Evaluating recruitment strategies for AUSPICE, a large Australian community-based randomised controlled trial

Barriers and facilitators for recruiting and retaining male participants into longitudinal health research: a systematic review

BACKGROUND

Successfully recruiting male participants to complete a healthcare related study is important for healthcare study completion and to advance our clinical knowledgebase. To date, most research studies have examined the barriers and facilitators of female participants in longitudinal healthcare-related studies with limited information available about the needs of males in longitudinal research. This systematic review examines the unique barriers and facilitators to male recruitment across longitudinal healthcare-related research studies.

METHODS

Following PRIMSA guidelines, MEDLINE, Embase, CINAHL and Web of Science databases were systematically searched using the terms recruitment and/or retention, facilitators and/or barriers and longitudinal studies from 1900 to 2023 which contained separate data on males aged 17-59 years. Health studies or interventions were defined longitudinal if they were greater than or equal to 12 weeks in duration with 3 separate data collection visits.

RESULTS

Twenty-four articles published from 1976-2023 met the criteria. One-third of the studies had a predominantly male sample and four studies recruited only male participants. Males appear disinterested towards participation in health research, however this lack of enthusiasm can be overcome by clear, non-directive communication, and studies that support the participants interests. Facilitating factors are diverse and may require substantial time from research teams.

CONCLUSIONS

Future research should focus on the specific impact of these factors across the spectrum of longitudinal health-related studies. Based on the findings of this systematic review, researchers from longitudinal health-related clinical trials are encouraged to consider male-specific recruitment strategies to ensure successful recruitment and retention in their studies.

REGISTRATION

This systemic review is registered with the PROSPERO database (CRD42021254696).

Persistence of Detectable Anti-Pneumococcal Antibodies 4 Years After Pneumococcal Polysaccharide Vaccination in a Randomised Controlled Trial: The Australian Study for the Prevention through Immunisation of Cardiovascular Events (AUSPICE)

AIM

Mouse models have indicated that the pneumococcal polysaccharide vaccine (PPV) can reduce atherosclerosis. This is probably through a process of molecular mimicry, where phosphorylcholine in the capsular polysaccharide of the vaccine elicits antibodies that cross-react with oxidised low-density lipoprotein and reduce plaque. We investigated whether a similar mechanism occurs in humans.

METHODS

A large national blinded, randomised, placebo-controlled trial of the PPV (Australian Study for the Prevention through Immunisation of Cardiovascular Events [AUSPICE]) is underway with fatal and nonfatal cardiovascular disease (CVD) events as the primary outcome. Participants at one centre agreed to a substudy measuring a number of biomarkers and surrogates of CVD over 4 years, including anti-pneumococcal antibodies (immunoglobulin G and immunoglobulin M), C-reactive protein, carotid intima-media thickness, pulse wave velocity, insulin, fasting blood glucose, glycated haemoglobin, and hepatorenal index.

RESULTS

Antipneumococcal immunoglobulin G and immunoglobulin M were both present and statistically significantly increased in the treated group compared to control at 4 years. However, there were no differences in any of the surrogate measures of CVD or metabolic markers at 4 years.

CONCLUSIONS

While there were prolonged differences in anti-pneumococcal antibody titres following PPV vaccination, these did not appear to provide any cardioprotective effect, as measured by a range of markers. Final results using the fatal and nonfatal CVD events await the completion of national health record linkage next year.

TRIAL REGISTRATION

ACTRN12615000536561.

Factors Associated with Participation in a Multidomain Web-Based Dementia Prevention Trial: Evidence from Maintain Your Brain (MYB)

BACKGROUND

The Maintain Your Brain (MYB) trial aims to prevent cognitive decline and dementia through multidomain, web-based risk-reduction. To facilitate translation, it is important to understand drivers of participation.

OBJECTIVE

To describe characteristics associated with participation in MYB.

METHODS

This was an observational ancillary study of MYB, a randomized controlled trial nested within the 45 and Up Study in New South Wales, Australia. We linked 45 and Up Study survey and MYB participation data. The study cohort comprised 45 and Up Study participants, aged 55-77 years at 1 January 2018, who were invited to participate in MYB. 45 and Up Study participant characteristics and subsequent MYB consent and participation were examined.

RESULTS

Of 98,836 invited, 13,882 (14%) consented to participate and 6,190 participated (6%). Adjusting for age and sex, a wide range of factors were related to participation. Higher educational attainment had the strongest relationship with increased MYB participation (university versus school non-completion; AdjOR = 5.15; 95% CI:4.70-5.64) and lower self-rated quality of life with reduced participation (Poor versus Excellent: AdjOR = 0.19; 95% CI:0.11-0.32). A family history of Alzheimer's disease was related to increased participation but most other dementia risk factors such as diabetes, obesity, stroke, high blood pressure, and current smoking were associated with reduced participation.

CONCLUSION

Higher socio-economic status, particularly educational attainment, is strongly associated with engagement in online dementia prevention research. Increasing population awareness of dementia risk factors, and better understanding the participation barriers in at-risk groups, is necessary to ensure online interventions are optimally designed to promote maximum participation.

The Use of Adaptive Sampling to Reach Disadvantaged Populations for Immunization Programs and Assessments: A Systematic Review

Vaccines prevent 4-5 million deaths every year, but inequities in vaccine coverage persist among key disadvantaged subpopulations. Under-immunized subpopulations (e.g., migrants, slum residents) may be consistently missed with conventional methods for estimating immunization coverage and assessing vaccination barriers. Adaptive sampling, such as respondent-driven sampling, may offer useful strategies for identifying and collecting data from these subpopulations that are often "hidden" or hard-to-reach. However, use of these adaptive sampling approaches in the field of global immunization has not been systematically documented. We searched PubMed, Scopus, and Embase databases to identify eligible studies published through November 2020 that used an adaptive sampling method to collect immunization-related data. From the eligible studies, we extracted relevant data on their objectives, setting and target population, and sampling methods. We categorized sampling methods and assessed their frequencies. Twenty-three studies met the inclusion criteria out of the 3069 articles screened for eligibility. Peer-driven sampling was the most frequently used adaptive sampling method (57%), followed by geospatial sampling (30%), venue-based sampling (17%), ethnographic mapping (9%), and compact segment sampling (9%). Sixty-one percent of studies were conducted in upper-middle-income or high-income countries. Data on immunization uptake were collected in 65% of studies, and data on knowledge and attitudes about immunizations were collected in 57% of studies. We found limited use of adaptive sampling methods in measuring immunization coverage and understanding determinants of vaccination uptake. The current under-utilization of adaptive sampling approaches leaves much room for improvement in how immunization programs calibrate their strategies to reach "hidden" subpopulations.

Reliability, Validity, and User-Experience of Remote Unsupervised Computerized Neuropsychological Assessments in Community-Living 55- to 75-Year-Olds

BACKGROUND

Self-administered computerized neuropsychological assessments (CNAs) provide lower cost, more accessible alternatives to traditional in-person assessments but lack critical information on psychometrics and subjective experience of older adults in remote testing environments.

OBJECTIVE

We used an online brief battery of computerized tasks selected from the Cogstate Brief Battery (CBB) and Cambridge Brain Sciences (CBS) to 1) determine test-retest reliability in an unsupervised setting; 2) examine convergent validity with a comprehensive 'gold standard' paper-and-pencil neuropsychological test battery administered in-person; and 3) explore user-experience of remote computerized testing and individual tests.

METHODS

Fifty-two participants (mean age 65.8±5.7 years) completed CBB and CBS tests on their own computer, unsupervised from home, on three occasions, and visited a research center for an in-person paper-and-pencil assessment. They also completed a user-experience questionnaire.

RESULTS

Test-retest reliabilities varied for individual measures (ICCs = 0.20 to 0.83). Global cognition composites showed excellent reliability (ICCs > 0.8 over 1-month follow-up). A strong relationship between a combination of CNA measures and paper-and-pencil battery was found (canonical correlation R = 0.87, p = 0.04). Most tests were rated as enjoyable with easy-to-understand instructions. Ratings of general experience with online testing were mostly favorable; few had difficulty concentrating (17%) or using the computer for tasks (10%), although over one-third experienced performance anxiety (38%).

CONCLUSION

A combined brief online battery selected from two CNAs demonstrated robust psychometric standards for reliability (global composite), and convergent validity with a gold standard battery, and mostly good usability and acceptability in the remote testing environment.

Generation of cardio-protective antibodies after pneumococcal polysaccharide vaccine: Early results from a randomised controlled trial

BACKGROUND AND AIMS

Observational studies have demonstrated that the pneumococcal polysaccharide vaccine (PPV) is associated with reduced risk of cardiovascular events. This may be mediated through IgM antibodies to OxLDL, which have previously been associated with cardioprotective effects. The Australian Study for the Prevention through Immunisation of Cardiovascular Events (AUSPICE) is a double-blind, randomised controlled trial (RCT) of PPV in preventing ischaemic events. Participants received PPV or placebo once at baseline and are being followed-up for incident fatal and non-fatal myocardial infarction or stroke over 6 years.

METHODS

A subgroup of participants at one centre (Canberra; n = 1,001) were evaluated at 1 month and 2 years post immunisation for changes in surrogate markers of atherosclerosis, as pre-specified secondary outcomes: high-sensitive C-reactive protein (CRP), pulse wave velocity (PWV), and carotid intima-media thickness (CIMT). In addition, 100 participants were randomly selected in each of the intervention and control groups for measurement of anti-pneumococcal antibodies (IgG, IgG2, IgM) as well as anti-OxLDL antibodies (IgG and IgM to CuOxLDL, MDA-LDL, and PC-KLH).

RESULTS

Concentrations of anti-pneumococcal IgG and IgG2 increased and remained high at 2 years in the PPV group compared to the placebo group, while IgM increased and then declined, but remained detectable, at 2 years. There were statistically significant increases in all anti-OxLDL IgM antibodies at 1 month, which were no longer detectable at 2 years; there was no increase in anti-OxLDL IgG antibodies. There were no significant changes in CRP, PWV or CIMT between the treatment groups at the 2-year follow-up.

CONCLUSIONS

PPV engenders a long-lasting increase in anti-pneumococcal IgG, and to a lesser extent, IgM titres, as well as a transient increase in anti-OxLDL IgM antibodies. However, there were no detectable changes in surrogate markers of atherosclerosis at the 2-year follow-up. Long-term, prospective follow-up of clinical outcomes is continuing to assess if PPV reduces CVD events.

Impact of personal genomic risk information on melanoma prevention behaviors and psychological outcomes: a randomized controlled trial

Purpose

We evaluated the impact of personal melanoma genomic risk information on sun-related behaviors and psychological outcomes.

Methods

In this parallel group, open, randomized controlled trial, 1,025 Australians of European ancestry without melanoma and aged 18–69 years were recruited via the Medicare database (3% consent). Participants were randomized to the intervention (n = 513; saliva sample for genetic testing, personalized melanoma risk booklet based on a 40-variant polygenic risk score, telephone-based genetic counseling, educational booklet) or control (n = 512; educational booklet). Wrist-worn ultraviolet (UV) radiation dosimeters (10-day wear) and questionnaires were administered at baseline, 1 month postintervention, and 12 months postbaseline.

Results

At 12 months, 948 (92%) participants completed dosimetry and 973 (95%) the questionnaire. For the primary outcome, there was no effect of the genomic risk intervention on objectively measured UV exposure at 12 months, irrespective of traditional risk factors. For secondary outcomes at 12 months, the intervention reduced sunburns (risk ratio: 0.72, 95% confidence interval: 0.54–0.96), and increased skin examinations among women. Melanoma-related worry was reduced. There was no overall impact on general psychological distress.

Conclusion

Personalized genomic risk information did not influence sun exposure patterns but did improve some skin cancer prevention and early detection behaviors, suggesting it may be useful for precision prevention. There was no evidence of psychological harm.

Conducting Population Health Research during the COVID-19 Pandemic: Impacts and Recommendations

The COVID-19 pandemic has resulted in many changes, including restrictions on indoor gatherings and visitation to residential aged care facilities, hospitals and certain communities. Coupled with potential restrictions imposed by health services and academic institutions, these changes may significantly impact the conduct of population health research. However, the continuance of population health research is beneficial for the provision of health services and sometimes imperative. This paper discusses the impact of COVID-19 restrictions on the conduct of population health research. This discussion unveils important ethical considerations, as well as potential impacts on recruitment methods, face-to-face data collection, data quality and validity. In addition, this paper explores potential recruitment and data collection methods that could replace face-to-face methods. The discussion is accompanied by reflections on the challenges experienced by the authors in their own research at an oral health service during the COVID-19 pandemic and alternative methods that were utilised in place of face-to-face methods. This paper concludes that, although COVID-19 presents challenges to the conduct of population health research, there is a range of alternative methods to face-to-face recruitment and data collection. These alternative methods should be considered in light of project aims to ensure data quality is not compromised.

Pneumococcal polysaccharide vaccine is a cost saving strategy for prevention of acute coronary syndrome

OBJECTIVE

There is evidence that the pneumococcal polysaccharide vaccine (PPV) may reduce cardiovascular disease. We aimed to evaluate the cost-effectiveness of PPV for primary prevention of acute coronary syndrome (ACS) in the elderly in Australia.

METHODS

A Markov model was developed to investigate the costs, QALYs and ICERs of PPV administration in those aged ≥65 years without a history of ACS from the perspective of Australian healthcare system, using elderly-specific clinical data and local costs from Australian Heart Foundation and Australian Institute of Health and Welfare databases. A ten-years horizon was used, and all costs and health outcomes were discounted at 5% annually. The impact of various assumptions was tested with sensitivity analyses.

RESULTS

In the base-case analysis, interventional strategy (100% PPV coverage) prevented an additional five incident ACS events among 1000 "healthy" elderly individuals compared with standard of care (50% PPV coverage) over 10 years. 100% PPV was the dominant strategy, resulting in a QALY gain of 0.0075 and cost saving of AU$ 179 per person. The results were most sensitive to effectiveness of PPV at preventing ACS and reducing hospital bed-days, and cost of ACS admission, but in all sensitivity analyses 100% PPV remained the dominant strategy. Shortening the time horizon from ten to five years resulted in further cost saving.

CONCLUSION

PPV for the prevention of ACS in those aged ≥65 is a dominant intervention strategy, with cost saving and minor improvements in QALY. Healthcare providers should promote PPV administration for all eligible populations.