Blomkvist 2021.

Study characteristics
Methods	Study design: cluster‐RCT Length of follow‐up from baseline: 3 months Unit of allocation: kindergartens Unit of analysis: child
Participants	Service type: kindergarten Operation: public and private Country (region): Norway ((Telemark, Oppland, Sør‐Trøndelag and Møre og Romsdal) Country income classification: high Low‐SES sample: unclear Population description: the 4 counties covered 2 different geographical areas of Norway and included public and private kindergartens located in both rural and urban settings. Inclusion criteria: having children of the appropriate age (i.e. born in 2016) Exclusion criteria: kindergartens registered as ‘open kindergartens’ in which children and their parents attend together (n = 18), kindergartens registered with < 4 children (n = 7) and kindergartens with children from 3‐5 years only (n = 12) were not invited. Number of services randomised: 46 kindergartens (16 intervention 1, 15 intervention 2, 15 control) Number of children randomised: 267 children (111 intervention 1, 85 intervention 2, 71 control) Characteristics Children Age: 16.7 months (SD 3.0) Gender (% female): 47.60% Ethnicity: all children were born in Norway Parents Age (years): 30.9 (SD 5.4) Gender (% female): 88.70% Ethnicity: Mother born in Norway: 91.5% Father born in Norway: 89.5% Parent/family SES: Mothers' education, high: 64% Fathers' education, high: 42.1% Method of recruitment: the invitations were sent to the kindergarten managers by email and included detailed information about the study and a link to the study registration web page. The kindergarten managers received 1 reminder email after a couple of weeks. As few kindergartens (n = 32) registered for the study initially, a random selection of kindergarten managers (n = 321) was additionally contacted by telephone and asked if they had received the email and further asked if they could be interested in participating in the study. The phone call recruitment lasted until the number of kindergartens registered was assumed to yield the planned study sample size. Missing data/dropout: total loss to follow‐up: 102/246 = 41% Reasons for dropout: 21 parents registered for the trial but did not complete the baseline questionnaire, leaving 246 children. 3 of the kindergartens (n = 29 children) withdrew consent shortly after randomisation (2 of them due to sick leaves and pregnancies amongst the staff and 1 kindergarten withdrew due to economic issues). 73 parents (34%) did not complete the post‐intervention questionnaire, leaving 144 children for the main analysis. Characteristics of dropouts: mothers without a higher education were more likely to drop out of the study. Amongst the complete cases, there were slightly fewer fathers with a higher education in Intervention 1, and a slightly higher baseline intake of intervention vegetables amongst children in Intervention 2.
Interventions	Programme name: Barns matmot 2.0 Number of conditions: 2 interventions, 1 control Intervention duration: 12 weeks Intervention setting: ECEC Intervention strategies: Intervention 1 (Menu moderation and sensory lessons) Health curriculum Children Education: kindergarten staff were instructed to implement pedagogical tools including weekly sensory lessons for the participating children. Ethos and environment Children Exposure: during the sensory lessons, children were introduced to the intervention vegetable of the month, presented in 3 different ways; in the first week, it was presented raw, in the second week, raw with a dip and in the third week, it was presented differently (e.g. baked or otherwise prepared) (3 additional exposures of each food compared to Intervention 2). Children were served a warm lunch meal with alternating vegetables for 3 d/week during the 3‐month intervention period. Role modelling/healthy eating practices: kindergarten staff were given advice on meal practice and feeding practices during mealtime and encouraged to sit down with the children and eat the same food during lunchtime. Service Resources: the kindergartens had access to the 3 menus with 9 different recipes in a password‐protected website designed specifically for each intervention group. Each of the 3 menus had 1 vegetable in focus: spinach, celeriac and fennel. Recommendations for meal and feeding practices were also presented in short informational videos on the study website. Kindergartens were offered compensation to buy necessary kitchenware, such as a good knife, saucepans or a hand blender. Support: if the kindergarten personnel had questions during the intervention, they could email or telephone a contact person using information on the website. Families Resources: the parents of the registered children were also given access to the website with the 9 recipes; however, the parents had no commitments or tasks regarding introducing the menus at home. Recommendations for meal and feeding practices were also presented in short informational videos on the study website. Intervention 2 (Menu moderation) Ethos and environment Children Exposure: children were served a warm lunch meal with alternating vegetables for 3 d/week during the 3‐month intervention period. Service Resources: the kindergartens had access to the 3 menus with 9 different recipes in a password‐protected website designed specifically for each intervention group. Each of the 3 menus had one vegetable in focus: spinach, celeriac and fennel. Kindergartens were offered a compensation to buy necessary kitchenware, such as a good knife, saucepans or a hand blender. Support: if the kindergarten personnel had questions during the intervention, they could email or telephone a contact person using information on the website. Families Resources: the parents of the registered children were also given access to the website with the 9 recipes; however, the parents had no commitments or tasks regarding introducing the menus at home. Intensity of intervention: Intervention 1: children were exposed to 3 d/week for 3 months; staff implemented weekly sensory lessons in the classroom. Intervention 2: children were exposed to alternating vegetables for 3 d/week for 3 months. Intervention delivered by: Intervention 1: ECEC staff Intervention 2: ECEC staff Modality: Intervention 1: face‐to‐face, online, written Intervention 2: online, written Theoretical basis: not reported Description of control: Usual care
Outcomes	Outcomes relating to child dietary intake: Vegetable intake, intervention vegetables intake Number of participants analysed: Intervention 1 baseline: 103 Intervention 1 follow‐up: 63 Intervention 2 baseline: 78 Intervention 2 follow‐up: 42 Control baseline: 65 Control follow‐up: 39 Data collection measure: selected items from FFQ Data collector: parent Validity of measures used: not reported Outcomes relating to child physical measures: 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: not reported Outcome relating to adverse consequences: not reported
Notes	Funding source: this research project was funded by the Norwegian Women’s Public Health Association, and some projects costs were funded by the University of Agder and the Teacher’s Education Unit at the University of Agder. Approximately one‐fifth of the wages cost for the corresponding author was funded by the Hospital of Southern Norway.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Study authors stated that "The random allocation sequence was generated in SPSS by the last author, who had neither contact with the kindergartens nor access to or information from the completed questionnaires."
Allocation concealment (selection bias)	Low risk	Study authors stated that "The 46 kindergartens included were randomised into one of three groups after the parents had completed the baseline questionnaire, approximately 2 weeks before the start of the intervention."
Blinding of participants and personnel (performance bias) Diet outcomes	High risk	Study authors stated that "The first author contacted the kindergarten managers to inform them about which group they were randomised to." Blinding of staff not reported, though staff in the intervention groups had access to resources indicating blinding may have been broken and the outcome is likely to be influenced by lack of blinding.
Blinding of outcome assessment (detection bias) Diet outcomes	High risk	Study authors stated that "The first author contacted the kindergarten managers to inform them about which group they were randomised to." Parents completed the food frequency questionnaire. Blinding of parents not reported, though parents in the intervention groups had access to resources indicating blinding may have been broken. The outcome measurement is likely to be influenced by lack of blinding.
Incomplete outcome data (attrition bias) Diet outcomes	High risk	Study authors stated that "In total, 267 children were registered for the study. Twenty‐one parents registered for the trial but did not complete the baseline questionnaire, leaving 246 children. Three of the kindergartens (n = 29 children) withdrew consent shortly after randomisation (two of them due to sick leaves and pregnancies amongst the staff and one kindergarten withdrew due to economic issues). Seventy‐three parents (34%) did not complete the post‐intervention questionnaire, leaving 144 children for the main analysis (total loss to follow‐up: 102/246 = 41%)." A full intention‐to‐treat analysis could not be performed. Due to the magnitude of missing data, the risk of bias was assessed as high.
Selective reporting (reporting bias)	Low risk	Additional measures, including anthropometric data of children, were also collected according to the protocol, however the authors stated that "Only primary outcomes of the intervention are included in the present paper."
Recruitment bias	Low risk	All participants and kindergartens were recruited prior to randomisation.
Baseline imbalance	Low risk	Study authors stated that "The cluster randomisation produced groups that were broadly comparable at baseline." It is reported that there were slightly fewer fathers with a higher education in intervention 1, and a slightly higher baseline intake of intervention vegetables amongst children in intervention 2, based on case completers. The authors used adjusted models to control for these variables.
Loss of clusters	Low risk	Loss of 3 clusters, however reasons were unrelated to the intervention and comprised a small percentage of all clusters. Study authors stated that "Three of the kindergartens (n = 29 children) withdrew consent shortly after randomisation (two of them due to sick leaves and pregnancies amongst the staff and one kindergarten withdrew due to economic issues)."
Incorrect analysis	Unclear risk	Adjusting for clusters was not reported, however the authors stated that "To address any imbalances that may have resulted from the cluster design and losses to follow‐up, we also present a set of adjusted effect estimates, controlling for the baseline values of each outcome, and maternal and paternal education." There is not enough information to assess whether an important risk of bias exists.
Contamination	Unclear risk	No evidence to make assessment
Other bias	Low risk	No clear other source of bias