Alkon 2014

Methods	Study design: cluster‐randomised controlled trial Intervention duration: 7 months Length of follow‐up from baseline: 7 months Differences in baseline characteristics: reported Unit of allocation: childcare service Unit of analysis: childcare service (child behaviour and weight status were assessed at the level of the individual)
Participants	Service type: childcare centres Region: California, Connecticut and North Carolina, USA Demographic/socioeconomic characteristics: children between the ages of 3 and 5 years of age from racial/ethnically diverse backgrounds and primarily of low‐income families Inclusion/exclusion criteria: inclusion criteria: English‐speaking service manager, on‐site kitchen, racial/ethnic diversity among the children, participation by at least 60% of families, and a population of children in care primarily comprised of low‐income children between the ages of 3 and 5 years of age Number of services randomised: 18 (9 intervention, 9 control) Numbers by trial group: n (controls baseline) = 9 n (controls follow‐up) = 9 (2 small services under same ownership analysed as 1 service) n (interventions baseline) = 9 n (interventions follow‐up) = 9 Recruitment: Service: 42 childcare services were recruited, of which 24 services did not meet the inclusion criteria. Childcare health consultants from California and North Carolina recruited the convenience sample of services for their respective states while Connecticut services were recruited by the Connecticut principal investigator. Child: Physical activity: 8 children at each service, randomly selected by a statistician BMI: the research assistants selected children at the pre‐intervention period for height and weight measurements from service‐specific randomly ordered lists of enrolled children. Those with pre‐intervention measurements (268) were prioritised for measurement post‐intervention (336); 209 children had useable data at both time points. Recruitment rate: 43%
Interventions	Number of experimental conditions: 2 (intervention, control) Policies, practices or programmes targeted by the intervention: Nutrition and Physical Activity Self‐Assessment for Child Care (NAPSACC) programme including: ‐ Childhood obesity ‐ Healthy eating for young children ‐ Physical activity for young children ‐ Personal health and wellness ‐ Working with families to promote healthy behaviours Implementation strategies: ‐ Workshop: the childcare health consultants facilitated 5 x 1‐hour NAPSACC workshops for child care providers and other staff (e.g. cooks, administrators) at each of the intervention services on i) childhood obesity; ii) healthy eating for young children; iii) physical activity for young children; iv) personal health and wellness; and iv) working with families to promote healthy behaviours ‐ Consultation: childcare health consultants provided at least monthly on‐site consultations and additional phone or email consultations and materials and resources (posters and information sheets on nutrition and physical activities). The childcare health consultants conducted a mean of 11 on‐site visits and 8 off‐site consultations per service over the 7‐month intervention, in addition to the provider and parent workshops. ‐ Policy support: childcare health consultants worked with the service managers to write or update the service nutrition and physical activity policies ‐ Parent workshop: 7 of the intervention services also received the parent workshop “Raising Healthy Kids” Who delivered the intervention: previously trained nurse childcare health consultants Theoretical underpinning: not reported Description of control: delayed NAPSACC intervention in year 2 of the study
Outcomes	Outcome relating to the implementation of childcare service policies, practices or programmes: Service nutrition and physical activity policies: Data collection method: Californian Childcare Health Programme Health and Safety Checklist (CHPHSPC) completed by blinded research assistants and used to determine if the service’s written policies adhered to national guidelines Validity of measures used: unclear ‐ this policy measurement technique was used in another study and was shown to be a valid measure of the effect of childcare health consultant interventions on childcare service environments Provider nutrition and physical activity practices: Data collection method: modified version of the Environment and Policy Assessment and Observation (EPAO) was completed by a research assistant. Mean scores for the nutrition and physical activity scales were calculated for each service then aggregated by intervention and control services Validity of measures used: although these items were modified from a reliable instrument, they were not previously validated in the format included in this study Outcome relating to staff knowledge, skills or attitudes: not applicable Outcome relating to cost: not applicable Outcome relating to adverse consequences: not applicable Outcome relating to child diet, physical activity or weight status: Child physical activity: Data collection method: the Observation System for Recording Activity in Preschools (OSRAP) ‐ Data collection was completed by a trained research assistant. Children were observed in 15‐second intervals for a total of 12 to 16 minutes per child; the observations were conducted over an 8‐hour day. Data were aggregated as the mean percentage of physical activity intensity (1 = stationary to 5 = fast) Validity of measures used: the OSRAP has been validated and has been compared favourably with accelerometer data Child weight status: Data collection method: BMI z‐score ‐ the research assistants used a portable foldable stadiometer to measure height and a digital scale to measure weight. Pre/post BMI z‐score and % underweight, healthy weight, overweight and obese children Validity of measures used: unclear – appears to be an objective measure
Notes	—
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Authors indicate that the services were randomly assigned to treatment groups, but the sequence generation procedure was not described. One control group service that was not able to adequately complete baseline data collection was replaced by a matched service (unclear if this was randomly chosen).
Allocation concealment (selection bias)	Unclear risk	Method of concealment not described.
Blinding of participants and personnel (performance bias) All outcomes	High risk	We assumed that due to the nature of the intervention childcare service staff and study personnel delivering the intervention were not blind to the study allocation and therefore there is a potential high risk of performance bias.
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Outcome assessment was undertaken by blinded research personnel and therefore the risk of detection bias is considered to be low.
Incomplete outcome data (attrition bias) All outcomes	Low risk	Complete data collected for all services (8 control and 9 intervention), with no services excluded from the analysis ‐ therefore risk of attrition bias is considered to be low.
Selective reporting (reporting bias)	Unclear risk	No prospective trial protocol or trial registration so it is unclear whether there was selective outcome reporting.
Recruitment to cluster	Low risk	Selection of participants from each service for measurement of child diet, physical activity and BMI outcomes was random, so risk of bias through selection to cluster is considered to be low.
Baseline imbalance	Unclear risk	There is baseline imbalance in parent and child care provider characteristics but they adjust for some of these in the analysis.
Loss of clusters	Unclear risk	In the control group replaced 1 cluster with a matched cluster and then merged 2 clusters (services that came under same management) for analysis.
Incorrect analysis	Low risk	Hierarchical linear models conducted to assess child‐level BMI z‐score outcomes (accounting for clustering within the service).
Compatibility with individually randomised RCTs	Unclear risk	Unable to determine if a herd effect exists.
Other bias	Unclear risk	—