Yeh 2018a.

Methods	Study design: cluster‐randomized controlled trial Study grouping: parallel group Study aim: "... to determine the following: (1) the weight distribution of [preschoolers] in Head Start facilities in a Midwestern metropolitan area; (2) whether providing nutrition education with [African American preschoolers] and their [caregivers] could establish healthy eating habits, nutrition knowledge, and improve their weight status; and (3) whether replacing refined grain with whole grain products in all school meals could alter blood lipid levels" (quote) Study period: 2008‐2009 academic year Total number of arms: 3 Description of intervention arms: 1. Nutrition education for preschoolers and their caregivers (child + caregiver); 2. Nutrition education for preschoolers (child only); 3. No intervention control (not eligible) Number of clusters per arm: 2 Average cluster size: 33.83 children Sample size justification and outcome used: the sample size was determined based on previous publications regarding the number of students per study arm and by convenience sampling (unpublished information provided by the study authors) Unit of allocation: Head Start center Missing data handling: not reported Reported limitations: 1. Small sample size; 2. Intervention had modest intensity; 3. Did not collect dietary records to validate dietary changes; 4. May not have been adequately powered to detect change; 5. Some teachers or peers refused to try whole grain products in the meal, thereby reducing exposure through role modeling; 6. Children may not have had sufficient access to whole grain products at home; 7. Lack of co‐operation among some food service workers; 8. Short intervention period Randomization ratio and stratification: 1:1:1; stratification not reported Participant compensation or incentives: participants received US dollar (USD) 20 for completing the baseline questionnaire and USD 20 for completing the post‐intervention questionnaire. An additional USD 20 was provided to those who completed the blood sample
Participants	Baseline characteristics Child + caregiver arm (intervention group) Female (PROGRESS‐Plus): n (%): 22/54 (41) Age in years (PROGRESS‐Plus): not reported Race/ethnicity/language/culture (PROGRESS‐Plus): not reported Place of residence (PROGRESS‐Plus): not reported Caregiver education (PROGRESS‐Plus): not reported Religion (PROGRESS‐Plus): not reported Household income/socioeconomic status (PROGRESS‐Plus): not reported Social capital (PROGRESS‐Plus): not reported Caregiver work hours and other characteristics that may indicate disadvantage (PROGRESS‐Plus): not reported Disability (PROGRESS‐Plus): not reported Sexual orientation (PROGRESS‐Plus): not reported Child weight status: body mass index (BMI) percentile, mean (SD): 62.0 (31.0); prevalence overweight/obesity, n (%): 18 (33.4) Child diet: not reported Child physical activity: not reported Caregiver weight status: not reported Caregiver diet: not reported Caregiver physical activity: not reported Caregiver civil status (PROGRESS‐Plus): not reported Child‐only arm (control group) Female (PROGRESS‐Plus): n (%): 23/47 (49) Age in years (PROGRESS‐Plus): not reported Race/ethnicity/language/culture (PROGRESS‐Plus): not reported Place of residence (PROGRESS‐Plus): not reported Caregiver education (PROGRESS‐Plus): not reported Religion (PROGRESS‐Plus): not reported Household income/socioeconomic status (PROGRESS‐Plus): not reported Social capital (PROGRESS‐Plus): not reported Caregiver work hours and other characteristics that may indicate disadvantage (PROGRESS‐Plus): not reported Disability (PROGRESS‐Plus): not reported Sexual orientation (PROGRESS‐Plus): not reported Child weight status: BMI percentile, mean (SD): 67.8 (26.8); prevalence overweight/obesity, n (%): 16 (34.1) Child diet: not reported Child physical activity: not reported Caregiver weight status: not reported Caregiver diet: not reported Caregiver physical activity: not reported Caregiver civil status (PROGRESS‐Plus): not reported Recruitment methods: study investigators recruited parents during the schools' scheduled parent orientations. The study's goals, benefits and risks, confidentiality procedures, and incentive structure were explained, and parents were invited to consent to take part Inclusion criteria: cluster: participating Head Start program (additional information not provided); participant: child aged 3 to 5 years and a caregiver Exclusion criteria: not reported Age of participating children at baseline: 3 to 5 years (preschool) Total number randomized by relevant group: total across all study arms: n = 203; child + caregiver arm: n = 66, child‐only arm: n = 63. Study authors did not report how many children were enrolled in the randomized classes Baseline imbalances between relevant groups: at baseline, no significant differences were reported between study arms Total number analyzed by relevant group: BMI percentile (child + caregiver arm: n = 54, child‐only arm: n = 47) Attrition by relevant group: attrition rates were calculated as the number of children excluded from analysis divided by the number of children randomized based on unpublished information provided by the authors: child + caregiver arm: 18.2% (12/66); child‐only arm: 23.8% (15/63) Description of sample for baseline characteristics reported above: children with measurements at baseline and post‐test, that is, those included in analyses (child + caregiver arm: n = 54, child‐only arm: n = 47)
Interventions	Intervention characteristics Child + caregiver arm (intervention group) Brief name/description (TIDieR #1): Head Start−based nutrition program plus a caregiver nutrition education program Focus of intervention: diet Behavior change techniques: in addition to the child‐only intervention, the following techniques were applied separately or differently in the child + caregiver arm: "shaping knowledge," "natural consequences," "comparison of behavior," "repetition and substitution," "comparison of outcomes" Why: rationale, theory, or goal (TIDieR #2): caregivers play a central role in young children's diets and eating patterns. Study authors did not describe the use of theory in development of this intervention How, where, and when and how much (TIDieR #6 to 8): in addition to the child‐only intervention, this intervention consisted of 1‐hour nutrition education meetings every month. Classes were held at 2 Head Start centers at a time determined by the center director. The intervention lasted 7 months Who: providers (TIDieR #5): same as child‐only arm Economic variables and resources required for replication: not reported Strategies to address disadvantage: not reported Subgroups: change in BMI percentile was examined for all children and also for only overweight and obese children Assessment time points: baseline, 7 months (end of intervention) Co‐interventions: not reported What: materials and procedures (TIDieR #3 to 4): in addition to materials and procedures provided to the child‐only arm, caregivers were invited to attend nutrition classes. Topics were based primarily on participant request and included cooking demonstrations, recipe modifications to common foods to reduce fat content or increase fiber or whole grain content, food tastings, and providing information about children's nutritional needs to motivate caregivers to provide healthy foods. Each class consisted of a 20‐minute presentation followed by discussion and interactive activities. The instructor also prepared a healthy recipe based on the caregivers’ input Tailoring (TIDieR #9): the content of the nutrition education classes was based mostly on participants' requests and interests as reported at baseline Modifications (TIDieR #10): not reported How well: planned and actual (TIDieR #11 to 12): not reported Sensitivity analyses: not reported Child‐only arm (control group) Brief name/description (TIDieR #1): Head Start−based nutrition program Focus of intervention: diet Behavior change techniques: "shaping knowledge," "comparison of outcomes," "antecedents" Why: rationale, theory, or goal (TIDieR #2): establishment of healthy eating habits begins early in life and is an important factor in prevention of obesity. African American children are at elevated risk of obesity. Study authors did not describe the use of theory in development of this intervention How, where, and when and how much (TIDieR #6 to 8): food service providers substituted whole grain products for products made with white flour. Nutrition classes are offered twice a week for 30 minutes each for the duration of the school year. The intervention lasted 7 months Who: providers (TIDieR #5): dietetic interns under the supervision of a registered dietitian taught the nutrition education classes. Food service providers were trained by the research staff to implement the food service changes Economic variables and resources required for replication: not reported Strategies to address disadvantage: not reported Subgroups: change in BMI percentile was examined for all children and also for only overweight and obese children Assessment time points: baseline, 7 months (end of intervention) Co‐interventions: not reported What: materials and procedures (TIDieR #3 to 4): nutrition education sessions included introductions to "body building" foods, discussion of food groups, and fresh fruit and vegetable taste tests. Fruit‐ and vegetable‐shaped hand puppets were used to introduce the content. In addition, refined grain products were replaced with whole grain products in school meals, and food service providers were encouraged to follow the USDA Head Start menu and recommended recipes and cooking methods Tailoring (TIDieR #9): not reported Modifications (TIDieR #10): not reported How well: planned and actual (TIDieR #11 to 12): not reported Sensitivity analyses: not reported
Outcomes	The following instruments were used to measure outcomes relevant to this review at baseline and at 7 months (end of intervention) Children's dietary intake: Dietary Risk Assessment (DRA) survey to assess daily intake from different food groups; study authors reported this instrument to be validated Data from the end‐of‐intervention assessment were not reported in a usable format and could not be retrieved from the study authors Children's anthropometry: height measured with a Seca 214 portable stadiometer (Seca North America East, Hanover, Maryland, USA) and weight measured with Tanita Model BC551 portable digital scale (Tanita Corp of America, Arlington Heights, Illinois, USA) Data for BMI percentile were calculated using the Centers for Disease Control and Prevention calculator and are available for the end‐of‐intervention assessment. Although the prevalence of overweight or obesity was calculated, data were not reported for the end‐of‐intervention assessment and could not be retrieved from the study authors
Identification	Study name: Healthy Kids Healthy Lives (HKHL) Country: USA Setting: United Children and Family Head Start programs in Detroit, Michigan Types of reports: published journal article and Masters thesis Comments: used the following reports: (1) Akil 2013, and (2) Yeh 2018b, as well as unpublished information provided by the study authors (Yeh 2018c [pers comm]). For discrepancies between reports, we sought clarification from the study authors Author's name: Yulyu Yeh Email: yyeh@tamu.edu Conflicts of interest: "the authors declare that they have no conflict of interest" (quote) Sponsorship source: Office of the Vice President for Research, Wayne University
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation	Low risk	Judgment comment: school names were placed in a bag, and the research co‐ordinator drew names (Yeh 2018c [pers comm])
Allocation concealment	Unclear risk	Judgment comment: methods used to conceal the allocation sequence were not described
Blinding of participants and personnel All outcomes	Low risk	Judgment comment: no information on blinding of participants and personnel was provided. However, given the nature of the intervention, there would have been no way to blind participants and personnel. Also, the children were aged 3 to 5 years, so their performance was not likely to have been influenced by lack of blinding
Blinding of outcome assessment All outcomes	Unclear risk	Judgment comment: no information on blinding of outcome assessors was provided. Height and weight were measured. Therefore, body mass index (BMI) may or may not have been influenced by lack of blinding
Incomplete outcome data All outcomes	High risk	Judgment comment: we calculated attrition rates as the number of children excluded from analysis divided by the number of children randomized, based on unpublished information provided by the study authors. Total attrition was 19.2% (39/203) for the study overall and 20.9% (27/129) for the 2 relevant study arms. Differential attrition for the 2 relevant study arms was 5.6% (12/66 vs 15/63) (Yeh 2018c [pers comm])
Selective reporting	High risk	Judgment comment: the trial was not registered and no protocol was cited that could be retrieved. Anthropometric data were reported in a format that could be entered into meta‐analysis, but dietary outcomes were not reported in a usable format, and we could not retrieve these data from the study authors
Recruitment bias	High risk	Judgment comment: randomization was carried out before participant recruitment (Yeh 2018c [pers comm])
Baseline imbalance	Unclear risk	Judgment comment: study authors noted that, at baseline, "there was no difference in BMI among the three groups" (Yeh 2018b, p 555). They did not report on similarities and differences between clusters
Loss of clusters	Low risk	Judgment comment: no clusters were lost (Yeh 2018c [pers comm])
Incorrect analysis	High risk	Judgment comment: study authors did not report adjusting for clustering in the analysis and did not report intraclass correlation coefficients (ICCs)
Comparability with individually randomized trials	Unclear risk	Judgment comment: information provided was insufficient to permit judgment
Other sources of bias	Low risk	Judgment comment: we detected no other sources of bias

ABC: Activity Begins in Childhood.

ANCOVA: analysis of covariance.

BMI: body mass index.

CATCH: Child and Adolescent Trial for Cardiovascular Health.

CDC: Centers for Disease Control and Prevention.

CIHR: Canadian Institutes for Health Research.

DILQ: Day in the Life Questionnaire.

FV: fruits and vegetables.

ICC: intracluster correlation coefficient.

IPAQ: International Physical Activity Questionnaire.

LPA: light physical activity.

MANCOVA: multi‐variate analysis of covariance.

MVPA: moderate to vigorous physical activity.

PAQ‐C: Physical Activity Questionnaire for Older Children.

PE: physical education.

PROGRESS‐Plus: place of residence, race/ethnicity/culture/language, occupation, gender/sex, religion, education, socioeconomic status, social capital, personal characteristics associated with discrimination, features of relationships, and time‐dependent relationships.

RAPA: Rapid Assessment of Physical Activity questionnaire.

RCT: randomized controlled trial.

SD: standard deviation.

SES: socioeconomic status.

SSB: sugar‐sweetened beverage.

TIDieR: Template for Intervention Description and Replication.