BackgroundThe prevalence of infant obesity is increasing, but there is a lack of evidence-based approaches to prevent obesity at this age. This study tested the acceptability and feasibility of evaluating a theory-based intervention aimed at reducing risk of obesity in infants of overweight/obese women during and after pregnancy: the Healthy and Active Parenting Programme for Early Years (HAPPY).MethodsA feasibility randomised controlled trial was conducted in Bradford, England. One hundred twenty overweight/obese pregnant women (Body Mass Index [BMI] ≥25 kg/m2) were recruited between 10–26 weeks gestation. Consenting women were randomly allocated to HAPPY (6 antenatal, 6 postnatal sessions: N = 59) or usual care (N = 61). Appropriate outcome measures for a full trial were explored, including: infant’s length and weight, woman’s BMI, physical activity and dietary intake of the women and infants. Health economic data were collected. Measurement occurred before randomisation and when the infant was aged 6 months and 12 months. Feasibility outcomes were: recruitment/attrition rates, and acceptability of: randomisation, measurement, and intervention. Intra-class correlations for infant weight were calculated. Fidelity was assessed through observations and facilitator feedback. Focus groups and semi-structured interviews explored acceptability of methods, implementation, and intervention content.ResultsRecruitment targets were met (~20 women/month) with a recruitment rate of 30 % of eligible women (120/396). There was 30 % attrition at 12 months; 66 % of recruited women failed to attend intervention sessions, but those who attended the first session were likely to continue to attend (mean 9.4/12 sessions, range 1–12). Reaction to intervention content was positive, and fidelity was high. Group clustering was minimal; an adjusted effect size of −0.25 standard deviation scores for infant weight at 12 months (95 % CI: −0.16–0.65) favouring the intervention was observed using intention to treat analyses. No adverse events were reported.ConclusionsThe HAPPY intervention appeared feasible and acceptable to participants who attended and those delivering it, however attendance was low; adaptations to increase initial attendance are recommended. Whilst the study was not powered to detect a definitive effect, our results suggest a potential to reduce risk of infant obesity. The evidence reported provides valuable lessons to inform progression to a definitive trial.Trial RegistrationCurrent Controlled Trials ISRCTN56735429Electronic supplementary materialThe online version of this article (doi:10.1186/s12889-016-2861-z) contains supplementary material, which is available to authorized users.

Data availabilitySummary statistics generated by COVID-19 Host Genetics Initiative are available online (https://www.covid19hg.org/results/r6/). The analyses described here use the freeze 6 data. The COVID-19 Host Genetics Initiative continues to regularly release new data freezes. Summary statistics for samples from individuals of non-European ancestry are not currently available owing to the small individual sample sizes of these groups, but the results for 23 loci lead variants are reported in Supplementary Table 3. Individual-level data can be requested directly from the authors of the contributing studies, listed in Supplementary Table 1.

BackgroundThe preschool years are considered critical for establishing healthy lifestyle behaviours such as physical activity. Levels of physical activity track through childhood into adulthood and establishing habitual physical activity early in life is therefore vital. Time spent outdoors is associated with greater physical activity and playground interventions have been shown to increase physical activity in school-aged children. There are few preschool, playground-based interventions and these have given inconclusive results. A report published by the UK’s Chief Medical Officer (CMO) highlighted the need for new interventions to promote movement in the early years (0–5 years).ObjectivesThis study aimed to undertake a pilot cluster randomised controlled trial (RCT) of an outdoor playground-based physical activity intervention for parents and their children aged from 18 months to 4 years (Preschoolers in the Playground or PiP) and to assess the feasibility of conducting a full-scale cluster RCT.DesignThe study was a two-armed pilot cluster RCT with economic and qualitative evaluations. Participants were randomised on a 1 : 1 basis to the PiP intervention (n = 83) or usual practice (control;n = 81).SettingBradford, West Yorkshire, UK.ParticipantsChildren aged from 18 months to 4 years.InterventionThe PiP intervention is grounded in behavioural theory (social cognitive theory) and is in accordance with CMO guidance for physical activity in the early years. It is informed by existing literature and data collected from focus groups with parents. The intervention was delivered in primary school playgrounds. Six 30-minute PiP sessions per week were available for 30 weeks; families were encouraged to come to three a week. The 10-week initiation phase was facilitated by a member of school staff and the maintenance phase was unsupervised.Main outcome measuresRecruitment and retention of schools and families to the trial were the main outcome measures. The acceptability of trial procedures and the intervention, the feasibility of collecting health outcome data and the fidelity of the implementation of the intervention were also evaluated. A preliminary assessment of cost-effectiveness and a sample size calculation for a full trial were conducted.ResultsIn total, 37% of schools and 48% of parents approached agreed to take part. Levels of retention were good at 10 and 52 weeks’ follow-up (82.3% and 83.5% respectively). Both the trial procedures and the intervention were acceptable. However, attendance was low during the autumn and winter/spring initiation phases but somewhat better in the summer initiation phase. Attendance was poor throughout all maintenance phases. The accelerometry protocol for measuring physical activity requires modification. The fidelity of intervention implementation was good (81% adherence). The intervention was borderline cost-effective. A sample size of 600 children from 38 schools is required for a full trial.ConclusionA full RCT of the PiP intervention is feasible. The PiP intervention requires some modification, for example running the intervention during the summer term only, but was found to be acceptable to schools and families.Trial registrationCurrent Controlled Trials ISRCTN54165860.FundingThis project was funded by the NIHR Public Health Research programme and will be published in full inPublic Health Research; Vol. 3, No. 5. See the NIHR Journals Library website for further project information.

BackgroundFew evidence-based physical activity interventions for pre-school children are available. This two-armed pilot cluster randomised controlled trial aimed to evaluate the feasibility of conducting a full-scale trial and of delivering an outdoor physical activity intervention for pre-school children.MethodsSchool was the unit of randomisation, and follow-up occurred at 10 and 52 weeks. Trial feasibility was assessed by recruitment, retention and completion rates of primary (daily moderate-to-vigorous physical activity (MVPA)) and secondary (anthropometric, quality of life, self-efficacy) outcomes. Potential effectiveness was assessed for the primary outcome using a linear regression model comparing MVPA between trial arms adjusting for clustering by school. Feasibility of delivering the intervention was assessed by intervention fidelity and attendance. Semi-structured interviews with parents, intervention facilitators, and head teachers explored acceptability and capability to deliver the intervention as well as acceptability of the study design.ResultsRecruitment rates were 37 % of schools (n = 10 schools) and 48 % of pre-school children (n = 164 children). Retention of children to the trial at 52 weeks was 83.5 %. Thirty-nine percent of children had valid primary outcome accelerometer data at baseline and 52 weeks. Response rates for secondary outcome measures ranged from 52 to 88 % at 10 weeks and 59 to 80 % at 52 weeks. The mean difference in daily MVPA between trial arms at 52 weeks was 0.4, 95 % CI 16.3 to 17.0; p = 0.96. Fidelity of intervention implementation was 81 %. Intervention attendance was higher (82 %) during the summer initiation phase compared to autumn/spring initiation (50 %). Parents, facilitators and head teachers found the intervention acceptable and beneficial.ConclusionsRecruitment and retention rates suggest a trial in this outdoor setting with this population was feasible but is weather sensitive. However, strategies to increase accelerometer wear-time would need to be implemented for reliable primary outcome data to be obtained. There was high implementation fidelity by facilitators, and the intervention was seen as acceptable and deliverable. However, attendance was low and preliminary data showed no evidence of intervention effectiveness. A revised intervention, building on the successful elements of this pilot alongside adapting implementation strategies to improve attendance, should therefore be considered.Trial registrationTrial registry name and number: Current Controlled Trials, ISRCTN54165860. Date of registration: 4 September 2012.

In this study, we use first-principles electronic structure calculations to investigate the structural, electronic and magnetic properties of pristine and intrinsic vacancy containing Sr 3 SnO inverse perovskite. The