The progressive place paradox: Status-based health inequalities are magnified in more economically progressive Swiss localities

Low socioeconomic status (measured both objectively and subjectively) is systematically associated with worse health. Amid renewed interest in contextual influences on health inequalities, we ask whether variation in the prevailing ideological climate moderates the size of the health gap between low and high status individuals. Based on the minority stress hypothesis, we expect that living in an economically progressive place within Switzerland - places where more residents endorse the need for change to the economic status quo - will reduce the magnitude of the health gap. Multilevel modelling of MOSAiCH 2015-2020 data shows the opposite: low status individuals in progressive places report markedly lower subjective health and life satisfaction than similarly low status individuals in conservative places, such that status-based health inequalities are maximised in progressive places. We interpret this apparent progressive place paradox in terms of collective inefficacy and system frustration, which we argue is the corollary of system justification.

Effect of area-level socioeconomic deprivation on mental and physical health: A longitudinal natural experiment among refugees in Germany

Existing studies on contextual health effects struggle to account for compositional bias, limiting causal interpretation. We use refugee dispersal in Germany as a natural experiment to study the effect of area-level socioeconomic deprivation on mental and physical health, while considering the potential mediating role of neighbourhood characteristics. Refugees subject to dispersal (n = 1466) are selected from a nation-wide longitudinal refugee study (IAB-SOEP-BAMF Panel; 2016-2018). Multi-level linear regression models, adjusted for age, sex, education, country of origin, federal state, asylum status and length of residence in Germany, are fitted to the change in mental and physical health subscales of the SF-12 depending on quintiles (Q1 - Q5) of commune-level socioeconomic deprivation (German Index of Socioeconomic Deprivation, GISD). This is followed by sensitivity analyses and mediation analyses for housing, social cohesion, proportion of non-citizens in the neighbourhood, access to green space, population density and primary care physician density. Residency in districts with moderate-high deprivation (Q4) has a negative impact on physical health (coef.: -2.2, 95%CI: -4.1;-0.2) compared to lowest deprivation (Q1). Moderate-high deprivation (Q4) has a positive impact on mental health, but the effect is statistically insignificant (coef.: 1.6, 95%CI: -0.7; 3.9). Comparisons with other deprivation quintiles are statistically insignificant. Sensitivity analyses confirm results of the final models, while no mediating factors show a substantial impact on the observed relationship. The results point to gaps in health and social service provision for refugees living in the most deprived regions, but further research is required to understand the precise mechanisms behind the observed relationships. Further research using longer timeframes and larger sample sizes are required to confirm results.

Contextual effects: how to, and how not to, quantify them

The importance of contextual effects and their roles in clinical care controversial. A Cochrane review published in 2010 concluded that placebo interventions lack important clinical effects overall, but that placebo interventions can influence patient-reported outcomes such as pain and nausea. However, systematic reviews published after 2010 estimated greater contextual effects than the Cochrane review, which stems from the inappropriate methods employed to quantify contextual effects. The effects of medical interventions (i.e., the total treatment effect) can be divided into three components: specific, contextual, and non-specific. We propose that the most effective method for quantifying the magnitude of contextual effects is to calculate the difference in outcome measures between a group treated with placebo and a non-treated control group. Here, we show that other methods, such as solely using the placebo control arm or calculation of a 'proportional contextual effect,' are limited and should not be applied. The aim of this study is to provide clear guidance on best practices for estimating contextual effects in clinical research.

Refinement of face representations by exposure reveals different time scales of biases in face processing

Experience modulates face processing abilities so that face discrimination and recognition improve with development, especially for more frequently experienced faces (e.g., own-race faces). Although advanced models describe how experience generally modulates perception, the mechanism by which exposure refines internal perceptual representations of faces is unknown. To address this issue, we investigated the effect of short- and long-term experienced stimulus history on face processing. Participants performed same-different judgments in a serial discrimination task where two consecutive faces were drawn from a distribution of morphed faces. Use of stimulus statistics was measured by testing the gravitation of face representations towards the mean of a range of morphed faces around which they were sampled (regression-to-the-mean). The results demonstrated regression of face representations towards the experienced mean and the retention of stimulus statistics over days. In trials where regression facilitated discrimination, the bias diminished the otherwise disadvantage of other-race over own-races faces. The dynamics of the perceptual bias, probed by trial-by-trial performance, further indicated different timescales of the bias, depending on perceptual expertise: people with weak face-recognition skills showed the use of a stable reference, built on long-term statistics accumulated over many trials, along with an updating of this reference by recent trials. In contrast, the strong face recognizers showed a different pattern where sequential effects mostly contributed to discrimination, with relatively minimal reliance on the long-term average for other-race faces. The findings suggest a mechanism by which exposure refines face representations and reveal, for the first time in adults, associations between levels of specialization of perceptual representations and the extent to which these representations become narrowly tuned.

Disaggregating level-specific effects in cross-classified multilevel models

In psychology and other fields, data often have a cross-classified structure, whereby observations are nested within multiple types of non-hierarchical clusters (e.g., repeated measures cross-classified by persons and stimuli). This paper discusses ways that, in cross-classified multilevel models, slopes of lower-level predictors can implicitly reflect an ambiguous blend of multiple effects (for instance, a purely observation-level effect as well as a unique between-cluster effect for each type of cluster). The possibility of conflating multiple effects of lower-level predictors is well recognized for non-cross-classified multilevel models, but has not been fully discussed or clarified for cross-classified contexts. Consequently, in published cross-classified modeling applications, this possibility is almost always ignored, and researchers routinely specify models that conflate multiple effects. In this paper, we show why this common practice can be problematic, and show how to disaggregate level-specific effects in cross-classified models. We provide a novel suite of options that include fully cluster-mean-centered, partially cluster-mean-centered, and contextual effect models, each of which provides a unique interpretation of model parameters. We further clarify how to avoid both fixed and random conflation, the latter of which is widely misunderstood even in non-cross-classified models. We provide simulation results showing the possible deleterious impact of such conflation in cross-classified models, and walk through pedagogical examples to illustrate the disaggregation of level-specific effects. We conclude by considering additional model complexities that can arise with cross-classification, providing guidance for researchers in choosing among model specifications, and describing newly available software to aid researchers who wish to disaggregate effects in practice.

Context, health and migration: a systematic review of natural experiments

Background

Migration health research pays little attention to the places into which people migrate. Studies on health effects of contextual factors are often limited because of the ability of individuals to self-select their environment, but natural experiments may allow for the causal effect of contexts to be examined. The objective was to synthesise the evidence on contextual health effects from natural experiments among migrant groups.

Methods

We performed a systematic review of natural experiments among migrant populations in PubMed/MEDLINE, The Cochrane Library, Web of Science, CINAHL and Google Scholar for literature published until 13 October 2022. 5870 articles were screened in duplicate using the following inclusion criteria: quantitative natural experiment design, migrant population, context factor as treatment variable and health or healthcare outcome variable. Synthesis without meta-analysis was performed following quality appraisal using the EPHPP tool for quantitative studies and data extraction (PROSPERO: CRD42020169236).

Findings

The 46 included articles provide evidence for negative effects of neighbourhood disadvantage on physical health and mortality, while finding mixed effects on mental health. Articles comparing migrants with those that stayed behind demonstrate detrimental effects of migration and adverse post-migratory contexts on physical health and mortality, while demonstrating favourable effects for mental and child health. Natural experiments of policy environments indicate the negative impacts of restrictive migration and social policies on healthcare utilization, mental health and mortality, as well as the positive health effects when restrictions are lifted.

Interpretation

Natural experiments complement observational studies and provide robust evidence to advocate for more inclusive migration, health and social policies as well as neighbourhood improvement programmes. In order to strengthen the methodological approach, future research utilising natural experiments should be more explicit in the mechanisms underlying the experiment and provide details on potential causal mechanisms for the observed effects.

Funding

German Science Foundation (FOR: 2928/GZ: BO5233/1-1).

A by-product of big government: the attenuating role of public procurement for the effectiveness of grants-based entrepreneurship policy

We study the contextual role of public procurement for the effectiveness of grants-based entrepreneurship policy. Drawing on the resource-based view of the firm, we argue that partaking in procurement can erode grant effectiveness by relaxing a firm's preexisting financial constraints and diverting managerial attention away from market-centered resource configurations. To test our hypothesis, we use detailed firm-level data from Slovenia and combine matching with difference-in-differences. When firms are not involved in procurement, all investigated types of grants meet the intended policy goals, apart from productivity growth. In contrast, when firms participate in procurement, small-business grants exhibit generally weaker effects, R&D grants fail to have any impact, and employment grants lastingly reduce firm productivity. Given that public procurement occupies a large footprint in many economies, our analysis highlights an unintended adverse by-product of big government and underscores the limits of state capitalism.

Supplementary Information

The online version contains supplementary material available at 10.1007/s11187-023-00788-w.

The impact of county-level fees & fines as exploitative revenue generation on US birth outcomes 2011-2015

Fees and fines collected through courts and law enforcement can comprise a considerable proportion of revenue for local governments. Law enforcement, as agents of revenue generation, change policing behavior to increase revenue, at times targeting Black and brown neighborhoods to bolster municipal budgets. This structural racism in revenue generation has not yet been assessed as an exposure for adverse health. Using the 2012 Census of Governments, and 2011-2015 vital statistics from the National Center of Health Statistics, we examine the relationship between countyaverage fees and fines as a percent of total own-source revenue and county-level characteristics, and risk of preterm birth and low birthweight across the United States. Mothers residing in counties with the greatest reliance on fees and fines had 1.08 (95% CI: 1.03-1.12) times the odds of preterm birth and 1.07 (95% CI: 1.02-1.11) times the odds of low birthweight than mothers residing in counties with the least reliance on fees and fines, controlling for individual- and county-level covariates. The addition of countylevel racial composition, and the Index of Concentration at the Extremes (ICE), reduced these associations yet remained statistically significant. Future studies should continue to examine how racist, exploitative revenue generation through police and court activities influences the health of residents.

Contextual and own-age effects in age perception

Our judgement of certain facial characteristics such as emotion, attractiveness or age, is affected by context. Faces that are flanked by younger faces, for example, are perceived as being younger, whereas faces flanked by older faces are perceived as being older. Here, we investigated whether contextual effects in age perception are moderated by own age effects. On each trial, a target face was presented on the screen, which was flanked by two faces. Flanker faces were either identical to the target face, were 10 years younger or 10 years older than the target face. We asked 40 older (64–69 years) and 43 younger adults (24–29) to estimate the age of the target face. Our results replicated previous studies and showed that context affects age estimation of faces flanked by target faces of different ages. These context effects were more pronounced for younger compared to older flankers but present across both tested age groups. An own-age advantage was observed for older adults for unflanked faces who had larger estimation errors for younger faces compared to older faces and younger adults. Flanker effects, however, were not moderated by own-age effects. It is likely that the increased effect of younger flankers is due to mechanisms related to perceptual averaging.

Can Crossover and Altered Magnitude Estimation in Neglect Be Explained by Contextual Effects?

Three studies that used experimental manipulations of stimulus context and correlational analyses were conducted to examine how contextual effects influence magnitude estimation and the crossover effect on line bisection. Previous work had shown that although orienting attention to one end of a line prior to bisection determines the direction in which crossover occurs, bias in magnitude estimation actually produces the crossover effect. The influence of contextual effects on magnitude estimation, however, was not examined in these previous models of crossover. Consequently, the purpose of the present investigation was to examine these effects. Subjects in the current studies were healthy controls and people who had right and left hemisphere injury due to stroke, both with and without spatial neglect. Study 1 examined the crossover effect for lines bisected with and without a stimulus context. Study 2 examined both stimulus order as well as response order context effects on magnitude estimation. Study 3 examined how much variance in magnitude estimation was accounted for by stimulus contextual effects and how stimulus context influenced the crossover effect. The results showed that contextual bias was ubiquitous but relatively small in the magnitude estimates of normal subjects. Contextual bias was exaggerated to a similar degree in subjects with right or left hemisphere injury due to stroke, but the amount of variance accounted by contextual bias was still quite small. A novel finding of study 2 was that contextual effects can be induced by previous responses to stimuli as well as by the magnitude of preceding stimuli in subjects with unilateral brain injury. This may be a contextual effect related to response perseveration. Finally, studies 1 and 3 indicated that contextual effects strengthened the crossover effect on line bisection, primarily on relatively short lines. Contextual effects, however, cannot fully account for the crossover effect, because crossover bisections were observed also in the absence of a stimulus context. It is concluded that the crossover effect is explained by biases in attentional orientation and magnitude estimation. Contextual effects represent one source of bias in magnitude estimation that influences the crossover effect by promoting contralateral errors on short line lengths (<2 cm).

Placebo response and effect in randomized clinical trials: meta-research with focus on contextual effects

BACKGROUND

Contextual effects (i.e., placebo response) refer to all health changes resulting from administering an apparently inactive treatment. In a randomized clinical trial (RCT), the overall treatment effect (i.e., the post-treatment effect in the intervention group) can be regarded as the true effect of the intervention plus the impact of contextual effects. This meta-research was conducted to examine the average proportion of the overall treatment effect attributable to contextual effects in RCTs across clinical conditions and treatments and explore whether it varies with trial contextual factors.

METHODS

Data was extracted from trials included in the main meta-analysis from the latest update of the Cochrane review on "Placebo interventions for all clinical conditions" (searched from 1966 to March 2008). Only RCTs reported in English having an experimental intervention group, a placebo comparator group, and a no-treatment control group were eligible.

RESULTS

In total, 186 trials (16,655 patients) were included. On average, 54% (0.54, 95%CI 0.46 to 0.64) of the overall treatment effect was attributable to contextual effects. The contextual effects were higher for trials with blinded outcome assessor and concealed allocation. The contextual effects appeared to increase proportional to the placebo effect, lower mean age, and proportion of females.

CONCLUSION

Approximately half of the overall treatment effect in RCTs seems attributable to contextual effects rather than to the specific effect of treatments. As the study did not include all important contextual factors (e.g., patient-provider interaction), the true proportion of contextual effects could differ from the study's results. However, contextual effects should be considered when assessing treatment effects in clinical practice.

TRIAL REGISTRATION

PROSPERO CRD42019130257 . Registered on April 19, 2019.

The effect of contextual information on professional judgment: Reliability and biasability of expert workplace safety inspectors

INTRODUCTION

A critical aspect of occupational safety is workplace inspections by experts, in which hazards are identified. Scientific research demonstrates that expectation generated by context (i.e., prior knowledge and experience) can bias the judgments of professionals and that individuals are largely unaware when their judgments are affected by bias.

METHOD

The current research tested the reliability and biasability of expert safety inspectors' judgments. We used a two-study design (Study 1, N = 83; Study 2, N = 70) to explore the potential of contextual, task-irrelevant, information to bias professionals' judgments. We examined three main issues: (1) the effect that biasing background information (safe and unsafe company history) had on professional regulatory safety inspectors' judgments of a worksite; (2) the reliability of those judgments amongst safety inspectors and (3) inspectors' awareness of bias in their judgments and confidence in their performance.

RESULTS

Our findings establish that: (i) inspectors' judgments were biased by historical contextual information, (ii) they were not only biased, but the impact was implicit: they reported being unaware that it affected their judgments, and (iii) independent of our manipulations, inspectors were inconsistent with one another and the variations were not a product of experience.

CONCLUSION

Our results are a replication of findings from a host of other professional domains, where honest, hardworking professionals underappreciate the biasing effect of context on their decision making. The current paper situates these findings within the relevant research on safety inspection, cognitive bias and decision making, as well as provides suggestions for bias mitigation in workplace safety inspection. Practical Application: Our results have implications for occupational health and safety given that inspection is an integral aspect of an effective safety system. In addition to our findings, this study contributes to the literature by providing recommendations regarding how to mitigate the effect of bias in inspection.

Cross-classified multilevel models (CCMM) in health research: A systematic review of published empirical studies and recommendations for best practices

Recognizing that health outcomes are influenced by and occur within multiple social and physical contexts, researchers have used multilevel modeling techniques for decades to analyze hierarchical or nested data. Cross-Classified Multilevel Models (CCMM) are a statistical technique proposed in the 1990s that extend standard multilevel modeling and enable the simultaneous analysis of non-nested multilevel data. Though use of CCMM in empirical health studies has become increasingly popular, there has not yet been a review summarizing how CCMM are used in the health literature. To address this gap, we performed a scoping review of empirical health studies using CCMM to: (a) evaluate the extent to which this statistical approach has been adopted; (b) assess the rationale and procedures for using CCMM; and (c) provide concrete recommendations for the future use of CCMM. We identified 118 CCMM papers published in English-language literature between 1994 and 2018. Our results reveal a steady growth in empirical health studies using CCMM to address a wide variety of health outcomes in clustered non-hierarchical data. Health researchers use CCMM primarily for five reasons: (1) to statistically account for non-independence in clustered data structures; out of substantive interest in the variance explained by (2) concurrent contexts, (3) contexts over time, and (4) age-period-cohort effects; and (5) to apply CCMM alongside other techniques within a joint model. We conclude by proposing a set of recommendations for use of CCMM with the aim of improved clarity and standardization of reporting in future research using this statistical approach.

Can we recognize people based on their body-alone? The roles of body motion and whole person context

While most studies on person recognition examine the face alone, recent studies have shown evidence for the contribution of the body and gait to person recognition beyond the face. Nevertheless, little is known on whether person recognition can be performed based on the body alone. In this study, we examined two sources of information that may enhance body-based person recognition: body motion and whole person context. Body motion has been shown to contribute to person recognition especially when facial information is unclear. Additionally, generating whole person context, by attaching faceless heads to bodies, has been shown to activate face processing mechanisms and may therefore enhance body-based person recognition. To assess body-based person recognition, participants performed a sequential matching task in which they studied a video of a person walking followed by a headless image of the same or different identity. The role of body motion was examined by comparing recognition from dynamic vs. static headless bodies. The role of whole person context was examined by comparing bodies with and without faceless heads. Our findings show that person recognition from the body alone was better in dynamic vs. static displays indicating that body motion contributed to body-based person recognition. In addition, whole person context contributed to body-based person recognition when recognition was performed in static displays. Overall these findings show that recognizing people based on their body alone is challenging but can be performed under certain circumstances that enhance the processing of the body when seeing the whole dynamic person.

Contextual effects of social integration and disintegration on health status: evidence from South Korea

BACKGROUND

Many studies have shown that various social integration variables represented by social capital are beneficial to communities, including collective health. However, the rapid decline in fertility rates and the breakup of familyism in developed countries require a new approach to social disintegration, but the literature is insufficient. Here, we explored the contextual effects of social integration and social disintegration on the health of individuals.

METHODS

The research data consist of merged datasets of 6909 respondents who were quota-sampled by approximately 30 people from 229 local governments in Korea. The individual-level independent variable is a social integration measure consisting of 26 questions in four areas. The community-level independent variables are five integral and aggregate variables extracted from 81 indicators. The dependent variable is self-rated health status. Potential confounders are gender, age, annual income, educational attainment, district type, and the number of beds in medical institutions per 1000 people.

RESULTS

The results showed that at the individual level, the higher the inclusive attitude of in- and out-of-networks, after adjusting for potential confounders, the less likely the respondent belongs to the unhealthy group (p < 0.001). At the community level, the higher the proportion of single-person households in a community after adjusting for potential confounders, the less likely the respondent belongs to the unhealthy group (p < 0.05). The effect size was 0.22.

CONCLUSION

Thus far, social integration has been preferred, with the positive aspects of social capital being emphasized. However, this study shows that in some cases, social disintegration can instead positively influence an individual's health. Therefore, further studies of the various conditions of social context effects on health are necessary.

A tale half told: State exclusionary and inclusionary regimes, incarceration of fathers, and the educational attainment of children

Paternal incarceration leads to educational disparities among children who are innocent of their fathers' crimes. The scale and concentration of mass paternal incarceration thus harms millions of innocent American children. Current individuallevel analyses neglect the contribution of macro-level variation in responses of punitive state regimes to this social problem. We hypothesize that state as well as individual level investment in exclusionary paternal incarceration diminishes the educational attainment of children, although state inclusionary investment in welfare and education can offset some - and could potentially offset more - of this harm. Understanding intergenerational educational attainment therefore requires individual- and contextuallevel analyses. We use Hierarchical Generalized Linear Models to analyze the National Longitudinal Survey of Adolescent to Adult Health. Disparities in postsecondary educational outcomes are especially detrimental for children of incarcerated fathers located in state regimes with high levels of paternal incarceration and concentrated disadvantage. This has important implications for intergenerational occupational and status attainment.

County-level jail incarceration and preterm birth among non-Hispanic Black and white U.S. women, 1999-2015

Jail incarceration is widely prevalent in the United States, with disproportionate impacts on communities of color, yet little research has quantified its health consequences for communities. We assess county-level jail incarceration as a contextual stressor for individual-level preterm birth among non-Hispanic Black and White U.S. women, the vast majority (>99%) of whom were not incarcerated, between 1999 and 2015. We linked county jail incarceration rates to birth certificate data for all births to resident non-Hispanic Black and White U.S. women (N = 41, 911, 094). Using multilevel logistic regression models, we estimated the association between quintiles of county jail incarceration rates and the odds of preterm birth, adjusting for maternal- and county-level covariates and state fixed effects. Women living in counties in the highest quintile of jail incarceration rates had 1.08 (95% Confidence Interval (CI): 1.07-1.09) times greater odds of preterm birth, adjusting for covariates, compared to women living in counties with the lowest quintile of jail incarceration rates. Taken together with other research, these findings suggest policies to lower jail incarceration rates could potentially help prevent preterm birth and other adverse population health consequences of mass incarceration.

The effects of suppressing the biological stress systems on social threat-assessment following acute stress

RATIONALE

Stress is associated with increased sensitivity to threat. Previous investigations examining how stress affects threat processing have largely focused on biomarker responses associated with either the sympathetic-nervous-system (SNS) or the hypothalamus-pituitary-adrenal (HPA) axis.

OBJECTIVES

We pharmacologically suppressed activations of SNS, HPA, or both, prior to stress and investigated how each stress system modulates social threat assessment.

METHODS

One hundred sixty-one healthy men and women were randomized in a between-subject design, to one of four pharmacological or placebo conditions: dexamethasone-placebo, placebo-propranolol, dexamethasone-propranolol, or placebo-placebo. Participants provided threat assessments for angry and neutral human faces on a baseline day, and immediately after stress induction on a testing day.

RESULTS

With both systems responding normally to stress (placebo-placebo), threat assessment was higher for neutral faces compared with angry. Compared with placebo, SNS suppression resulted in increased threat assessment for angry faces. HPA suppression resulted in decreased threat assessment for neutral and angry faces. When both systems were suppressed, there was an increase in threat assessment for angry faces, and no difference from placebo for neutral.

CONCLUSION

Our findings demonstrated that when intact, the biological stress systems adaptively support organisms during stress by focusing attention towards specific stimuli that are relevant to the threat. Dysregulations of the stress systems result in important system specific consequences on threat evaluation, such that suppression of either stress system alone resulted in reduced threat assessment for contextually relevant threatening stimuli, whereas when both systems were suppressed, individuals appear indiscriminately attentive to all potential threats in the environment, resulting in increased threat processing of both contextually relevant and irrelevant stimuli. Given that stress-related psychopathologies have been associated with dysregulations of the stress systems and biased responses to social threat, a systematic understanding of the mechanisms that underlie how stress systems modulate social threat assessment is needed, and can provide important insights into the cognitive processes that are involved in the development and maintenance of stress-related psychopathologies.

Adolescent Sexual Initiation: A Cross-Classified Multilevel Analysis of Peer Group-, School-, and Neighborhood-Level Influences

PURPOSE

This study examines the simultaneous roles of neighborhood, school, and peer group contexts on variation in age of U.S. adolescent sexual initiation (coitarche). All three contexts have been shown to be important determinants of adolescent sexual and reproductive health outcomes but are typically examined separately, leaving a large gap in our understanding of their relative and joint importance. Furthermore, little is known about whether these contexts matter differently for boys and girls.

METHODS

Using sociocentric network data from the National Longitudinal Study of Adolescent to Adult Health, we combine gender-stratified analyses, social network community detection (to identify teens' social cliques), and cross-classified multilevel modeling to simultaneously analyze gender, neighborhood, school, and peer group effects. These results are compared against results from traditional multilevel models (MLMs), which analyze the contexts individually.

RESULTS

Evaluated separately in MLM, peer groups accounted for 6.79% of the total variation in coitarche, schools for 3.56%, and neighborhoods for 4.11%. Under simultaneous cross-classified multilevel modeling analysis, a different story emerges: peer groups and schools accounted for 3.66% and 3.19% of the total variation in coitarche, respectively, whereas neighborhood explained only 1.16% of the total variation. Stratified analyses indicate that gender modifies these associations.

CONCLUSIONS

Results demonstrate that omitting any one of these contexts may lead to an overestimation of the importance of contexts included in models. When modeled simultaneously with neighborhoods, our findings suggest that peer groups and schools are meaningful contributing contexts to the variance in sexual initiation, and that these contexts matter differently for boys and girls.

Contextual effects on binocular matching are evident in primary visual cortex

Global context can dramatically influence local visual perception. This phenomenon is well-documented for monocular features, e.g., the Kanizsa triangle. It has been demonstrated for binocular matching: the disambiguation of the Wallpaper Illusion via the luminance of the background. For monocular features, there is evidence that global context can influence neuronal responses as early as V1. However, for binocular matching, the activity in this area of the visual cortex is thought to represent local processing, suggesting that the influence of global context may occur at later stages of cortical processing. Here we sought to test if binocular matching is influenced by contextual effects in V1, using fMRI to measure brain activity while participants viewed perceptually ambiguous “wallpaper” stereograms whose depth was disambiguated by the luminance of the surrounding region. We localized voxels in V1 corresponding to the ambiguous region of the pattern, i.e., where the signal received from the eyes was not predictive of depth, and despite the ambiguity of the input signal, using multi-voxel pattern analysis we were able to reliably decode perceived (near/far) depth from the activity of these voxels. These findings indicate that stereoscopic related neural activity is influenced by global context as early as V1.

Top-down attentional factors modulate action priming in reach-to-grasp action

Previous studies report that viewing exaggerated, high-lifting reaches (versus direct reaches) primes higher vertical deviation in wrist trajectory in the observer's subsequent reaches (trajectory priming), but it is unclear to what extent this effect depends upon task instructions relevant to top-down attention. In two experiments, participants were instructed to gaze at a dot presented on a large monitor for a colour-change go signal that cued them to execute a direct reach to a target. In the background, the monitor also displayed life-sized films of a human model. The films were of the model either remaining still or reaching to grasp a target with either a direct trajectory or an exaggerated, high-lifting trajectory. When the dot traced the human model's wrist throughout her movement, a robust trajectory priming effect emerged. When the dot remained stationary in a central location but the human model reached in the background, the human model's trajectory did not alter the participants' trajectories. Finally, when the dot traced exaggerated and direct trajectories and the human model remained stationary, the dot's movement produced an attenuated, non-significant trajectory priming effect. These findings show that top-down attentional factors modulate trajectory priming. In addition, a moving non-human stimulus does not produce the same degree of action priming when contextual factors make salient its independence of human agency and/or intention.

Does an uneven sample size distribution across settings matter in cross-classified multilevel modeling? Results of a simulation study

BACKGROUND

Recent advances in multilevel modeling allow for modeling non-hierarchical levels (e.g., youth in non-nested schools and neighborhoods) using cross-classified multilevel models (CCMM). Current practice is to cluster samples from one context (e.g., schools) and utilize the observations however they are distributed from the second context (e.g., neighborhoods). However, it is unknown whether an uneven distribution of sample size across these contexts leads to incorrect estimates of random effects in CCMMs.

METHODS

Using the school and neighborhood data structure in Add Health, we examined the effect of neighborhood sample size imbalance on the estimation of variance parameters in models predicting BMI. We differentially assigned students from a given school to neighborhoods within that school's catchment area using three scenarios of (im)balance. 1000 random datasets were simulated for each of five combinations of school- and neighborhood-level variance and imbalance scenarios, for a total of 15,000 simulated data sets. For each simulation, we calculated 95% CIs for the variance parameters to determine whether the true simulated variance fell within the interval.

RESULTS

Across all simulations, the "true" school and neighborhood variance parameters were estimated 93-96% of the time. Only 5% of models failed to capture neighborhood variance; 6% failed to capture school variance.

CONCLUSIONS

These results suggest that there is no systematic bias in the ability of CCMM to capture the true variance parameters regardless of the distribution of students across neighborhoods. Ongoing efforts to use CCMM are warranted and can proceed without concern for the sample imbalance across contexts.

Contextual effects and cancer outcomes in the United States: a systematic review of characteristics in multilevel analyses

PURPOSE

There is increasing call for the utilization of multilevel modeling to explore the relationship between place-based contextual effects and cancer outcomes in the United States. To gain a better understanding of how contextual factors are being considered, we performed a systematic review.

METHODS

We reviewed studies published between January 1, 2002 and December 31, 2016 and assessed the following attributes: (1) contextual considerations such as geographic scale and contextual factors used; (2) methods used to quantify contextual factors; and (3) cancer type and outcomes. We searched PubMed, Scopus, and Web of Science and initially identified 1060 studies. One hundred twenty-two studies remained after exclusions.

RESULTS

Most studies utilized a two-level structure; census tracts were the most commonly used geographic scale. Socioeconomic factors, health care access, racial/ethnic factors, and rural-urban status were the most common contextual factors addressed in multilevel models. Breast and colorectal cancers were the most common cancer types, and screening and staging were the most common outcomes assessed in these studies.

CONCLUSIONS

Opportunities for future research include deriving contextual factors using more rigorous approaches, considering cross-classified structures and cross-level interactions, and using multilevel modeling to explore understudied cancers and outcomes.

Comparing multilevel and multiscale convolution models for small area aggregated health data

In spatial epidemiology, data are often arrayed hierarchically. The classification of individuals into smaller units, which in turn are grouped into larger units, can induce contextual effects. On the other hand, a scaling effect can occur due to the aggregation of data from smaller units into larger units. In this paper, we propose a shared multilevel model to address the contextual effects. In addition, we consider a shared multiscale model to adjust for both scale and contextual effects simultaneously. We also study convolution and independent multiscale models, which are special cases of shared multilevel and shared multiscale models, respectively. We compare the performance of the models by applying them to real and simulated data sets. We found that the shared multiscale model was the best model across a range of simulated and real scenarios as measured by the deviance information criterion (DIC) and the Watanabe Akaike information criterion (WAIC).

Contextually Aided Recovery (CARe): a scientific theory for innate healing

BACKGROUND

The chiropractic profession emerged when scientific explanations for causes of health and disease were still in infancy and the co-existence of notions such as innate healing and vitalism were perhaps admissible within such a historical context. Notwithstanding, within the scientific culture of the 21^st Century all healthcare paradigms require evidential support which in regard these early concepts are in large part, absent. Nevertheless, a large body of emerging scientific evidence supports the existence of innate healing phenomena that may explain a plethora of clinical outcomes observed during chiropractic care. However, in contrast to the notion that removing the putative subluxation constitutes the mechanism by which this healing is initiated, the evidentially supported explanation is one that invokes the impact of contextual factors inherent in the skilful care and authority of the healthcare provider. This perspective is presented here as the scientific model of Contextually Aided Recovery (CARe).

MAIN BODY

This paper contends that;Contextual effects are powerful and desirable and are triggered by contextual factors present in all therapeutic encounters including those encountered in chiropractic practice.These factors can elicit large clinical effects with substantive evidence supporting pain, immune and motor modulation.The compartmentalisation of specific and non-specific effects is a biologically and scientifically false dichotomy, erroneously invoked to de-legitimise treatment approaches that expertly construct contextual healing scenarios.The use of factors to construct contextual healing scenarios that maximise positive (placebo) and minimize negative (nocebo) effects is a skilful clinical art within the multimodal approach that describes modern chiropractic care and should be presented and defended as a legitimate component of orthodox healthcare Clinical improvement during chiropractic care, beyond any biologically specific treatment effects of manipulation and other modalities, may be largely understood considering contextual factors as described by a Contextually Aided Recovery (CARe) model.

Social capital, friendship networks, and youth unemployment

Youth unemployment is a contemporary social problem in many societies. Youths often have limited access to information about jobs and limited social influence, yet little is known about the relationship between social capital and unemployment risk among youth. We study the effect of social capital on unemployment risk in a sample of 19 year olds of Swedish, Iranian, and Yugoslavian origin living in Sweden (N = 1590). We distinguish between two dimensions of social capital: occupational contact networks and friendship networks. First, ego's unemployment is found to be strongly associated with friends' unemployment among individuals of Yugoslavian origins and individuals of Swedish origin, but not Iranian origin. Second, occupational contact networks reduce unemployment risks for all groups, but especially so for Iranians. The effect sizes of the two dimensions are similar and substantial: going from low to high values on these measures is associated with a difference of some 60-70 percent relative difference in unemployment risk. The findings are robust to a number of different model specifications, including a rich set of social origin controls, personality traits, educational performance, friends' characteristics, and friendship network characteristics, as well as controls for geographical employment patterns. A sensitivity simulation shows that homogeneity bias need to be very strong to explain away the effect.

Capturing contextual effects in spectro-temporal receptive fields

Spectro-temporal receptive fields (STRFs) are thought to provide descriptive images of the computations performed by neurons along the auditory pathway. However, their validity can be questioned because they rely on a set of assumptions that are probably not fulfilled by real neurons exhibiting contextual effects, that is, nonlinear interactions in the time or frequency dimension that cannot be described with a linear filter. We used a novel approach to investigate how a variety of contextual effects, due to facilitating nonlinear interactions and synaptic depression, affect different STRF models, and if these effects can be captured with a context field (CF). Contextual effects were incorporated in simulated networks of spiking neurons, allowing one to define the true STRFs of the neurons. This, in turn, made it possible to evaluate the performance of each STRF model by comparing the estimations with the true STRFs. We found that currently used STRF models are particularly poor at estimating inhibitory regions. Specifically, contextual effects make estimated STRFs dependent on stimulus density in a contrasting fashion: inhibitory regions are underestimated at lower densities while artificial inhibitory regions emerge at higher densities. The CF was found to provide a solution to this dilemma, but only when it is used together with a generalized linear model. Our results therefore highlight the limitations of the traditional STRF approach and provide useful recipes for how different STRF models and stimuli can be used to arrive at reliable quantifications of neural computations in the presence of contextual effects. The results therefore push the purpose of STRF analysis from simply finding an optimal stimulus toward describing context-dependent computations of neurons along the auditory pathway.

Metonymy as Referential Dependency: Psycholinguistic and Neurolinguistic Arguments for a Unified Linguistic Treatment

We examine metonymy at psycho- and neurolinguistic levels, seeking to adjudicate between two possible processing implementations (one- vs. two-mechanism). We compare highly conventionalized systematic metonymy (producer-for-product: "All freshmen read O'Connell") to lesser-conventionalized circumstantial metonymy ("[a waitress says to another:] 'Table 2 asked for more coffee."'). Whereas these two metonymy types differ in terms of contextual demands, they each reveal a similar dependency between the named and intended conceptual entities (e.g., Jackendoff, 1997; Nunberg, 1979, 1995). We reason that if each metonymy yields a distinct processing time course and substantially non-overlapping preferential localization pattern, it would not only support a two-mechanism view (one lexical, one pragmatic) but would suggest that conventionalization acts as a linguistic categorizer. By contrast, a similar behavior in time course and localization would support a one-mechanism view and the inference that conventionalization acts instead as a modulator of contextual felicitousness, and that differences in interpretation introduced by conventionalization are of degree, not of kind. Results from three paradigms: self-paced reading (SPR), event-related potentials (ERP), and functional magnetic resonance imaging (fMRI), reveal the following: no main effect by condition (metonymy vs. matched literal control) for either metonymy type immediately after the metonymy trigger, and a main effect for only the Circumstantial metonymy one word post-trigger (SPR); a N400 effect across metonymy types and a late positivity for Circumstantial metonymy (ERP); and a highly overlapping activation connecting the left ventrolateral prefrontal cortex and the left dorsolateral prefrontal cortex (fMRI). Altogether, the pattern observed does not reach the threshold required to justify a two-mechanism system. Instead, the pattern is more naturally (and conservatively) understood as resulting from the implementation of a generalized referential dependency mechanism, modulated by degree of context dependence/conventionalization, thus supporting architectures of language whereby "lexical" and "pragmatic" meaning relations are encoded along a cline of contextual underspecification.

ICU-acquired candidemia within selective digestive decontamination studies: a meta-analysis

PURPOSE

To estimate the direct and indirect (contextual) effects of the factorized constituents of selective digestive decontamination and selective oropharyngeal decontamination (SDD/SOD), being topical antibiotic (TA) and protocolized antifungal prophylaxis (PAFP), on ICU-acquired candidemia.

METHODS

A broad range of ICU candidemia incidence studies were sourced to serve as points of reference. The candidemia incidence was extracted from component (control and intervention) groups decanted from studies of various designs (concurrent or non-concurrent) and whether investigating SDD/SOD versus non-TA methods of ICU infection prevention. The candidemia incidences were summarized in regression models using generalized estimating equation (GEE) methods. Groups derived from observational studies (no prevention method under study) provided an overarching external benchmark candidemia incidence for calibration.

RESULTS

Within studies investigating SDD/SOD, the mean (and 95% confidence interval) candidemia incidence among concurrent component groups (40 control; 2.4%; 1.7-3.2% and 43 intervention groups; 2.4%; 1.6-3.1%), but not non-concurrent control groups (11 groups; 1.6%; 0.1-2.7%), is higher than that of the benchmark candidemia incidence derived from 54 observational groups (1.5%; 1.2-1.9%). The TA constituent within SDD/SOD has significant direct and indirect (contextual) effects in GEE models even after adjusting for the publication year and the group-wide presence of either candidemia risk factors or PAFP use.

CONCLUSION

The TA constituent of SDD/SOD is associated with a contextual effect on candidemia incidence which is similar in magnitude to that of the conventional candidemia risk factors and against which PAFP partially attenuates. This increase is inapparent within individual SDD/SOD studies examined in isolation.

Are older adults living in more equal counties healthier than older adults living in more unequal counties? A propensity score matching approach

We assessed the potential contextual effect of income inequality on health by: 1) comparing individuals with similar socioeconomic status (SES) but who reside in counties with different levels of income inequality; and 2) examining whether the potential effect of county-level income inequality on health varies across SES groups. We used the Health and Retirement Study, a nationally representative study of Americans over the age of 50. Using propensity score matching, we selected SES-comparable individuals living in high-income inequality counties and in low-income inequality counties. We examined differences in self-rated overall health outcomes and in other specific physical/mental health outcomes between the two groups using logistic regression (n = 34,994) and imposing different sample restrictions based on residential duration in the area. We then used logistic regression with interactions to assess whether, and if so how, health outcomes differed among participants of different SES groups defined by wealth, income, and education. In bivariate analyses of the unmatched full sample, adults living in high-income inequality counties have worse health outcomes for most health measures. After propensity score matching, adults in high-income inequality counties had worse self-rated health status (AOR = 1.12; 95% CI 1.04-1.19) and were more likely to report diagnosed psychiatric problems (AOR = 1.08; 95% CI 0.99-1.19) than their matched counterparts in low-income inequality counties. These associations were stronger with longer-term residents in the area. Adverse health outcomes associated with living in high-income inequality counties were significant particularly for individuals in the 30(th) or greater percentiles of income/wealth distribution and those without a college education. In summary, after using more precise matching methods to compare individuals with similar characteristics and addressing measurement error by excluding more recently arrived county residents, adults living in high-income inequality counties had worse reported overall physical and mental health than adults living in low-income inequality counties.

The use of multilevel modeling and the level two residual file to explore the relationship between middle years programme student performance and diploma programme student performance

Multilevel modeling has recently found a substantial niche in the context of educational research, although several details about the methodological application of these models have yet to be explored in an achievement data framework. This paper makes use of data provided by the International Baccalaureate (IB) in order to investigate modeling decisions and certain applications of the level two residual file in an effort to increase understanding about the way linear and logistic multilevel models function. The focus of this research is on the relationship between performances in two IB programmes: the Middle Years Programme (MYP) and the Diploma Programme (DP). The impact of predictors on the interpretation of the unconditional and conditional variance-covariance matrix as well as the reliability coefficients is discussed. Empirical findings suggest that students who perform better during MYP moderation tend to perform better on DP exams.