Producing Change to Understand the Social Determinants of Health: The Promise of Experiments for Social Epidemiology.

In this commentary, invited for the 100th anniversary of the Journal, we discuss the addition of randomized experiments, along with natural experiments that emulate randomized trials using observational data, as designs in the social epidemiologist's toolbox. These approaches transform the way we define and ask questions about social exposures. They compel us to ask questions about how well-defined interventions change a social exposure that might lead to changes in health. As such, experiments are of unique public health and policy significance. We argue that they are a powerful approach to advance our understanding of how well-defined changes in social exposures impact health, and how credible social policy reforms may be instrumental to address health inequalities. We focus on two research designs. The first is a "pure" randomized controlled trial (RCT) in which the investigator defines and randomly assigns the intervention. The second is a natural experiment, which exploits the fact that policies or interventions in the real world often involve an element of random assignment, emulating an RCT. To give the reader our bottom line: While acknowledging their limits, we continue to be very excited about the promise of RCTs and natural experiments to advance social epidemiology.

Effect of Expanding the Earned Income Tax Credit to Americans Without Dependent Children on Psychological Distress.

Antipoverty policies have the potential to improve mental health. We conducted a randomized trial (Paycheck Plus Health Study Randomized Controlled Trial, New York, New York) to investigate whether a 4-fold increase in the Earned Income Tax Credit for low-income Americans without dependent children would reduce psychological distress relative to the current federal credit. Between 2013 and 2014, a total of 5,968 participants were recruited; 2,997 were randomly assigned to the treatment group and 2,971 were assigned to the control group. Survey data were collected 32 months postrandomization (n = 4,749). Eligibility for the program increased employment by 1.9 percentage points and after-bonus earnings by 6% ($635/year), on average, over the 3 years of the study. Treatment was associated with a marginally statistically significant decline in psychological distress, as measured by the 6-item Kessler Psychological Distress Scale, relative to the control group (score change = -0.30 points, 95% confidence interval (CI): -0.63, 0.03; P = 0.072). Women in the treated group experienced a half-point reduction in psychological distress (score change = -0.55 points, 95% CI: -0.97, -0.13; P = 0.032), and noncustodial parents had a 1.36-point reduction (95% CI: -2.24, -0.49; P = 0.011). Expansion of a large antipoverty program to individuals without dependent children reduced psychological distress for women and noncustodial parents-the groups that benefitted the most in terms of increased after-bonus earnings.

Adult Child Schooling and Older Parents' Cognitive Outcomes in the Survey of Health, Aging and Retirement in Europe (SHARE): A Quasi-Experimental Study.

A growing body of research suggests that adult child educational attainment benefits older parents' cognitive outcomes via financial (e.g., direct monetary transfers) and nonfinancial (e.g., psychosocial) mechanisms. Quasi-experimental studies are needed to circumvent confounding bias. No such quasi-experimental studies have been completed in higher-income countries, where financial transfers from adult children to aging parents are rare. Using data on 8,159 adults aged ≥50 years in the Survey for Health, Aging and Retirement in Europe (2004/2005), we leveraged changes in compulsory schooling laws as quasi-experiments. Each year of increased schooling among respondents' oldest children was associated with better verbal fluency (ß = 0.07, 95% CI: 0.02, 0.12) scores; overall associations with verbal memory scores were null, with mixed and imprecise evidence of association in models stratified by parent gender. We also evaluated associations with psychosocial outcomes as potentially important mechanisms. Increased schooling among respondents' oldest children was associated with higher quality-of-life scores and fewer depressive symptoms. Our findings present modest albeit inconsistent evidence that increases in schooling may have an "upward" influence on older parents' cognitive performance even in settings where financial transfers from adult children to their parents are uncommon. Associations with parents' psychosocial outcomes were more robust.

Can Social Policies Improve Health? A Systematic Review and Meta-Analysis of 38 Randomized Trials.

Policy Points Social policies might not only improve economic well-being, but also health. Health policy experts have therefore advocated for investments in social policies both to improve population health and potentially reduce health system costs. Since the 1960s, a large number of social policies have been experimentally evaluated in the United States. Some of these experiments include health outcomes, providing a unique opportunity to inform evidence-based policymaking. Our comprehensive review and meta-analysis of these experiments find suggestive evidence of health benefits associated with investments in early life, income support, and health insurance interventions. However, most studies were underpowered to detect health outcomes. CONTEXT: Insurers and health care providers are investing heavily in nonmedical social interventions in an effort to improve health and potentially reduce health care costs. METHODS: We performed a systematic review and meta-analysis of all known randomized social experiments in the United States that included health outcomes. We reviewed 5,880 papers, reports, and data sources, ultimately including 61 publications from 38 randomized social experiments. After synthesizing the main findings narratively, we conducted risk of bias analyses, power analyses, and random-effects meta-analyses where possible. Finally, we used multivariate regressions to determine which study characteristics were associated with statistically significant improvements in health outcomes. FINDINGS: The risk of bias was low in 17 studies, moderate in 11, and high in 33. Of the 451 parameter estimates reported, 77% were underpowered to detect health outcomes. Among adequately powered parameters, 49% demonstrated a significant health improvement, 44% had no effect on health, and 7% were associated with significant worsening of health. In meta-analyses, early life and education interventions were associated with a reduction in smoking (odds ratio [OR] = 0.92, 95% confidence interval [CI] 0.86-0.99). Income maintenance and health insurance interventions were associated with significant improvements in self-rated health (OR = 1.20, 95% CI 1.06-1.36, and OR = 1.38, 95% CI 1.10-1.73, respectively), whereas some welfare-to-work interventions had a negative impact on self-rated health (OR = 0.77, 95% CI 0.66-0.90). Housing and neighborhood trials had no effect on the outcomes included in the meta-analyses. A positive effect of the trial on its primary socioeconomic outcome was associated with higher odds of reporting health improvements. We found evidence of publication bias for studies with null findings. CONCLUSIONS: Early life, income, and health insurance interventions have the potential to improve health. However, many of the included studies were underpowered to detect health effects and were at high or moderate risk of bias. Future social policy experiments should be better designed to measure the association between interventions and health outcomes.

Public Transportation Use and Cognitive Function in Older Age: A Quasiexperimental Evaluation of the Free Bus Pass Policy in the United Kingdom.

In this quasiexperimental study, we examined whether the introduction of an age-friendly transportation policy-free bus passes for older adults-increased public transport use and in turn affected cognitive function among older people in England. Data came from 7 waves (2002-2014) of the English Longitudinal Study of Ageing (n = 17,953), which measured total cognitive function, memory, executive function, and processing speed before and after the bus pass was introduced in 2006. The analytical strategy was an instrumental-variable approach with fixed effects, which made use of the age-eligibility criteria for free bus passes and addressed bias due to reverse causality, measurement error, and time-invariant confounding. Eligibility for the bus pass was associated with a 7% increase in public transport use. The increase in public transportation use was associated with a 0.346 (95% confidence interval: 0.017, 0.674) increase in the total cognitive function z score and with a 0.546 (95% confidence interval: 0.111, 0.982) increase in memory z score. Free bus passes were associated with an increase in public transport use and, in turn, benefits to cognitive function in older age. Public transport use might promote cognitive health through encouraging intellectually, socially, and physically active lifestyles. Transport policies could serve as public health tools to promote cognitive health in aging populations.

The Mental Health Benefits of Acquiring a Home in Older Age: A Fixed-Effects Analysis of Older US Adults.

Homeownership is consistently associated with better mental health, but whether becoming a homeowner in later in life has positive psychological benefits has not, to our knowledge, been examined. We assessed whether acquiring a home after age 50 years was associated with depression in a representative sample of older US adults. We used individual fixed-effects models based on data from 20,524 respondents aged ≥50 years from the Health and Retirement Study, who were interviewed biennially during 1993-2010. Depressive symptoms were measured using the 8-item Center for Epidemiologic Studies Depression Scale. Controlling for confounders, becoming a homeowner in later life predicted a decline in depressive symptoms in the same year (ß = -0.0768, 95% confidence interval (CI): -0.152, -0.007). The association remained significant after 2 years (ß = -0.0556, 95% CI: -0.134, -0.001) but weakened afterward. Buying a home for reasons associated with positive characteristics of the new house or neighborhood drove this association (ß = -0.426, 95% CI: -0.786, -0.066), while acquiring a home for reasons associated with characteristics of the previous home or neighborhood, the desire to be closer to relatives, downsizing, or upsizing did not predict mental health improvements. Findings suggest that there are small but significant benefits for mental health associated with acquiring a home in older age.

Intergenerational Socioeconomic Mobility and Adult Depression: The CONSTANCES Study.

ABSTARCT: Using data from the nationally representative Consultants des Centres d'Examens de Santé (CONSTANCES) study in France (2012-2014; n = 67,057), we assessed the relationship between intergenerational socioeconomic mobility and adult depression (Center for Epidemiological Studies-Depression Scale scores of ≥16 in men or ≥20 in women) and antidepressant use. Socioeconomic position was ascertained by occupational grade (childhood: maternal and paternal measures prior to age 15 years combined; adulthood: participant's own). We used logistic regression models adjusted for sociodemographic characteristics, parental history of psychiatric disorders and suicide, health behaviors, and chronic health problems. Compared with the reference group (persistently high socioeconomic circumstances), participants in other groups had elevated levels of depression (for upward mobility, multivariate odds ratios (OR) = 1.21; intermediate socioeconomic position, 1.28; downward mobility, 1.66; persistently low socioeconomic position, 1.82). Downward mobility and persistently low socioeconomic position were also associated with elevated odds of antidepressant use (for downward mobility, multivariate OR = 1.24; for persistently low socioeconomic position, 1.36). In supplementary analyses, the association of socioeconomic mobility with depression was stronger in women than in men and among younger participants (aged 18-29 years) than among older participants. Factors that contribute to depression risk and socioeconomic inequalities in this area appeared to be at play already in childhood; this should be acknowledged by clinicians and policymakers.

MINDMAP: establishing an integrated database infrastructure for research in ageing, mental well-being, and the urban environment.

BACKGROUND: Urbanization and ageing have important implications for public mental health and well-being. Cities pose major challenges for older citizens, but also offer opportunities to develop, test, and implement policies, services, infrastructure, and interventions that promote mental well-being. The MINDMAP project aims to identify the opportunities and challenges posed by urban environmental characteristics for the promotion and management of mental well-being and cognitive function of older individuals. METHODS: MINDMAP aims to achieve its research objectives by bringing together longitudinal studies from 11 countries covering over 35 cities linked to databases of area-level environmental exposures and social and urban policy indicators. The infrastructure supporting integration of this data will allow multiple MINDMAP investigators to safely and remotely co-analyse individual-level and area-level data. Individual-level data is derived from baseline and follow-up measurements of ten participating cohort studies and provides information on mental well-being outcomes, sociodemographic variables, health behaviour characteristics, social factors, measures of frailty, physical function indicators, and chronic conditions, as well as blood derived clinical biochemistry-based biomarkers and genetic biomarkers. Area-level information on physical environment characteristics (e.g. green spaces, transportation), socioeconomic and sociodemographic characteristics (e.g. neighbourhood income, residential segregation, residential density), and social environment characteristics (e.g. social cohesion, criminality) and national and urban social policies is derived from publically available sources such as geoportals and administrative databases. The linkage, harmonization, and analysis of data from different sources are being carried out using piloted tools to optimize the validity of the research results and transparency of the methodology. DISCUSSION: MINDMAP is a novel research collaboration that is combining population-based cohort data with publicly available datasets not typically used for ageing and mental well-being research. Integration of various data sources and observational units into a single platform will help to explain the differences in ageing-related mental and cognitive disorders both within as well as between cities in Europe, the US, Canada, and Russia and to assess the causal pathways and interactions between the urban environment and the individual determinants of mental well-being and cognitive ageing in older adults.

Building the capacity of policy-makers and planners to strengthen mental health systems in low- and middle-income countries: a systematic review.

BACKGROUND: Little is known about the interventions required to build the capacity of mental health policy-makers and planners in low- and middle-income countries (LMICs). We conducted a systematic review with the primary aim of identifying and synthesizing the evidence base for building the capacity of policy-makers and planners to strengthen mental health systems in LMICs. METHODS: We searched MEDLINE, Embase, PsycINFO, Web of Knowledge, Web of Science, Scopus, CINAHL, LILACS, ScieELO, Google Scholar and Cochrane databases for studies reporting evidence, experience or evaluation of capacity-building of policy-makers, service planners or managers in mental health system strengthening in LMICs. Reports in English, Spanish, Portuguese, French or German were included. Additional papers were identified by hand-searching references and contacting experts and key informants. Database searches yielded 2922 abstracts and 28 additional papers were identified. Following screening, 409 full papers were reviewed, of which 14 fulfilled inclusion criteria for the review. Data were extracted from all included papers and synthesized into a narrative review. RESULTS: Only a small number of mental health system-related capacity-building interventions for policy-makers and planners in LMICs were described. Most models of capacity-building combined brief training with longer term mentorship, dialogue and/or the establishment of networks of support. However, rigorous research and evaluation methods were largely absent, with studies being of low quality, limiting the potential to separate mental health system strengthening outcomes from the effects of associated contextual factors. CONCLUSIONS: This review demonstrates the need for partnership approaches to building the capacity of mental health policy-makers and planners in LMICs, assessed rigorously against pre-specified conceptual frameworks and hypotheses, utilising longitudinal evaluation and mixed quantitative and qualitative approaches.

Does schooling attained by adult children affect parents' psychosocial well-being in later life? Using Mexico's 1993 compulsory schooling law as a quasi-experiment.

Higher adult child educational attainment may benefit older parents' psychosocial well-being in later life. This may be particularly important in low- and middle-income countries, where recent generations have experienced comparatively large increases in educational attainment. We used data from the 2012 Mexican Health and Aging Study, a nationally representative study of adults aged ≥50 years and leveraged the exogenous variation in adult child education induced by Mexico's compulsory schooling law passed in 1993. We employed two-stage least squares (2SLS) regression to estimate the effects of increased schooling among adult children on parents' (respondents') depressive symptoms and life satisfaction scores, controlling for demographic and socioeconomic characteristics. We considered heterogeneity by parent and child gender and other sociodemographic characteristics. Our study included 7186 participants with an average age of 60.1 years; 54.9% were female. In the 2SLS analyses, increased schooling among oldest adult children was associated with fewer depressive symptoms (ß = -0.25; 95% CI: -0.51, 0.00) but no difference in life satisfaction (ß = 0.01; 95% CI: -0.22, 0.25). Stratified models indicated differences in the magnitude of association with depressive symptoms for mothers (ß = -0.27, 95% CI: -0.56, 0.01) and fathers (ß = -0.18, 95% CI: -0.63, 0.26) and when considering increased schooling of oldest sons (ß = -0.37; 95% CI: -0.73, -0.02) and daughters (ß = -0.05, 95% CI: -0.23, 0.13). No parent and child gender differences were found for life satisfaction. Power was limited to detect heterogeneity across other sociodemographic characteristics in the second stage although first-stage estimates were larger for urban (vs. rural) dwelling and more (vs. less) highly educated respondents. Results were similar when considering the highest educated child as well as increased schooling across all children. Our findings suggest that longer schooling among current generations of adult children, particularly sons, may benefit their older parents' psychosocial well-being.

Paternity leave uptake and parental post-partum depression: findings from the ELFE cohort study.

BACKGROUND: Several countries are expanding their paternity leave policies, which can have positive effects on parental mental health. We examined whether 2 weeks of paid paternity leave are associated with post-partum depression in mothers and fathers at 2 months after the birth of their child. METHODS: We used data from the Etude Longitudinale Française depuis l'Enfance (ELFE) cohort study. Participating mothers gave birth in 2011 in a representative sample of 320 maternity hospitals in mainland France. Inclusion criteria were single or twin livebirths born after at least 33 weeks' gestation; mother's age at least 18 years; no plans to leave metropolitan France within 3 years. Mothers were interviewed face-to-face shortly after the child's birth. Fathers and mothers were both interviewed by telephone 2 months after the child's birth, reporting whether the father had the right to paternity leave and if yes, if he had taken or intended to take it. We used the Edinburgh Postnatal Depression Scale to assess post-partum depression among fathers and mothers at 2 months. Logistic regression models, using survey-weighted data and adjusted for confounders using inverse probability weights, yielded odds ratios (ORs). FINDINGS: We included 10 975 fathers and 13 075 mothers with reported information on paternity leave and post-partum depression at 2 months in the statistical analyses. Fathers had a median age of 32·6 years (IQR 36·9-22·6) and mothers had a median age of 30·5 years (34·0-27·1) at the time of the ELFE child's birth. The prevalence of depression in fathers according to paternity leave status was 4·5% among those who used paternity leave, 4·8% among those who intended to use paternity leave, and 5·7% among those who did not use paternity leave. For mothers, the prevalence of post-partum depression was 16·1% among those whose partner used paternity leave, 15·1% among those whose partner intended to use paternity leave, and 15·3% among those whose partner did not use paternity leave. Fathers who took paternity leave had reduced odds of post-partum depression (OR 0·74 [95% CI 0·70-0·78]) as did fathers who intended to take paternity leave (0·76 [0·70-0·82]) compared with fathers who did not take paternity leave. However, we did not find such beneficial effects for mothers whose partners took (1·13 [1·05-1·20]) or intended to take paternity leave (1·02 [0·96-1·08]). INTERPRETATION: Taking and intending to take 2-weeks' paid paternity leave was associated with a reduced likelihood of reporting post-partum depression in fathers. However, offering 2-weeks' paternity leave might place mothers at a greater risk of post-partum depression, suggesting that optimal length and timing of the leave, among other factors, need further investigation. FUNDING: The French National Research Agency.

The effect on women's health of extending parental leave: a quasi-experimental registry-based cohort study.

BACKGROUND: Parental leave policies have been hypothesized to benefit mothers' mental health. We assessed the impact of a 6-week extension of parental leave in Denmark on maternal mental health. METHODS: We linked individual-level data from Danish national registries on maternal sociodemographic characteristics and psychiatric diagnoses. A regression discontinuity design was applied to study the increase in parental leave duration after 26 March 1984. We included women who had given birth between 1 January 1981 and 31 December 1987. Our outcome was a first psychiatric diagnosis following the child's birth, ascertained as the first day of inpatient hospital admission for any psychiatric disorder. We presented cumulative incidences for the 30-year follow-up period and reported absolute risk differences between women eligible for the reform vs not, in 5-year intervals. RESULTS: In all, 291 152 women were followed up until 2017, death, emigration or date of first psychiatric diagnosis. The median follow-up time was 29.99 years, corresponding to 10 277 547 person-years at risk. The cumulative incidence of psychiatric diagnoses at 30 years of follow-up was 59.5 (95% CI: 57.4 to 61.6) per 1000 women in the ineligible group and 57.5 (95% CI: 55.6 to 59.4) in the eligible group. Eligible women took on average 32.85 additional days of parental leave (95% CI: 29.20 to 36.49) and had a lower probability of having a psychiatric diagnosis within 5 years [risk difference (RD): 2.4 fewer diagnoses per 1000 women, 95% CI: 1.5 to 3.2] and up to 20 years after the birth (RD: 2.3, 95% CI: 0.4 to 4.2). In subgroup analyses, the risk reduction was concentrated among low-educated, low-income and single women. CONCLUSIONS: Longer parental leave may confer mental health benefits to women, in particular to those from disadvantaged backgrounds.

Effect of covering perinatal health-care costs on neonatal outcomes in Switzerland: a quasi-experimental population-based study.

BACKGROUND: Low birthweight and preterm birth are associated with an increased risk of neonatal death and chronic conditions across the life course. Reducing these adverse birth outcomes is a global public health priority and requires strategies to improve health care during pregnancy. We aimed to assess the effect of a Swiss health policy expansion fully covering illness-related costs during pregnancy on health outcomes in newborn babies. METHODS: We implemented a quasi-experimental difference in regression discontinuity design to assess the effect of expansion of Swiss health insurance (on March 1, 2014), to fully cover health-care costs during pregnancy and 8 weeks postpartum, on neonatal outcomes. Before this reform, only costs specific to the standard monitoring of a normal pregnancy were covered. Babies born before March 1, 2014, and their mothers were assigned to the unexposed group, and babies born on or after March 1, 2014, and their mothers were assigned to the exposed group. We included nearly all children born 2011-19 in Switzerland within a period of 9 months around the date March 1, 2014, and control years 2012, 2016, and 2018. Outcomes were birthweight, low birthweight, very low birthweight, gestational age, preterm or extremely preterm birth, and neonatal death. We estimated the intention-to-treat effect of the policy using parametric regression models. FINDINGS: 61 910 children were born 9 months before and 63 991 were born 9 months after March 1, 2014. 382 861 children were born in the same time period around the three control dates. In the period before policy implementation, mean birthweight was 3289 g, gestational age was 275 days, and 6·5% of children had low birthweight, 1·0% very low birthweight, 7·1% were preterm, 0·4% were extremely preterm, and 0·3% died within the first 28 days of life. After initiation of the policy (vs before) mean birthweight increased by 23 g (95% CI 5 to 40) and the predicted proportion of low birthweight births decreased by 0·81% (0·14 to 1·48) and of very low birthweight births decreased by 0·41% (0·17 to 0·65). The effect on very low birthweight was not robust in sensitivity analyses. The policy had a negligible effect on gestational age (mean difference 1 day, 95% CI 0 to 1) and no clear effects on the other examined outcomes. The change in predicted proportion for preterm births was -0·39% (95% CI -1·2 to 0·38), for extremely preterm births was -0·09% (-0·27 to 0·08), and for neonatal death was -0·07% (-0·2 to 0·07). INTERPRETATION: Free access to prenatal care in Switzerland reduced the risk of some adverse health outcomes in newborn babies. Expanding health-care coverage is a relevant health system intervention to reduce the risk of adverse health outcomes in the newborn baby and, potentially, across the life course. FUNDING: Swiss National Science Foundation.

Increased adult child schooling and older parents' health behaviors in Europe: A quasi-experimental study.

There is growing evidence that adult child educational attainment is associated with older parents' physical health and longevity. Scholars have hypothesized that these associations may be driven by health-behavior pathways, whereby adult children with more education may share information about healthy lifestyles, role-model healthier behaviors, and/or have more economic resources to support leisure-based physical activity or the purchase of healthy foods for older parents. However, this relationship has not been comprehensively evaluated with methods capable of addressing the confounding bias expected for observational studies on this topic. We estimated the association between increased adult child schooling and older parents' health behaviors using data from the Survey for Health, Aging and Retirement in Europe (SHARE) (n = 8195). We leveraged changes to compulsory schooling laws that would have impacted respondents' adult children as quasi-experiments and estimated the association between increased schooling among oldest adult children and respondents' (parents') body mass index, obesity, physical inactivity, excessive drinking, and current smoking using two-stage least squares regression. Each year of increased schooling among oldest adult children was associated with a lower risk of current smoking ( ß : -0.029, 95% CI: -0.056, -0.003), physical inactivity ( ß : -0.034, 95% confidence interval [CI]: -0.077, 0.009), obesity ( ß : -0.038, 95% CI: -0.065, -0.011) and lower body mass index ( ß : -0.37, 95% CI: -0.73, -0.02). The direction of associations with excessive drinking varied by parent gender ( ß : -0.027, 95% CI: -0.046, -0.007 for mothers; ß : 0.068, 95% CI: -0.011, 0.148 for fathers). Increases in adult child schooling may have upward influences on parents' late-life health behaviors, although there may be some differences by parent gender. Findings should be replicated across other global settings and studies should directly evaluate parent health behaviors as mediators of the relationship between increased adult child schooling and older parents' longevity.

Assessing the impact of selective licencing schemes for private rental housing on mental health and well-being: protocol for a mixed-method natural experiment study in Greater London, UK.

INTRODUCTION: The UK private rental housing market has poorer quality housing compared with other sectors and is subjected to calls for better regulation. Poor quality housing poses risks to mental and physical health, and housing improvement can potentially benefit health and well-being. Local authorities have powers to implement selective licencing (SL) schemes in specific localities. Such schemes involve landlord registration, payment of licence fees, local authority inspection and requirements that landlords conduct any necessary renovation works to ensure housing standards are met. We aim to evaluate SL in Greater London and to test the feasibility of a national evaluation. METHODS AND ANALYSIS: We will measure individual-level and area-level impacts of SL in Greater London between 2011 and 2019. A difference-in-differences approach with propensity score-matched controls will be used. We propose to exploit data from the Annual Population Survey (APS) and health and social benefit registers to measure mental health and well-being at individual (self-reported anxiety) and area (Small Area Mental Health Index) level. We estimate 633 APS participants in our intervention groups compared with 1899 participants in control areas (1:3 ratio of intervention to control). Secondary outcomes will be self-reported well-being and residential stability at the individual level and incidence of police-recorded antisocial behaviour calls and population turnover at the area level. The study size of the area-level analyses will be 3684 lower layer super output areas (including controls). Qualitative semistructured interviews with lead implementers in several London boroughs will produce insights into variations and commonalities between schemes. ETHICS AND DISSEMINATION: Ethical approval was obtained from London School of Hygiene and Tropical Medicine's Ethics Committee (reference number 26481) and London Borough of Hackney. All interviewees will be asked for informed written consent. Study findings will be published in a peer-reviewed journal.

Impact of selective licensing schemes for private rental housing on mental health and social outcomes in Greater London, England: a natural experiment study.

OBJECTIVES: To assess primary impact of selective Licensing (SL), an area-based intervention in the private rented housing market, on individual self-reported anxiety and neighbourhood mental health (MHI-Mental Healthcare Index) and secondary impacts on antisocial behaviour (ASB), population turnover and self-reported well-being. DESIGN: Difference-in-difference (DiD) was used to evaluate effects of SL schemes initiated 2012-2018. 921 intervention areas (lower super output areas) were matched 3:1 using propensity scores derived from sociodemographic and housing variables (N=3.684 including controls). Average treatment effect on treated (ATT) was calculated for multiple time period DiD in area-level analyses. Canonical DiD was used for individual-level analysis by year of treatment initiation while adjusting for age, sex, native birth and occupational class. SETTING: Intervention neighbourhoods and control areas in Greater London, UK, 2011-2019. PARTICIPANTS: We sampled 4474 respondents renting privately in intervention areas (N=17 347 including controls) in Annual Population Survey and obtained area-level MHI population data. INTERVENTIONS: Private landlords in SL areas must obtain a licence from the local authority, allow inspection and maintain minimum housing standards. RESULTS: ATT after 5 years was significantly lower for MHI (-7.5%, 95% CI -5.6% to -8.8%) than controls. Antidepressant treatment days per population reduced by -5.4% (95% CI -3.7% to -7.3), mental health benefit receipt by -9.6% (95% CI -14% to -5.5%) and proportion with depression by -12% (95% CI -7.7% to -16.3%). ASB reduced by -15% (95% CI -21% to -8.2%). Population turnover increased by 26.5% (95% CI 22.1% to 30.8%). Sensitivity analysis suggests overlap with effects of London 2012 Olympic regeneration. No clear patterns were observed for self-reported anxiety. CONCLUSIONS: We found associations between SL and reductions in area-based mental healthcare outcomes and ASB, while population turnover increased. A national evaluation of SL is feasible and necessary.

Changes in benzodiazepine use in the French general population after November 2015 terrorist attacks in Paris: an interrupted time series analysis of the national CONSTANCES cohort.

OBJECTIVES: To determine whether the terrorist attacks occurring in Paris on November 2015 have changed benzodiazepine use in the French population. DESIGN: Interrupted time series analysis. SETTING: National population-based cohort. PARTICIPANTS: 90 258 individuals included in the population-based CONSTANCES cohort from 2012 to 2017. OUTCOME MEASURES: Benzodiazepine use was evaluated according to two different indicators using objective data from administrative registries: weekly number of individuals with a benzodiazepine delivered prescriptions (BDP) and weekly number of defined daily dose (DDD). Two sets of analyses were performed according to sex and age (≤50 vs >50). Education, income and area of residence were additional stratification variables to search for at-risk subgroups. RESULTS: Among women, those with younger age (incidence rate ratios (IRR)=1.18; 95% CI=1.05 to 1.32 for BDP; IRR=1.14; 95% CI=1.03 to 1.27 for DDD), higher education (IRR=1.23; 95% CI=1.03 to 1.46 for BDP; IRR=1.23; 95% CI=1.01 to 1.51 for DDD) and living in Paris (IRR=1.27; 95% CI=1.05 to 1.54 for BDP) presented increased risks for benzodiazepine use. Among participants under 50, an overall increase in benzodiazepine use was identified (IRR=1.14; 95% CI=1.02 to 1.28 for BDP and IRR=1.12; 95% CI=1.01 to 1.25 for DDD) and in several strata. In addition to women, those with higher education (IRR=1.22; 95% CI=1.02 to 1.47 for BDP), lower income (IRR=1.17; 95% CI=1.02 to 1.35 for BDP) and not Paris residents (IRR=1.13; 95% CI=1.02 to 1.26 for BDP and IRR=1.13; 95% CI=1.03 to 1.26 for DDD) presented increased risks for benzodiazepine use. CONCLUSION: Terrorist attacks might increase benzodiazepine use at a population level, with at-risk subgroups being particularly concerned. Information and prevention strategies are needed to provide appropriate care after such events.

The Health Effects Of Expanding The Earned Income Tax Credit: Results From New York City.

Antipoverty policies may hold promise as tools to improve health and reduce mortality rates among low-income Americans. We examined the health effects of the New York City Paycheck Plus randomized controlled trial. Paycheck Plus tests the impact of a potential fourfold increase in the Earned Income Tax Credit for low-income Americans without dependent children. Starting in 2015, Paycheck Plus offered 5,968 study participants a credit of up to $2,000 at tax time (treatment) or the standard credit of about $500 (control). Health-related quality of life and other outcomes for a representative subset of these participants (n = 3,289) were compared to those of a control group thirty-two months after randomization. The intervention had a modest positive effect on employment and earnings, particularly among women. It had no effect on health-related quality of life for the overall sample, but women realized significant improvements.