Stookey 2017.

Study characteristics
Methods	Study design: cluster‐RCT Length of follow‐up from baseline: 1 year Unit of allocation: centre Unit of analysis: child
Participants	Service type: centre‐based Operation: not reported Country (region): USA (San Francisco) Country income classification: high Low‐SES sample: yes Population description: ECEC centres that primarily serve low‐income children in San Francisco and do not have federal, state or school district funding. Inclusion criteria: all ECEC centres that participated in Child Care Health Program (CCHP) nutrition screenings in 2011–2012 were eligible. Exclusion criteria: ECEC centres that were closed in Autumn 2012 or declined Child Care Health Program (CCHP) services for 2012–2013 before the randomisation were ineligible for the Healthy Apple Program (HAP) pilot. Child‐care centres with funding from Head Start, the San Francisco Unified School District, or Community College District were ineligible to receive CCHP screenings, and excluded from the HAP pilot. ECEC centres that declined one or both BMI screenings in any given year were excluded from evaluation analyses for that year, because of missing data regarding the primary outcome of interest, annual change in BMI between the Autumn and Spring screenings. Children who declined 1 or both screenings or were absent on the date(s) of screening in any given year were excluded from evaluation analyses for that year. Number of services randomised: 43 (19 intervention, 24 control) Number of children randomised: 902 (522 intervention, 380 control) Characteristics Children Age: Intervention: 2 years: 5%; 3 years: 40%; 4 years: 54%; 5 years: 1% Control: 2 years: 14%; 3 years: 40%; 4 years: 45%; 5 years: 0% Gender (% female): not reported Ethnicity: not reported Parents Age (years): not reported Gender (% female): not reported Ethnicity: not reported Parent/family SES: not reported Method of recruitment: the programme was offered to those centres that completed the Child Care Health Program. A USD 25 gift card was offered to 1 representative/child‐care centre for participation in the Healthy Apple Program pilot. Missing data/dropout: 6/43 centres had missing data at follow‐up (2 intervention, 4 control). Reasons for dropout: 3 ineligible for CCHP BMI screenings (1 intervention, 2 control) and 3 declined 1 or both CCHP BMI screenings for the year (1 intervention, 2 control) Characteristics of dropouts: not reported
Interventions	Programme name: Healthy Apple Program (HAP) Number of conditions: 1 intervention, 1 control Intervention duration: 6 months Intervention setting: ECEC Intervention strategies: Health curriculum Children Education: children received nutrition education (circle time for children). Ethos and environment ECEC staff Training: public health nurses or health workers introduced the HAP resources and process, in‐person, to child‐care centre staff and spent up to 16 h per ECEC centre, providing one‐on‐one support to each ECEC provider about the programme. Workshops: 2 x optional, tailored workshops (1 on nutrition, 1 on physical activity) to address participant needs Service Resources: Healthy Apple Program (HAP) resources included an invitation packet, which included information about the HAP, a self‐assessment for ECEC providers, and information about the gift card incentive for completing the self‐assessment. The HAP resources also included a goal‐setting worksheet, hard copy Tip Sheets and online technical assistance materials. Incentive: a USD 25 gift card was offered to 1 representative/ECEC centre for participation in the study. Partnerships Healthcare Health checks: bi‐annual BMI screenings offered by public health nurses or health workers at ECEC centres. Community Co‐ordination: citywide co‐ordination of quality improvement processes for ECEC providers. Intensity of intervention: up to 16 h staff training; 2 x optional workshops Intervention delivered by: ECEC staff, healthcare staff Modality: face‐to‐face, online, written Theoretical basis: not reported Description of control: delayed intervention control, plus included bi‐annual BMI screening; health education; dental and nutrition screening
Outcomes	Outcomes relating to child dietary intake: not reported Outcomes relating to child physical measures: Annual change in BMI percentile, annual change in BMI z‐score Number of participants analysed: unclear Data collection measure: objectively measured (CDC) Data collector: health workers Validity of measures used: not reported Outcome relating to child language and cognitive performance: not reported Outcome relating to child social/emotional measures: not reported Outcome relating to child quality of life: not reported Outcome relating to cost: Total operation cost, time Number of participants analysed: not reported Data collection measure: not reported Data collector: not reported Validity of measures used: not reported Outcome relating to adverse consequences: not reported
Notes	Funding source: CDC Community Transformation Grant. Funding for the HAP pilot evaluation was provided by the Feeling Good Project, funded by USDA SNAP‐Ed.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	For each health worker, eligible ECEC centres were listed in alphabetical order. A list of the same length, of random, unique, unsorted numbers was generated using randomizer.org. For each health worker, ECEC centres had an equal chance of being assigned to 1 of 2 intervention groups.
Allocation concealment (selection bias)	Low risk	Baseline data collected before cluster randomisation
Blinding of participants and personnel (performance bias) Physical outcomes	Low risk	The programme health workers and ECEC providers were not blinded to treatment allocation. However, the outcome is not likely to be influenced by lack of blinding.
Blinding of participants and personnel (performance bias) Cost	Unclear risk	The programme health workers and ECEC providers were not blinded to treatment allocation. It is unclear whether the outcome is likely to be influenced by lack of blinding.
Blinding of outcome assessment (detection bias) Physical outcomes	Low risk	No blinding of outcome assessors, however children's height and weight were measured using a standardised protocol and calibrated instruments, and are unlikely to be influenced by lack of blinding.
Blinding of outcome assessment (detection bias) Cost	Unclear risk	No blinding of outcome assessors. It is unclear whether the outcome is likely to be influenced by lack of blinding.
Incomplete outcome data (attrition bias) Physical outcomes	High risk	The number of ECEC centres and children included in the HAP evaluation analysis varied each year, depending on the availability of BMI change data (primary outcome). Study authors stated that "Due to lack of unique child identifiers across child care centres, the analysis did not track the BMI changes of the same children across years." As a result, the risk of bias was assessed as high.
Incomplete outcome data (attrition bias) Cost	Low risk	The outcome was collected as an average cost per service.
Selective reporting (reporting bias)	Unclear risk	No prospective trial protocol or trial registration so it was unclear whether there was selective outcome reporting.
Recruitment bias	Unclear risk	It is unclear whether individuals were recruited to the study before or after randomisation of clusters.
Baseline imbalance	Unclear risk	Children's income, race, ethnicity, and social determinants of health were unknown and not controlled for in the research design or analysis.
Loss of clusters	High risk	9 of the 19 centres in the intervention group did not receive the allocated intervention. 7 of the 24 centres in the control group did not receive the allocated intervention. Loss of 6 clusters in Year 1 and 9 clusters in Year 2
Incorrect analysis	Low risk	Study authors stated that "The Child Care Health Program + HAP vs. Child Care Health Program + HAP Delayed groups were compared in intention‐to‐treat analyses, which accounted for clustered data. Year‐specific hierarchical linear models used child‐level data to test for a main effect of time between the Autumn to Spring screenings."
Contamination	Unclear risk	No evidence to make assessment
Other bias	High risk	Study authors stated that "Many potentially confounding and/or effect modifying factors, including local, statewide, and National initiatives, were operating in the background during the HAP pilot evaluation period." (Detailed explanation in study.) Authors also stated that "Randomization may not have eliminated bias related to treatment assignment, due to the relatively small number of child care centres and uneven demographic distribution across child care centres. Randomisation would not have controlled for time‐varying factors that happened to correlate with HAP exposure, and independently predict changes in child BMI."