How to select interventions for promoting physical activity in schools? Combining preferences of stakeholders and scientists

Background The failure to scale-up and implement physical activity (PA) interventions in real world contexts, which were previously successful under controlled conditions, may be attributed to the different criteria of stakeholders and scientists in the selection process of available interventions. Therefore, the aim of our study was to investigate and compare the criteria applied by local stakeholders and scientists for selecting amongst suitable school-based PA interventions for implementation. Methods We conducted a three-round repeated survey Delphi study with local stakeholders (n = 7; Bremen, Germany) and international scientific PA experts (n = 6). Independently for both panels, two rounds were utilized to develop a list of criteria and the definitions of criteria, followed by a prioritization of the criteria in the third round. For each panel, a narrative analysis was used to rank-order unique criteria, list the number of scorers for the unique criteria and synthesize criteria into overarching categories. Results The stakeholders developed a list of 53 unique criteria, synthesized into 11 categories with top-ranked criteria being ‘free of costs’, ‘longevity’ and ‘integration into everyday school life’. The scientists listed 35 unique criteria, synthesized into 7 categories with the top-ranked criteria being ‘efficacy’, ‘potential for reach’ and ‘feasibility’. The top ranked unique criteria in the stakeholder panel were distributed over many categories, whereas four out of the top six criteria in the scientist panel were related to ‘evidence’. Conclusions Although stakeholders and scientists identified similar criteria, major differences were disclosed in the prioritization of the criteria. We recommend an early collaboration of stakeholders and scientists in the design, implementation, and evaluation of PA interventions

Individual participant data (IPD)-level meta-analysis of randomised controlled trials to estimate the vitamin D dietary requirements in dark-skinned individuals resident at high latitude

Context and purpose There is an urgent need to develop vitamin D dietary recommendations for dark-skinned populations resident at high latitude. Using data from randomised controlled trials (RCTs) with vitamin D3-supplements/fortified foods, we undertook an individual participant data-level meta-regression (IPD) analysis of the response of wintertime serum 25-hydroxyvitamin (25(OH)D) to total vitamin D intake among dark-skinned children and adults residing at ≥ 40° N and derived dietary requirement values for vitamin D. Methods IPD analysis using data from 677 dark-skinned participants (of Black or South Asian descent; ages 5–86 years) in 10 RCTs with vitamin D supplements/fortified foods identified via a systematic review and predefined eligibility criteria. Outcome measures were vitamin D intake estimates across a range of 25(OH)D thresholds. Results To maintain serum 25(OH)D concentrations ≥ 25 and 30 nmol/L in 97.5% of individuals, 23.9 and 27.3 µg/day of vitamin D, respectively, were required among South Asian and 24.1 and 33.2 µg/day, respectively, among Black participants. Overall, our age-stratified intake estimates did not exceed age-specific Tolerable Upper Intake Levels for vitamin D. The vitamin D intake required by dark-skinned individuals to maintain 97.5% of winter 25(OH)D concentrations ≥ 50 nmol/L was 66.8 µg/day. This intake predicted that the upper 2.5% of individuals could potentially achieve serum 25(OH)D concentrations ≥ 158 nmol/L, which has been linked to potential adverse effects in older adults in supplementation studies. Conclusions Our IPD-derived vitamin D intakes required to maintain 97.5% of winter 25(OH)D concentrations ≥ 25, 30 and 50 nmol/L are substantially higher than the equivalent estimates for White individuals. These requirement estimates are also higher than those currently recommended internationally by several agencies, which are based predominantly on data from Whites and derived from standard meta-regression based on aggregate data. Much more work is needed in dark-skinned populations both in the dose–response relationship and risk characterisation for health outcomes.Peer reviewe

Development and testing of the BONES physical activity survey for young children

<p>Abstract</p> <p>Background</p> <p>Weight-bearing and high intensity physical activities are particularly beneficial for stimulating bone growth in children given that bone responds favorably to mechanical load. While it is important to assess the contribution and impact of weight-bearing physical activity on health outcomes, measurement tools that quantify and provide information on these activities separately from overall physical activity are limited. This study describes the development and evaluation of a pictorial physical activity survey (PAS) that measures children's participation and knowledge of high-intensity, weight-bearing ("bone smart") physical activity.</p> <p>Methods</p> <p>To test reliability, two identical sets of the PAS were administered on the same day to 41 children (mean age 7.1 ± 0.8 years; 63% female) and compared. To test validity, accelerometry data from 40 children (mean age 7.7 ± 0.8 years; 50% female) were compared to data provided by the PAS. Agreements between categorical and ordinal items were assessed with Kappa statistics; agreements between continuous indices were assessed with Spearman's correlation tests.</p> <p>Results</p> <p>The subjects produced reliable results in all 10 physical activity participation items (κ range: 0.36-0.73, all p < 0.05), but less reliable in answering if the physical activities were "bone smart" (κ range: -0.04-0.66). Physical activity indices, including metabolic equivalent time and weight-bearing factors, were significant in test-retest analyses (Spearman's <it>r </it>range: 0.57-0.74, all p < 0.001). Minutes of very vigorous activity from the accelerometer were associated with the self-reported weight-bearing activity, moderate-high, and high activity scores from the PAS (Spearman's <it>r </it>range: 0.47-0.48, all p < 0.01). However, accelerometer counts, counts per minute, and minutes of moderate-vigorous and vigorous activity were not associated with the PAS scores.</p> <p>Conclusions</p> <p>Together, the results of these studies suggest that the PAS has acceptable test-retest reliability, but limited validity for early elementary school children. This survey demonstrates a first step towards developing a questionnaire that measures high intensity, weight-bearing activity in schoolchildren.</p