Social Science & Medicine

Background: As medicine grows increasingly technological and scientific, biomedical researchers working to bring new knowledge to bear on clinical practice face a key question: when is a new intervention or treatment ready for clinical use? Because this is both a technical and ethical dilemma, it is crucial to examine the social history of how different approaches to this question emerge and the values or assumptions they embed. Methods: We examine the rise and proliferation of an increasingly common framework for assessing the value of new biomedical data or technology, "actionability," through a computational analysis of published scientific literature referencing this and related terms, including topic modeling and Medical Subject Headings (MeSH) term analysis of over 7000 scientific abstracts indexed in PubMed. Results: We find that actionability, as a term, began appearing more commonly in published literature in the mid-2000s, and proliferated throughout the 2010s and into the 20s. While originally used primarily in research on healthcare quality and implementation, the concept's rise in popularity is ultimately driven by uptake in the fields of clinical genetics and oncology. Conclusions: The adoption of actionability in these fields suggests that actionability as a conceptual framework may be most valuable to areas of translational medicine seeking to make sense of increasing amounts of data and technological innovation with differing levels of scientific validity and clinical utility. Recognizing this value, we also caution that actionability drives our attention primarily towards whether a test or piece of information can lead to action, not whether that action has proven benefits. As clinicians and researchers face difficult questions about how to sort through growing amounts of data to generate knowledge that can have a real impact on patient health, empirical bioethics should play a key role in analyzing the trade-offs and impacts of different approaches.

Background: Rising rates of young people Not in Education, Employment, or Training (NEET) in the UK have recently coincided with declining youth physical and mental health but no study has asked whether this reflects a growing proportion of young people with health problems (prevalence) or those with health problems becoming more likely to be NEET (penalty). Methods: Using 15 years of Understanding Society data (2009-23), we analysed 15,242 respondents aged 16-24 (66,160 observations). We employed three complementary approaches: descriptive trends, Blinder-Oaxaca-Kitagawa (BO) probit decomposition comparing 2009-2013 and 2019-2023 against a 2014-2018 reference period, and fixed-effects (FE) Poisson models with lagged health status. Exposures included self-reported health conditions or disability (SRHD), psychological distress , diagnosed conditions and socio-demographic factors. Findings: NEET rates were lowest in 2014-18 (10.5-11.5%) and higher in 2009-13 (12-15%) and 2019-23 (15-16%). Higher prevalence of SRHD, psychological distress, diagnosed depression and multimorbidity explained changes in NEET prevalence across both the 2009-13 to 2014-2018 and 2014-18 to 2019-23 periods. No change in penalty was observed for any health variable across periods, except for an increase in the penalty for SRHD between the 2009-13 to 2014-18 periods. Interpretation: Rising NEET rates among UK youth are driven largely by more young people having physical and psychological ill health. Whilst labour market and education accommodations remain important, reducing NEET rates will require reversing the decline in youth health, not just accommodating it.

Importance: Loneliness is associated with premature mortality and poor mental health and was declared an epidemic by the US Surgeon General in 2023, but national surveillance has relied on state-based or experimental online surveys. In 2024, the National Health Interview Survey measured loneliness directly for the first time. Objective: To estimate the national prevalence of loneliness among US adults, identify the sociodemographic groups with the highest burden, and quantify associations with mental health, health status, and health care use. Design: Cross-sectional analysis of the 2024 National Health Interview Survey, a nationally representative household survey conducted continuously from January to December 2024. Setting: US households; face-to-face and telephone interviews. Participants: 32 629 sampled civilian noninstitutionalized adults aged 18 years or older (response rate, 47.9%); 31 470 (96.4%) had valid loneliness data. Exposures: Frequent loneliness, defined as feeling lonely always or usually on a 5-category item (always, usually, sometimes, rarely, never). Main Outcomes and Measures: Survey-weighted prevalence of loneliness overall and by sociodemographic characteristics, and associations of frequent loneliness with serious psychological distress (Kessler 6 scale score 13 or higher), frequent feelings of depression and anxiety, life dissatisfaction, fair or poor self-rated health, receipt of counseling or therapy, cost-related unmet mental health care need, and emergency department use. Results: In 2024, 4.9% (95% CI, 4.6%-5.2%) of US adults, an estimated 12.2 million people, felt lonely always or usually, and 23.7% (95% CI, 23.1%-24.3%), an estimated 59.3 million, felt lonely at least sometimes. Prevalence of frequent loneliness was highest among adults with family income below the federal poverty level (10.3%), adults with disability (13.6%), adults living alone (9.0%), and American Indian or Alaska Native adults (12.2%). Adults aged 65 years or older had the lowest prevalence of any age group (4.0%) and adults aged 18 to 29 years the highest (6.3%). After adjustment for sociodemographic characteristics, frequent loneliness was associated with serious psychological distress (adjusted odds ratio, 14.5; 95% CI, 12.1-17.3), life dissatisfaction (9.0; 95% CI, 7.6-10.8), cost-related unmet mental health care need (4.3; 95% CI, 3.5-5.2), and emergency department use (1.8; 95% CI, 1.5-2.0). Conclusions and Relevance: Loneliness among US adults was patterned by poverty, disability, and household structure rather than older age. These estimates from the nation's principal household health survey provide a benchmark for monitoring loneliness and suggest that strategies for social connection should address material hardship and access to mental health care.

Background: High rates of young people who are not in education, employment or training (NEET) are a major societal concern in the UK. Whilst other studies have highlighted that adolescent health can predict NEET status in young adulthood, robust and recent longitudinal evidence remains limited. Methods: This study used data from the Millennium Cohort Study, a longitudinal study of people born in the UK in the early 2000s, to estimate the extent to which mental health conditions, physical health conditions and health behaviours during adolescence predict NEET status in early adulthood (median age: 23). Co-occurrence of exposures was also considered and population attributable fractions were calculated to account for differences in exposure prevalence. Results: Among 8,374 young people, 12.5% were NEET at age 23; approximately two thirds were seeking work and one third were economically inactive. Estimates adjusted for demographic factors indicated that multiple health exposures increased risk of being NEET at age 23, with mental health conditions predicting greater risk than physical health conditions and health behaviours. For instance, a longstanding mental health condition more than doubled the risk of being NEET (adjusted relative risk [aRR] = 2.39, 95% CIs = 1.85, 3.09), while autism (aRR = 3.60, 95% CIs = 2.69, 4.83) and ADHD (aRR = 3.25, 95% CIs = 2.38, 4.44) more than tripled the risk. A greater number of reported adolescent mental health conditions was associated with greater risk of being NEET in young adulthood. Obesity predicted being NEET at age 23 (aRR = 1.54, 95% CIs = 1.18, 2.01) and obesity accompanied by a mental health condition further increased risk (aRR = 2.01, 95% CIs = 1.38, 2.93). Follow-up analyses indicated that associations between adolescent mental health and young adult NEET status were more pronounced for females than males and for the economically inactive than those seeking work. Conclusions: Findings indicate that adolescent health, especially mental health, strongly predicts being NEET in early adulthood. Early, integrated health and education interventions may help reduce later educational and labour market disengagement.

Background: Multiple observational studies have reported associations between greater parity and increased CVD risk. Whether these associations reflect causal effects or are confounded by socioeconomic factors remains unclear. Methods: We investigated associations between number of children ever born (NEB) and 16 cardiometabolic traits in up to 172,122 females and 138,390 males in the UK Biobank, and an independent sample of 53,237 UK Biobank spousal pairs. We additionally conducted sex-stratified two-sample Mendelian randomization (MR) and applied a novel spousal MR framework, in which an individual's spouse's genotype was used as the instrumental variable to estimate the causal effect of NEB on cardiometabolic health outcomes, as an approach to minimize bias from horizontal pleiotropy. Results: NEB was associated with multiple cardiometabolic traits in the multivariable regression, even after adjustment for socioeconomic status, with differences in the strength of association observed between males and females. Traditional MR provided evidence that higher NEB causally increases type 2 diabetes risk in females, body mass index (BMI) in both sexes, female basal metabolic rate (BMR) and male body fat percentage but decreases female blood pressure. Spousal MR corroborated positive effects on female BMI and BMR and additionally suggested inverse causal effects on female HDL cholesterol and ApoA1 and male blood glucose. Conclusion: These findings indicate a possible causal relationship between NEB and long-term cardiometabolic health, although causal effects are likely to be small.

Background: Young people who are Not in Education, Employment, or Training (NEET) represent a major public health and societal challenge. Existing evidence has linked adolescent mental health problems and health risk behaviours to NEET but has largely treated NEET as a static, rather than longitudinal outcome and overlooked the combined effects of multiple health conditions. Methods: Using data from 5,262 participants born between 1993 and 2000 in the UK Household Longitudinal Study, this study examined the independent and combined associations of adolescent mental health problems (emotional symptoms, conduct problems, hyperactivity) and health risk behaviours (regular smoking, drug use, alcohol use, and high social media use) with ever-NEET status, NEET chronicity, and NEET trajectories from ages 16 to 24, using modified Poisson, proportional odds, and multilevel logistic regression models, respectively. Findings: All mental health problems were associated with ever-NEET status (RRs 1.24-1.27) and NEET chronicity (ORs 1.41-1.98); emotional symptoms showed a widening disadvantage with age, while the disadvantages associated with conduct problems and hyperactivity remained stable. Among health risk behaviours, regular smoking showed the strongest and most persistent relationships with NEET (ever-NEET RR 1.54; chronicity OR 1.64); drug use was related to ever-NEET status (RR 1.37) and an increasing disadvantage after age 21-22, while alcohol use and social media use showed limited associations. NEET risk generally increased with the number of co-occurring conditions, but for recurrent NEET (three or more occasions), risk was only elevated at three or more co-occurring conditions. Interpretation: Adolescent health exposures were associated with NEET risk during ages 16-24, but the strength and pattern varied by exposure and outcome, offering potential insights into the timing and emphasis of any interventions.

Introduction: The preconception period (i.e. the weeks and months before pregnancy) is a critical window during which parental health behaviours can influence pregnancy outcomes and the childs long-term health. Modifiable factors such as nutrition, physical activity, substance use, and environmental exposures play a key role, yet womens ability to adopt and sustain healthy behaviours is shaped by complex psychological, social and environmental influences. This study applies the Theory of Planned Behaviour to identify the beliefs underpinning womens preconception behaviours, with the aim of informing support for effective and sustained health behaviour change. Methods: An Australian national retrospective cross-sectional survey of pregnant women (18-49 years), recruited through social media platforms. The 92-item survey captured respondent socio-demographics, pregnancy status and health conditions, health behaviours, and beliefs regarding preconception health behaviours. Respondents level of pregnancy planning was categorised using the London Measure of Unplanned Pregnancy (LMUP). Items regarding preconception beliefs were structured in accordance with the Theory of Planned Behaviour, with a focus on regular exercise, healthy diet, and alcohol avoidance. These beliefs variables were analysed using structured equation modelling to identify paths between latent variables and the items used to estimate each concept. Results: The study was completed by 430 pregnant women of whom 72.7% had a planned pregnancy. Most had a partner, were university educated and in good health. Structural equation modelling showed intention strongly predicted exercise ({beta}=0.65), healthy diet ({beta}=0.54) and alcohol avoidance ({beta}=0.64). Perceived control and partner norms influenced intentions, whereas health professional norms had limited effect. Positive beliefs were associated with folate supplement use and smoking cessation. Conclusion: These findings highlight intention as a key driver of preconception health behaviours, with perceived control and partner influences playing a more significant role than individual beliefs or health professional input. Effective interventions should therefore address structural barriers and actively involve partners, while respecting womens autonomy. Overall, couples-focused, multi-level strategies are likely essential to support meaningful and sustained preconception health behaviour change.

Background Personal choice, the opportunity to select an action from available options, free from external constraint, significantly affects health, risks, and treatment needs. Unhealthy lifestyles contribute substantially to global disease burden, pressuring health systems and reigniting debate about individual responsibility for health. The COVID-19 pandemic brought these debates into sharp focus. In South Africa's private health sector, vaccine hesitancy persisted where vaccines were freely available, raising questions about fairness when avoidable costs are imposed on others within pooled insurance. This paper develops and applies a structured framework to assess the case for applying personal responsibility(policies linking contributions, coverage, or costs to factors under individual control) using COVID-19 vaccination in a South African insured population. Methods We employed a multi-part approach drawing on administrative claims and vaccination data from approximately 550,000 insured members (March 2020 to December 2022). We examined vaccination on hospitalisation, utilisation, and expenditure; evaluated fairness from utilitarian (cost-effectiveness and cost-utility) and luck egalitarian (choice vs cost distribution) perspectives; assessed the practical feasibility of responsibility-based mechanisms; and integrated findings through a decision framework. Results Vaccination was associated with >90% lower hospitalisation risk, shorter stays, and 35 to 55% lower costs. Cost-utility analysis showed vaccination dominated non-vaccination (more QALYs at lower cost). Predictive modelling indicated non-vaccination in higher-risk groups reflected personal choice rather than constrained circumstance. Observed costs exceeded modelled costs (if all vaccinated) by 22%, concentrated among older adults and those with comorbidities. Practical assessment identified a hierarchy from low-risk vaccination rewards to higher-risk surcharges and benefit restrictions. Conclusion Vaccination was impactful and cost-effective; non-vaccination in higher-risk groups reflected personal choice. Responsibility-sensitive approaches may be justified where choice is demonstrable, impacts clear, and mechanisms proportionate, fair, and feasible. Incentive-based mechanisms offer lower-risk starting points than punitive designs. The framework offers policymakers a tool to weigh accountability, fairness, and solidarity in health-financing policy. Key Words COVID-19 vaccination; personal responsibility; luck egalitarianism; health insurance; South Africa; priority-setting

Demand for preventative health care is weak in low-income settings. In a field experiment in a low-income, high-risk setting, we evaluated whether demand for a new bio-medical preventative health product, offered free at public health clinics, responds to digital feedback-based intensive information on health risks and benefits of prevention along with a clinic referral enabling access to the product. In our sample of women aged 18-24 years, we find a large correction in risk beliefs sustained six months after the intervention. Against a background of very low baseline usage, within six months we find a 5.8 percentage point increase in take up of the prevention method, a level of uptake which is very large relative to the control group. Reassuringly, there is no meaningful difference in up-take amongst baseline high- risk and low-risk individuals.

Background Child marriage/cohabitation before 18 years of age disproportionately affects girls worldwide, but its impacts on mental health are poorly understood. Existing research is mostly cross-sectional, hence unable to estimate causal impacts or longer-term outcomes of child marriage. Methods We analysed longitudinal cohort data across Ethiopia, India, Peru, and Vietnam from Young Lives to investigate the relationship between child marriage/cohabitation and life satisfaction and emotional symptoms. We used linear regression, difference-in-differences estimation (DiD), and propensity score matching (PSM) to examine short and longer-term impacts from age 19 to 29. Findings Across countries 5% (Peru) to 20% (India) of girls were child brides. Child marriage/cohabitation predicted lower life satisfaction -- pooled estimates at age 19 (-0.25 [95%CI=0.40,-0.10]), across 19-29 (-0.22 [95%CI=-0.32,-0.13]), and heterogeneity estimates suggest consistently negative impacts across countries. However, child brides have lower life satisfaction at age 8 even before marriage occurs, likely due to pre-existing disadvantages such as poverty that increase child marriage likelihood. DiD and PSM analyses confirm that most of the differences are due to pre-existing vulnerability and there is a small additional impact of child marriage on worse life satisfaction at age 19 (pooled matched estimate -0.09 [95%CI=-0.19, 0.00]). No differences in emotional symptoms were observed, nor any differences by age of marriage within the child-married sample. Interpretation Child brides have lower life satisfaction from childhood through to early adulthood, which is mostly explained by prior disadvantages and risk factors, with a small additional impact of child marriage itself.

Rural-urban fertility differences may reflect unequal distributions of education, household resources, union timing, and regional characteristics rather than an independent effect of residence. This study examined whether the rural-urban gap in near-completed fertility among Nigerian women aged 40-49 persisted after accounting for these compositional factors. Data were drawn from 7,370 women in the 2024 Nigeria Demographic and Health Survey. Children ever born were analyzed using weighted descriptive statistics, residence-specific comparisons, and four survey-weighted Poisson generalized linear models with a log link and cluster-robust standard errors. The weighted mean number of children ever born was 5.53, ranging from 4.68 among urban women to 6.39 among rural women. In the age-adjusted model, rural women had 37% more children than urban women (IRR = 1.37, p < .001), but residence was no longer statistically significant after adjustment for education and household wealth. In the fully adjusted model, women aged 45-49 had more children than those aged 40-44 (IRR = 1.09, p < .001). Secondary and higher education were associated with lower fertility (IRR = 0.92 and 0.82, respectively; p < .001), as was residence in the richest households (IRR = 0.84, p < .001). First cohabitation at ages 20-24 and 25 or older was also associated with lower fertility (IRR = 0.82 and 0.64; p < .001). The rural-urban fertility gap largely reflected socioeconomic, marital-timing, and regional inequalities.

Importance: Preschool children in care are at high risk for psychosocial health concerns. Population-based evidence is limited. Objective: Estimate prevalence of psychosocial health concerns in children in care and not in care, and assess care-status differences stratified by deprivation. Design: Population-based cross-sectional study using 27-30 Month Health Review data from April 2013 to March 2023. Setting: Universal health review program in Scotland. Participants: 7887 children in care and 445 547 children not in care. Exposures: Care status at review, classified as in care or not. Main Outcomes and Measures: Four outcome categories (emotional, behavioral, and/or attentional; personal and/or social; speech, language, and/or communication; and other developmental concerns) plus an aggregate indicator of any of the four. We estimated adjusted odds ratios between children in care and not in care, including variation with deprivation. Models adjusted for sex, age, ethnicity, and deprivation. Results: Psychosocial health concerns were more common in children in care (2290; 29.0%) than children not in care (77 836; 17.5%; relative risk 1.66). Concerns were more common in children in care across all outcomes. The adjusted odds ratio comparing children in care with children not in care for any recorded concern was 1.86 (95% CI, 1.77-1.96). Adjusted odds ratios varied by outcome from 1.57 (95% CI, 1.49-1.66) for speech, language, and/or communication concerns to 2.49 (95% CI, 2.34-2.66) for emotional, behavioral, and/or attentional concerns. Relative inequities between children in care and not in care decreased with increasing deprivation from aOR of 1.58 (95% CI, 1.45-1.72) in the most deprived fifth of areas to 2.61 (95% CI, 2.25-3.03) in the least deprived fifth. Prevalence of any recorded concern increased with deprivation in both care groups. The relative risk comparing the most deprived with least deprived fifth of areas was 1.46 (95% CI, 1.29-1.66) among children in care and higher at 2.34 (95% CI, 2.29-2.40) among children not in care. Conclusions and Relevance: Psychosocial health inequities are evident at an early age between children in care and not in care, and vary with deprivation. Support for children in care and children living in more deprived areas should be prioritized.

Importance: Oral healthcare is often financed outside universal medical coverage, leaving working-age adults exposed to out-of-pocket costs. People with long-term disability may face added financial, physical, and service barriers to care, but longitudinal evidence on disability and oral healthcare unaffordability is limited. Objective: To estimate the effect of time-varying long-term disability on oral healthcare unaffordability among working-age adults in Australia. Design: Longitudinal cohort study using Household, Income and Labour Dynamics in Australia survey data from waves 18 to 22 (2018-2022), analysed with targeted maximum likelihood estimation for longitudinal modified treatment policies. Setting: Nationally representative household panel survey in Australia. Participants: Adults aged 25 to 65 years at wave 18 who could validly contribute to the longitudinal analysis (identified using HILDA longitudinal weights) and had complete baseline covariate data. Exposure: Time-varying self-reported disability at waves 18 to 21 (2018-2022), defined as any long-term health condition, impairment, or disability restricting everyday activities and lasting, or likely to last, for at least 6 months. Hypothetical interventions comprised 50% and 25% reductions in the odds of disability at each wave, and deterministic sustained disability and no disability regimes. Main Outcome and Measure: Self-reported avoidance of dental treatment because of cost at wave 22 (2022). Results: The analytic sample included 9635 adults; 4901 (50.9%) were female, mean age was 44 (SD=12) years, and 2419 (25.1%) reported disability at baseline. A total of 399 participants (4.1%) reported oral healthcare unaffordable at wave 22 follow-up. Compared with the natural course, sustained disability increased the risk of unaffordability (risk ratio [RR], 1.60; 95% CI, 1.15-2.22). No disability at any time point reduced the risk (RR, 0.59; 95% CI, 0.45-0.77). Reducing the odds of disability by 50% and 25% also reduced the risk of oral healthcare unaffordability by 28% (RR, 0.72; 95% CI, 0.65-0.81) and 17% (RR, 0.83; 95% CI, 0.78-0.89), respectively. Conclusions and Relevance: Under the study assumptions, long-term disability was estimated to increase experienced unaffordability of oral healthcare among working-age Australians. Population level policy responses should address both the upstream conditions that shape disability trajectories and the downstream exclusion of adult dental care from routine financial protection.

Background Personal choice in health behaviours raises difficult questions: when individuals freely decline effective preventive interventions, who should bear the resulting costs? This tension is acute in insurance systems where resources are pooled, yet all health systems pursuing Universal Health Coverage must navigate the boundary between collective solidarity and individual accountability. During the COVID-19 pandemic, vaccines were freely available to members of South African private medical schemes, creating conditions in which non-vaccination could plausibly be examined as a matter of personal choice rather than constrained access. This study applied a luck egalitarian framework to assess whether non-vaccination reflected personal choice or constrained circumstance, and to quantify resulting excess costs. Methods A contextual review assessed barriers to vaccination. Using de-identified claims data for approximately 550,000 individuals (March 2020 to December 2022), logistic regression estimated each person's predicted probability of vaccination based on demographic and clinical factors, with observed and predicted rates compared across strata to infer choice versus circumstance. A zero-inflated negative binomial model estimated predicted expenditure among vaccinated members, applied to the full population to simulate universal vaccination. Excess costs were calculated across predicted probability strata. Results Predicted and observed vaccination rates were closely aligned, suggesting that residual non-vaccination in higher-probability groups reflected personal choice rather than constrained circumstance. Observed costs exceeded predicted costs by 22% under universal vaccination, concentrated among older adults and those with comorbidities. Among those with a 60 to 70% predicted probability of vaccination, observed costs exceeded predicted costs by 127.6%. In contrast, among younger, low-risk members, predicted costs slightly exceeded observed expenditure, as vaccination costs were not offset by reduced hospitalisation. Conclusion Risk pooling depends on solidarity, yet non-vaccination due to personal choice shifts costs in ways that challenge fairness in community-rated insurance. These findings highlight the need for transparent deliberation about when personal responsibility should inform equitable health financing design.

Objectives Increased risk of childhood obesity up to age six years has been linked to higher maternal allostatic load (AL), the physical manifestation of repeated stress exposure. However, associations are less evident when using psychological stress indicators, and data mainly come from higher income countries. Using psychological and physiological stress markers, this study evaluates maternal stress exposures and child risk of obesity in Peruvian women and their children, ages 5 to 15 years, living in a disadvantaged urban area. Methods Maternal stress exposures included mental distress (12-item General Health Questionnaire scores of 5+ for moderate/high and <5 for no/low distress) and AL (lower/moderate/higher AL assessed from Latent Profile Analysis of hair cortisol, BMI, waist circumference, systolic and diastolic blood pressure). Child outcomes included BMI-for-age and waist circumference-for-age z scores (BAZ and WCAZ). Linear regression analyses were conducted, adjusting for confounders and reported as coefficients and 95% confidence intervals (95% CI). Results Versus mothers with no/low distress, those with moderate/high distress had children with 0.40 (95% CI: -0.66,-0.13) and 0.32 lower (-0.53,-0.11) child BAZ and WCAZ respectively. Versus lower AL mothers, moderate AL mothers had children with 1.15 (0.41,1.88) and 0.74 (0.20,1.28) greater BAZ and WCAZ while higher AL mothers had children with 1.43 (0.95,1.92) and 0.91 (0.50,1.32) greater BAZ and WCAZ respectively. Conclusions Children of mothers with higher AL were at greater risk of overweight or obesity, which may add to the rising burdens of non-communicable diseases in resource-constrained settings as well as the related social, economic, and public health costs.

Objective: To evaluate the road safety impact arising from Scotlands 2014 reduction in the legal blood alcohol concentration (BAC) limit for drivers, and to assess whether the effect of the reform varied across different spatial contexts. Design: A quasi-experimental statistical longitudinal study using a Synthetic Difference-in-Differences (SDID) approach. Setting: Small-area panel data for Great Britain, with areas (Middle-layer Super Output Areas, MSOAs, in England and Wales and Intermediate Zones, IZs, in Scotland) classed into control and treatment groups according to whether they were exposed to Scotlands BAC reform. The control and treatment groups comprise 7088 spatial units in England and Wales and 852 spatial units in Scotland, respectively, observed over the period 2008-2019. Participants: The study primarily analyses police-reported road traffic collision data from the UK Department for Transports STATS19 system. Data were analysed at the MSOA/IZ level. This is a secondary dataset, and we therefore did not involve patients or the public in formulating the research question, determining outcome measures, or designing and conducting the study. Main Outcome Measures: The main outcome measures were log-transformed rates of total road traffic crashes, and (weekend) night-time crashes (22:00-04:00) per 100,000 population. The latter is used as a proxy measure for drunk driving. Results: Our results indicate that the reduction in the legal BAC limit led to statistically significant declines in road traffic crash rates. Aggregate estimates suggest reductions of 12.0% (95% confidence interval (CI): [-13.7%, -10.3%]) in total crashes, 15.6% (95% CI: [-20.7%, -10.2%]) in night-time crashes, and 12.4% (95% CI: [-16.7%, -7.9%]) in weekend night-time crashes. We also find substantial heterogeneity in treatment effects across spatial contexts. Effects were strongest in rural and less densely populated areas, where reductions exceeded 16% (95% CI: [-18.7%, -13.9%]) for total crashes and reached up to 29.6% (95% CI: [-35.8%, -22.8%]) for night-time and 21.4% (95% CI: [-28.3%, -13.9%]) for weekend night-time crashes. Moderate but statistically significant effects were also observed in dense urban areas, whereas effects in suburban and transitional areas were smaller and not statistically significant. Conclusions: Our analysis suggests that lowering the legal BAC limit in Scotland led to meaningful reductions in road traffic crashes, particularly during higher-risk periods and in rural areas. The findings further suggest that the effectiveness of BAC regulation may vary across local contexts, highlighting the importance of accounting for spatial heterogeneity when evaluating road safety policies.

Background: Research consistently shows that colorectal cancer (CRC) screening uptake is socially patterned; however, sociodemographic determinants are usually analysed separately, overlooking how multiple social conditions jointly shape inequalities. This also applies to policy research, where heterogeneity in screening programme effects remains underexplored. Methods: Using data from the European Health Interview Survey (2014 and 2019; n=201,214; 24 countries), we applied Multilevel Analysis of Individual Heterogeneity and Discriminatory Accuracy (MAIHDA) to analyse CRC screening uptake across 72 subgroups defined by sex, education, living arrangement and employment. To assess heterogeneity in screening programme effects, we combined MAIHDA with difference-in-differences (MAIHDA-DiD). Results: MAIHDA revealed inequalities in uptake: lower- and middle-educated men, whether employed or unemployed, had the lowest uptake, whereas men and women not living alone, retired or living with disability, had the highest uptake. Lower-educated homemaker women were the only female group with below-average uptake. MAIHDA-DiD showed that programmes increased overall uptake but did not produce larger gains among groups with lower pre-intervention uptake, and therefore did not reduce inequalities. Instead, programmes generated above-average increases among groups with higher pre-intervention uptake, particularly lower- and middle-educated men and women not living alone and retired. Living arrangement explained more variation in programme effects than other factors, with individuals living alone benefiting less from the programmes. Conclusion: CRC programmes did not reduce (and may have widened) inequalities, underscoring the need for equity-focused strategies in population-based screening. By extending MAIHDA with difference-in-differences, this study introduces a novel approach for evaluating heterogeneous policy effects in public health.

Background Preventing sexually transmitted re-infections brings health benefits and can be significantly less costly than treating their sequelae. Safetxt is a potential novel digital intervention developed to promote safer sexual behaviours. However, a recent randomised controlled trial of safetxt found no effect on reinfection at 1 year (OR 1.13, 95%CI: 0.98-1.31). We investigated if safetxt's effect was mediated through sexually risky behaviours. Methods We used data from 6248 young people with STIs from 92 UK sexual health clinics. The direct and indirect effects of safetxt on reinfection were estimated using the counterfactual approach. Condom use at last sexual encounter, number of sexual partners and STI testing were assessed as mediators. These were analysed singly and together, using regression models and a formal weighting approach. The assumptions of each approach were considered and tested. Analyses were repeated in the subgroup showing the most promising effect of safetxt: men who have sex with men or with men and women (MSM/MSMW). Results No evidence was found for the total, indirect or direct effects differing from the null. Despite not being significant, for MSM/MSMW, some of safetxt's effect on reducing reinfection was identified as being offset through its effect on number of sexual partners. Conclusions There was no evidence that safetxt's effect on reinfection was mediated through changes in sexually risky behaviours. Adaptations to specifically target these behaviours are unlikely to improve safetxt's overall effect. However, improving safetxt's effect on the number of sexual partners a participant has may improve its effect for MSM/MSMW.

Research on adverse childhood experiences (ACEs) has largely relied on retrospective and predominantly adult-focused models that conceptualize mental health difficulties as outcomes of past adversities operating through linear causal pathways. Less is known about how adolescents themselves understand the mechanisms linking adversity and mental health. This study explored young peoples lived experiences of these mechanisms using participatory arts-based methods. Sixty-two young people aged 10-24 years from diverse and often underrepresented backgrounds across England participated in trauma-informed creative workshops. Workshops incorporated multiple artistic modalities, including visual arts, animation, drama, dance, music, film, and creative writing, generating experiential and conversational data. Data were analysed using Framework Analysis within a critical realist approach. Young people did not primarily describe their mental health through narratives linking past adverse events to current outcomes. Instead, they emphasized present-day relational, environmental, and institutional conditions as the most salient influences on wellbeing. Two interconnected pathways were identified: system failures and seeking restoration. System failures referred to ongoing experiences of invalidation, bullying, sensory overwhelm, masking of identity, and unresponsive educational or mental health systems that generated feelings of unsafety. Seeking restoration encompassed actively pursued experiences of belonging, community, validation, sensory regulation, nature connection, creative expression, trust, and authenticity that supported wellbeing. Across pathways, felt (un)safety emerged as the central organizing mechanism through which experiences affected mental health. Findings suggest that adolescents explain their mental health less in terms of historical adversity and more through current experiences of safety, recognition, and belonging. Trauma-informed research and practice may therefore benefit from complementing questions about past adversity with greater attention to what is happening in young peoples lives now and the conditions that support recovery and flourishing.

Abstract Objective To describe variation in hospital costs among children with different combinations of health conditions, special educational needs or disability (SEND) and children social care (CSC) indicators. Study Setting and Design This cross-sectional study used regression analysis to test whether two-way and three-way interactions of cross-public sector service use (health, education and social care) are associated with higher hospital costs in England. Data Sources and Analytic Sample Hospital care costs between April 2022 and March 2023 for the 8.9 million children aged 5-18 years were obtained from linked administrative hospital, education or social care data in the ECHILD database. Children were classified into eight categories based on combinations of indicators of chronic health conditions, SEND or CSC. Principal Findings Over one-third (35.4%) of children had some hospital costs during the year. Average costs were 317GBP for all children and 895GBP for children with non-zero hospital costs. By age 18, few children had no indicator in any sector (35.1% of boys, 43.7% of girls) and indicators in all three sectors were not rare (7.1% of boys, 6.2% of girls). At age 5, children with indicators recorded in all three sectors had the highest hospital costs (2,952GBP for boys and 3,674GBP for girls). At age 18, males and females with indicators in all three sectors accounted for 21% and 23% of hospital costs, respectively. SEND and social care indicators without chronic health conditions were associated with only slightly higher hospital costs. Hospital costs were much higher for children with SEND if they also had a chronic health condition. Hospital costs were only higher for children with social care if they also had both a chronic health condition and SEND. Conclusions. Taking account of additional support from non-health sectors is important for understanding health sector costs. The compounding associations between use of other public sectors on health sector costs indicates scope for targeting of integrated care.