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Policy PointsIncome is thought to impact a broad range of health outcomes. However, whether income inequality (how unequal the distribution of income is in a population) has an additional impact on health is extensively debated.Studies that use multilevel data, which have recently increased in popularity, are necessary to separate the contextual effects of income inequality on health from the effects of individual income on health.Our systematic review found only small associations between income inequality and poor self‐rated health and all‐cause mortality. The available evidence does not suggest causality, although it remains methodologically flawed and limited, with very few studies using natural experimental approaches or examining income inequality at the national level. Context: Whether income inequality has a direct effect on health or is only associated because of the effect of individual income has long been debated. We aimed to understand the association between income inequality and self‐rated health (SRH) and all‐cause mortality (mortality) and assess if these relationships are likely to be causal. Methods: We searched Medline, ISI Web of Science, Embase, and EconLit (PROSPERO: CRD42021252791) for studies considering income inequality and SRH or mortality using multilevel data and adjusting for individual‐level socioeconomic position. We calculated pooled odds ratios (ORs) for poor SRH and relative risk ratios (RRs) for mortality from random‐effects meta‐analyses. We critically appraised included studies using the Risk of Bias in Nonrandomized Studies – of Interventions tool. We assessed certainty of evidence using the Grading of Recommendations Assessment, Development and Evaluation framework and causality using Bradford Hill (BH) viewpoints. Findings: The primary meta‐analyses included 2,916,576 participants in 38 cross‐sectional studies assessing SRH and 10,727,470 participants in 14 cohort studies of mortality. Per 0.05‐unit increase in the Gini coefficient, a measure of income inequality, the ORs and RRs (95% confidence intervals) for SRH and mortality were 1.06 (1.03‐1.08) and 1.02 (1.00‐1.04), respectively. A total of 63.2% of SRH and 50.0% of mortality studies were at serious risk of bias (RoB), resulting in very low and low certainty ratings, respectively. For SRH and mortality, we did not identify relevant evidence to assess the specificity or, for SRH only, the experiment BH viewpoints; evidence for strength of association and dose–response gradient was inconclusive because of the high RoB; we found evidence in support of temporality and plausibility. Conclusions: Increased income inequality is only marginally associated with SRH and mortality, but the current evidence base is too methodologically limited to support a causal relationship. To address the gaps we identified, future research should focus on income inequality measured at the national level and addressing confounding with natural experiment approaches. [ABSTRACT FROM AUTHOR]

Background: Behavioural weight management programmes are effective in assisting people with overweight or obesity to lose excess body weight. Yet, many still struggle to attain their weight loss goals in such programmes. Little is understood about the factors which impact success in these programmes. Synthesising this data will allow for theory to be developed on how to improve success in such programmes. The main aim of this review will be to extract and synthesise the barriers and facilitators of successful weight loss during participation of behavioural weight loss programmes in adults living with overweight and obesity. Methods: A systematic search of MEDLINE, Embase, PsycINFO, The Cochrane Library and CINAHL will be performed from inception onwards. Studies will also be sought by contacting experts in the field, reference and website searching. Studies will be eligible if the participants are adults living with obesity (population) undertaking or recently completed behavioural weight loss programmes (intervention) with the primary focus of weight loss (outcome). The primary outcomes will be amount of weight lost and information on barriers and/or facilitators to success. The secondary outcomes will be reasons or factors related to attrition and adherence and behaviour change techniques used in programmes. Two reviewers will screen citations and full-text data. Reviewer 1 will screen all, and reviewer 2 will screen a random 50% of articles. Data extraction will be completed by reviewer 1, and 10% will be checked by the research team. Potential conflicts will be resolved through discussion. Data will be synthesised and described narratively to show the characteristics of each study, levels of success and barriers and facilitators during programme participation. A thematic approach will be taken, and themes will be coded against the levels of the socioecological model. Quantitative data will be extracted and categorised according to these themes and presented alongside the qualitative data. Discussion: Our findings can be used to inform how weight loss programmes can be improved to facilitate success in those at risk of failure. Results will be published in a peer-reviewed journal. Systematic review registration: (PROSPERO CRD42019148158 ) [ABSTRACT FROM AUTHOR]

Background: Several systematic reviews have reviewed the evidence relating to nature on aspects of children and adolescent's health and wellbeing; however, none have looked at the associations or effectiveness of attending nature-based early childhood education (ECE). The main objective is to systematically review and synthesise the evidence to determine if nature-based ECE enhances children's health, wellbeing and development. Methods: We will search the following electronic databases (from inception onwards): MEDLINE, Scopus, PsycINFO, ERIC, SportDiscus, Australian Education Index, British Education Index, Child Development and Adolescent studies, and Applied Social Sciences Index and Abstracts. Grey literature will be identified searching dissertations and reports (e.g. Open Grey, Dissertations Theses Database [ProQuest], and Google Scholar). All types of studies (quantitative and qualitative) conducted in children (aged 2–7 years old) attending ECE who had not started education at primary or elementary school will be included. The exposure of interest will be nature-based ECE settings that integrate nature into their philosophy and/or curriculum and environment. The outcomes of interest will be all aspects of the child's physical, cognitive, social and emotional health wellbeing and development. Two reviewers will independently screen full-text articles. The study methodological quality (or bias) will be appraised using appropriate tools. If feasible, a meta-analysis will be conducted using a random-effect model for studies similar in exposure and outcome. Where studies cannot be included in a meta-analysis, findings will be summarised based on the effect directions and a thematic analysis will be conducted for qualitative studies. Discussion: This systematic review will capture the state of the current literature on nature-based ECE for child health, wellbeing and development. The results of this study will be of interest to multiple audiences (including researchers and policy makers). Results will be published in a peer-reviewed journal. Gaps for future research will be identified and discussed. Systematic review registration: PROSPERO CRD42019152582 [ABSTRACT FROM AUTHOR]