services, human and fundamental rights, equality and equity, and the environment. Further research is needed to fill these gaps, making use of diverse methodological approaches. Future studies should explore unintended consequences - whether beneficial or harmful - in more depth and over longer time periods, in different population groups, and across different contexts. A more robust evidence base could inform and facilitate decisions about whether, how, and when to implement or terminate COVID-19 risk mitigation measures in school settings, and how to counter negative unintended consequences.

FUNDING

This publication was partially funded by the German Federal Ministry of Education and Research (BMBF) within the Network of University Medicine (NUM) 1.0, Grant No. 01KX2021 in the context of the project CEOsys, and NUM 2.0, Grant No. 01KX2121 in the context of the projects PREPARED and coverCHILD.

REGISTRATION

The protocol is registered on the Open Science Framework (osf.io/bsxh8). The previous review is published in the Cochrane Library (10.1002/14651858.CD015397).

Analysis of how a complex systems perspective is applied in studies on socioeconomic inequalities in health and health behaviour-a call for reporting guidelines

BACKGROUND

A complex systems perspective is gaining popularity in research on socioeconomic inequalities in health and health behaviour, though there may be a gap between its popularity and the way it is implemented. Building on our recent systematic scoping review, we aim to analyse the application of and reporting on complex systems methods in the literature on socioeconomic inequalities in health and health behaviour.

METHODS

Selected methods and results from the review are presented as a basis for in-depth critical reflection. A traffic light-based instrument was used to assess the extent to which eight key concepts of a complex systems perspective (e.g. feedback loops) were applied. Study characteristics related to the applied value of the models were also extracted, including the model evidence base, the depiction of the model structure, and which characteristics of model relationships (e.g. polarity) were reported on.

RESULTS

Studies that applied more key concepts of a complex systems perspective were also more likely to report the direction and polarity of relationships. The system paradigm, its deepest held beliefs, is seldom identified but may be key to recognize when designing interventions. A clear, complete depiction of the full model structure is also needed to convey the functioning of a complex system. We recommend that authors include these characteristics and level of detail in their reporting.

CONCLUSIONS

Above all, we call for the development of reporting guidelines to increase the transparency and applied value of complex systems models on socioeconomic inequalities in health, health behaviour and beyond.

Mobile health clinics for distribution of vaccinations to underserved communities during health emergencies: A COVID-19 case study

Objectives

Mobile health clinics (MHCs) effectively provide healthcare to underserved communities. However, their application during health emergencies is understudied. We described the implementation of an MHC program delivering vaccinations during the COVID-19 pandemic, examined the program's reach to medically underserved communities, and investigated characteristics of vaccination uptake in order to inform the utility of MHCs during health emergencies.

Study design

The study observed COVID-19 MHC vaccination rates and factors associated with uptake between February 20th, 2021, and February 17th, 2022.

Methods

Prisma Health deployed six MHCs to underserved communities. We described the characteristics of individuals who utilized the MHCs and evaluated census tract-level community factors associated with use of the MHCs through generalized linear mixed effects models.

Results

The MHCs conducted 260 visits at 149 unique sites in South Carolina, providing 12,102 vaccine doses to 8545 individuals: 2890 received a partial dose, 4355 received a primary series, and 1300 received a booster dose. Among individuals utilizing the MHC, the median age was 42 years (IQR: 22-58), 44.0 % were Black, 49.2 % were male, and 44.2 % were uninsured. Black, Hispanic, and uninsured individuals were significantly more likely to utilize MHC services for COVID-19 vaccination. During periods when vaccines were limited, MHC utilization was significantly greater in communities facing access barriers to healthcare.

Conclusions

The high COVID-19 vaccination uptake at MHCs demonstrated that the MHC framework is an effective and acceptable intervention among medically underserved populations during health emergencies, especially when resources are scarce. The identified factors associated with vaccination uptake demonstrated that the MHCs had the greatest impact in higher-risk communities and can be used to inform allocation of such field-level interventions in future health emergencies.

Learning from over ten years of implementing the One Health approach in the Democratic Republic of Congo: A qualitative study

Background

The Democratic Republic of Congo (DRC) has faced emerging infectious diseases such as Ebola, Mpox and Yellow fever, and antimicrobial resistance is a growing concern. To address these issues, in 2011 the country embarked on implementing the One Health (OH) approach at the national and provincial levels. This study investigates OH institutionalization and implementation in the DRC, describes the process of OH decentralization, and identifies the opportunities and challenges of sustaining these efforts.

Methods

We conducted a qualitative study based on literature, document review and key informant interviews. The literature search targeted PubMed, Google Scholar and the document depository of the national One Health platform (NOHP). Key informant identified at the national level included ministry representatives, OH platform members and donors supporting OH implementation. These interviews were conducted in-person and online, recorded, transcribed, and imported into Dedoose software (version 9.2.006) for coding. Content analysis was performed to identify activities, processes, and achievements during the implementation of OH in DRC.

Findings

Results of the literature and document review (n = 72) and analysis of stakeholder interviews (n = 24) indicate that a national OH platform, initiated in 2011, is hosted at the Ministry of Higher Education and coordinates other sectors. It comprises governmental departments, academic institutions, and civil society organizations working at the human, animal, and environment sectors. The governance structure includes a national coordinator, a permanent secretariat, technical working groups, and subnational entities at provincial and territorial levels. Following the establishment of the national OH platform, a structured process foresees to facilitate OH implementation at the provincial and territorial levels. Achievements up to today include the development of training programs, establishment of OH committees in some provinces, assessments of workforce needs, formulation of a national strategy, development of governance manuals, and support to the Mpox response coordination.Nevertheless, OH implementation in the DRC faces challenges, including leadership tensions at the national level, inadequate domestic funding, limited training and capacity building for professionals, and insufficient infrastructure for data collection and sharing. Strengthening leadership and coordination, advocating for domestic resource mobilization, and strengthening infrastructure for data collection and sharing while ensuring equity across sectors is essential for advancing the OH agenda and ensuring its efficacy.

Interventions to improve mental health and well-being in care-experienced children and young people aged less than 25: the CHIMES systematic review

Background

Children and young people with experience of being in care (e.g. foster care, kinship care, residential care or at home with a supervision requirement order) are at higher risk of adverse mental health and well-being outcomes compared to the general population. Despite a range of policy recommendations and interventions, it is not clear what approaches are effective in the United Kingdom, or how context factors give rise to facilitators and inhibitors of implementation and acceptability.

Objectives

The CHIMES review is a complex-systems-informed mixed-method systematic review that aimed to synthesise the international evidence base for interventions addressing the mental health and well-being of care-experienced children and young people (age ≤ 25 years) and to assess the potential transportability of this evidence base to the United Kingdom context.

Data sources

We searched 16 electronic bibliographic databases and 22 websites from 1990 to May 2022. We conducted citation tracking, screened relevant systematic reviews and contacted international experts.

Method

We used a convergent synthesis design. We first constructed an evidence map to confirm review scope before undertaking method-level syntheses for outcome evaluations, process evaluations and economic evaluations. These elements were integrated into a review-level synthesis to identify potential evidence-based interventions that may progress to further development, adaptation and evaluation in the United Kingdom. We conducted stakeholder consultations to prioritise intervention theories, types and outcomes.

Results

We identified 64 interventions from 124 study reports. Interventions were primarily evaluated in the United States and targeted young people's competencies or carers' parenting practices. Meta-analysis reported limited evidence that interventions effectively improved mental health in the shorter term (0-6 months): total social, emotional and behavioural problems (d = -0.15, 95% confidence interval -0.28 to -0.02); internalising problem behaviours (d = -0.35, 95% confidence interval -0.61 to -0.08); externalising problem behaviours (d = -0.30, 95% confidence interval -0.53 to -0.08); depression and anxiety (d = -0.26, 95% confidence interval -0.40 to -0.13) and social-emotional functioning difficulties (d = -0.18, 95% confidence interval -0.31 to -0.05), but these impacts were not observed in the longer term (> 6 months). Five key context factors potentially explain challenges to implementation and acceptability: lack of system resources; the time, cognitive and emotional burden of delivery or participation; interprofessional tensions; the devaluing of young people, meaning that they felt unable to express dissatisfaction with interventions; and the devaluating of carers' expertise and needs. From the evidence, stakeholder consultation identified two priority interventions: (1) mentoring by individuals with knowledge and experience of care and (2) system and ethos change to create harmonisation between organisations and facilitate interprofessional relationships. Well-being and suicide-related behaviours are priority outcomes alongside mental health.

Limitations

The review was limited by a paucity of theory and economic evaluations, so it is unclear how interventions might function or their potential cost-effectiveness. Interventions were insufficiently described, making it challenging to map the evidence base. Outcome evaluations were poorly reported. Due to ongoing restrictions with COVID-19, stakeholder consultations were conducted later than intended with a smaller number of attendees.

Conclusions

The review identified some evidence for interventions impacting mental health in the short term. There is a lack of system-level interventions and approaches that target subjective well-being and suicide-related outcomes. Future intervention might prioritise mentoring and targeting system culture.

Study registration

This study is registered as PROSPERO CRD42020177478.

Funding

This award was funded by the National Institute for Health and Care Research (NIHR) Public Health Research programme (NIHR award ref: NIHR129113) and is published in full in Public Health Research; Vol. 12, No. 14. See the NIHR Funding and Awards website for further award information.

Industry influence on public health policy formulation in the UK: a complex systems approach

Unhealthy commodity industries (UCIs) such as tobacco, alcohol, gambling, ultra-processed food and beverage producers are known to influence policy-making to advance their interests, often to the detriment of public health goals. This study mapped the complex system underpinning UCI's influence on public health policy formulation in the UK and identified potential interventions to shift the system towards being able to better attain public health goals. We conducted a participatory systems mapping workshop with ten experts to build a causal loop diagram (CLD) and identify potential interventions to address UCI's influence on public health policy development. The resulting CLD depicts a highly interconnected and reinforcing system driving UCI's involvement in public health policy formulation across five thematic areas. Among the most connected elements were the 'dominance of market mechanisms', 'perception of partnership as good governance principle', 'industry involvement lending perceived legitimacy to the policy formulation process', 'industry is seen as part of the solution' and 'industry ties to policy-makers'. Participants identified a total of 22 interventions within this system. Analysis of the CLD and interventions identified the potential for two key paradigmatic changes in this complex system: de-normalizing the perception of unhealthy commodity industry actors as legitimate stakeholders in policy formulation; and prioritizing public health and wellbeing objectives over profit and economic gain. In order to shift the system towards better attaining public health goals, interventions should reinforce each other and be supportive of these two key paradigmatic shifts.

Incorporating Complexity and System Dynamics into Economic Modelling for Mental Health Policy and Planning

Care as usual has failed to stem the tide of mental health challenges in children and young people. Transformed models of care and prevention are required, including targeting the social determinants of mental health. Robust economic evidence is crucial to guide investment towards prioritised interventions that are effective and cost-effective to optimise health outcomes and ensure value for money. Mental healthcare and prevention exhibit the characteristics of complex dynamic systems, yet dynamic simulation modelling has to date only rarely been used to conduct economic evaluation in this area. This article proposes an integrated decision-making and planning framework for mental health that includes system dynamics modelling, cost-effectiveness analysis, and participatory model-building methods, in a circular process that is constantly reviewed and updated in a 'living model' ecosystem. We describe a case study of this approach for mental health system policy and planning that synergises the unique attributes of a system dynamics approach within the context of economic evaluation. This kind of approach can help decision makers make the most of precious, limited resources in healthcare. The application of modelling to organise and enable better responses to the youth mental health crisis offers positive benefits for individuals and their families, as well as for taxpayers.

Understanding the obesity dynamics by socioeconomic status in Colombian and Mexican cities using a system dynamics model

Purpose

This paper aims to enrich understanding of the obesity transition among socioeconomic status (SES) strata by gender and age in cities of Colombia and Mexico. The study uses harmonized data from the Salud Urbana en América Latina (SALURBAL) study.

Methods

A population-level system dynamics model was developed using 2010 and 2015 data from Colombia and 2012 and 2016 data from Mexico (national health surveys). The model simulates the prevalence of different BMI categories (i.e., not overweight, overweight, obese) stratified by gender, age, and SES, in the SALURBAL cities (aggregated to the country level) of Colombia and Mexico from 2010 to 2050. Sample sizes for Colombia in 2010 and Mexico in 2012 were 7420 and 5785 children (<5 years), 21601 and 14413 children and adolescents (5-17 years), and 46597 and 20464 adults (18-64 years), respectively. Sample sizes for Colombia in 2015 and Mexico in 2016 were 4450 and 907 children, 12468 and 2350 children and adolescents, and 90430 and 3413 adults, respectively.

Results

For men in Colombia and Mexico, the burden of obesity is projected to increase among lower SES adults over time. Colombian women show similar patterns observed in men but the burden of obesity was already greater in the lower SES groups as early as 2012. In Mexican women, the burden of obesity in 2012 is higher in the lower SES population; however, the prevalence of obesity is projected to increase at a faster rate in the higher SES population. Patterns for children aged 0-14 years differed by gender and country.

Conclusions

The model suggests that the prevalence of obesity among SES strata by age and gender in SALURBAL cities of Colombia and Mexico are likely to change over time, and predicts their possible evolution through the different stages of the obesity transition.

Impact of frailty, malnutrition and socioeconomic status on perioperative outcomes

BACKGROUND

Frailty, malnutrition and low socioeconomic status may mutually perpetuate each other in a self-reinforcing and interdependent manner. The intertwined nature of these factors may be overlooked when investigating impacts on perioperative outcomes. This study aimed to investigate the impact of frailty, malnutrition and socioeconomic status on perioperative outcomes.

METHODS

A multicentre cohort study involving six Australian tertiary hospitals was undertaken. All consecutive surgical patients who underwent an operation were included. Frailty was defined by the Hospital Frailty Risk Score, malnutrition by the Malnutrition Universal Screening Tool (MUST) and low socioeconomic status by the Index of Relative Socioeconomic Disadvantage. Linear mixed-effects and binary logistic generalised estimated equation models were performed for the outcomes: inpatient mortality, length of stay, 30-day readmission and re-operation.

RESULTS

A total of 21 976 patients were included. After controlling for confounders, malnutrition and socioeconomic status, patients at high risk of frailty have a mean hospital length of stay 3.46 times longer (mean ratio = 3.46; 95% confidence interval (CI): 3.20, 3.73; P value < .001), odds of 30-day readmission 2.4 times higher (odds ratio = 2.40; 95% CI: 2.19, 2.63; P value < .001) and odds of in-hospital mortality 12.89 times greater than patients with low risk of frailty (odds ratio = 12.89; 95% CI: 4.51, 36.69; P value < .001). Elevated MUST scores were also significantly associated with worse outcomes, but to a lesser extent. Socioeconomic status had no association with outcomes.

CONCLUSION

Perioperative risk evaluation should consider both frailty and malnutrition as separate, significant risk factors. Despite strong causal links with frailty and malnutrition, socioeconomic disadvantage is not associated with worse postoperative outcomes. Additional studies regarding the prospective identification of these patients with implementation of strategies to mitigate frailty and malnutrition and assessment of perioperative risk are required.

If things were simple, word would have gotten around. Can complexity science help us improve pediatric research?

Complexity science is a discipline which explores how complex systems behave and how we interact with them. Though it is widely implemented outside medicine, particularly in the sciences involving human behavior, but also in the natural sciences such as physics and biology, there are only a few applications within medical research. We propose that complexity science can provide new and helpful perspectives on complex pediatric medical problems. It can help us better understand complex systems and develop ways to cope with their inherent unpredictabilities. In this article, we provide a brief introduction of complexity science, explore why many medical problems can be considered 'complex', and discuss how we can apply this perspective to pediatric research. IMPACT: Current methods in pediatric research often focus on single mechanisms or interventions instead of systems, and tend to simplify complexity. This may not be appropriate. Complexity science provides a framework and a toolbox to better address complex problems. This review provides a starting point for the application of complexity science in pediatric research.

DE-PASS Best Evidence Statement (BESt): Determinants of self-report physical activity and sedentary behaviours in children in settings: A systematic review and meta-analyses

Previous physical activity interventions for children (5-12yrs) have aimed to change determinants associated with self-report physical activity behaviour (PAB) and/or sedentary behaviour (SB), however, the associations between these determinants and PAB/SB in different settings are uncertain. The present study aimed to identify modifiable determinants targeted in previous PAB/SB interventions for children. Intervention effects on the determinants and their associations with self-report PAB/SB were assessed across settings. Search of relevant interventions from pre-defined databases was conducted up to July 2023. Randomized and non-randomized controlled trials with modifiable determinants were included. Data extraction and risk of bias assessments were conducted by two independent researchers. Where data could be pooled, we performed Robust Bayesian meta-analyses. Heterogeneity, publication bias and certainty of evidence were assessed. Fifteen studies were deemed eligible to be included. Thirty-seven unique determinants within four settings were identified-school, family, school with family/home, and community with(out) other settings. Ninety-eight percent of determinants belonged to individual/interpersonal determinant categories. Narratively, intervention effects on student perception of teachers' behaviour (school), self-management, perceived barriers, external motivation, exercise intention, parental modeling on SB (school with family/home) and MVPA expectations (community) were weak to strong, however, corresponding PAB/SB change was not evident. There were negligible effects for all other determinants and the corresponding PAB/SB. Meta-analyses on self-efficacy, attitude, subjective norm and parental practice and PAB/SB in two settings showed weak to strong evidence against intervention effect, while the effect on knowledge could not be determined. Similarly, publication bias and heterogeneity for most analyses could not be ascertained. We found no concrete evidence of association between the modifiable determinants and self-report PAB/SB in any settings. This is presumably due to intervention ineffectiveness. Design of future interventions should consider to follow the systems-based approach and identify determinants unique to the context of a setting, including policy and environmental determinants.

Applying Community-based System Dynamics to promote child health equity: the case of healthy and fit kids in Milwaukee, WI

Background

Child health equity is influenced by complex systemic factors, including structural racism, socioeconomic disparities, and access to resources. Traditional public health interventions often target individual behaviors, but there is a growing need for systems approaches that address these root causes. This study examines coalition members' perspectives on promoting child health equity in Milwaukee as a result of participating in an intervention that includes Community-based System Dynamics (CBSD).

Methods

In this case study, we used a mixed-methods approach to describe 10 coalition members' perspective shifts over 6 months, after participating in CBSD activities. These activities generated a causal-loop diagram to map the systemic factors influencing child health. Data collection included pre-post interviews and surveys. The data analysis involved thematic analysis of the qualitative data from interviews, which was then integrated with the open-ended survey responses. The themes identified were cross-referenced with the causal-loop diagram factors to validate and refine the understanding of systemic influences on child health.

Results

Post-intervention, coalition members shifted their focus from individual health behaviors to systemic drivers, particularly structural racism and socioeconomic disparities. The causal-loop diagram helped identify leverage points and fostered a readiness for local collective action and policy advocacy.

Conclusion

Integrating CBSD into public health coalitions can shift focus from individual behaviors to systemic causes, enabling more effective interventions. This approach offers valuable insights for promoting child health equity through holistic, community-driven strategies and public policy reforms.

Complexity data science: A spin-off from digital twins

Digital twins offer a new and exciting framework that has recently attracted significant interest in fields such as oncology, immunology, and cardiology. The basic idea of a digital twin is to combine simulation and learning to create a virtual model of a physical object. In this paper, we explore how the concept of digital twins can be generalized into a broader, overarching field. From a theoretical standpoint, this generalization is achieved by recognizing that the duality of a digital twin fundamentally connects complexity science with data science, leading to the emergence of complexity data science as a synthesis of the two. We examine the broader implications of this field, including its historical roots, challenges, and opportunities.

Forces at play: A qualitative study of risk aversion, policy and decision making for children's physically active play in schools

This study investigated (i) the social and political factors driving risk averse decision making for children's physically active play in schools, and (ii) the policies shaping these decisions in Victoria, Australia. A theory-informed multi-method case study design combined policy document mapping, semi-structured interviews, and photo elicitation with 30 education policy actors. Data were analysed using reflexive thematic analysis. Findings showed the policy landscape was heavily skewed towards managing risk and safety (84%; n = 42), with fewer, mostly optional, policies for promoting physical activity, and a lack of policy to promote or protect play. Thematic findings indicated an intersecting range of factors in this setting (including occupational health and safety, knowledge and skill gaps, parent factors, children's physical capabilities, an undervaluing of play) can deter schools from providing an environment that enables children's freely chosen, physically active play. Multi-faceted, systems-based approaches that go beyond interventions aimed at individual behaviour change are needed.