TABLE 1.

Characteristics of the search strategy according to the PICOT framework

Population	Parents experiencing socio‐economic disadvantage (during pregnancy or the first 2 years of the child life), i.e.: those identified with low socio‐economic position (e.g. measured by education, occupation, or income); those eligible for Special Supplemental Nutrition Program for Women's, Infants, and Children (WIC), Early Head Start programs, or Medicaid (USA); those experiencing psycho‐social risks (e.g. teen pregnancy, single motherhood, depression) or housing difficulties; or those living in disadvantaged areas.
Intervention	Interventions had to be delivered in the first 1,000 days (herein defined as pregnancy and the first two years of the child) with the aim of improving one or more of the outcomes described below. Interventions could be directed at individual behavior change (e.g. individual counselling, audio‐visual materials, social support) or include structural components (e.g. incentives, vouchers, food stamps, coupons to facilitate healthy behaviors; and referral to social and health support services in the community).
Comparison	Intervention studies had to include a control group, i.e. a group of parents/infants who were not exposed to the intervention or who received ‘usual care’.
Outcome(s)	Studies had to address one or more of the following outcomes in children: ‐ Parental feeding practices, such as breastfeeding (BF) a and age at complementary feeding; ‐ Eating behaviors, dietary intake; ‐ Physical activity and movement measures, such as outdoor play and tummy time; ‐ Sedentary behaviors, such as screen time, TV viewing, and time spent restrained; ‐ Sleepb; ‐ Anthropometric or growth measures, such as weight, height, body mass index (BMI), OW, OB, percent body fat, skin fold thickness, weight gain velocityc.
Timeframe for follow‐up	Childhood: at least one of the eligible outcomes had to be assessed for effectiveness beyond the childbirth.

^a BF should however not be the only focus/outcome of the intervention; ^bSleep should however not be the only focus/outcome of the intervention;

^c Anthropometrics at birth should however not be the only outcome(s) assessed.