Taneja 2010.

Methods	RCT Sample size: 2482 Inclusion criteria: children aged 6–30 months Exclusion criteria: children from families intending to move out of the study area, requiring hospitalisation on the day of enrolment, having received vitamin A within the previous 2 months, or who refused to participate
Participants	Children Age: 6–30 months Country: India Setting: an urban slum of Dakshinpuri in New Delhi, India (15,000 dwellings and 75,000 inhabitants)
Interventions	Type: supplementation of vitamin A and zinc At enrolment, all children also received a single dose of vitamin A (104.7 μmol for infants and 209.4 μmol for older children). Weight and length were measured at enrolment and 4 months later. Weekly visits were conducted by field workers to ascertain morbidity in the previous 7 days. Change in length, weight, LFA z‐scores, and weight‐for‐length z‐scores after 4 months of supplementation were assessed. Urban specificity: none Level of factors tackled: individual Duration (years): 0.3 Delivery: weekly visits by field workers at the participants house Comparison: IG: daily zinc supplementation administered at home CG: daily placebo supplementation administered at home Measurement: weight and length were measured at enrolment and 4 months later. Morbidity was measured every 7th day. PROGRESS at baseline: none
Outcomes	WFA, LFA/HFA, WFH, diarrhoea
Notes	No effect in any of the subgroups defined for age, income, gender, zinc levels in the crude analysis nor after adjusting for age, gender, income, breastfeeding status, and baseline anthropometric status. No funding information Impact of the intervention: IG: mean change: LFA –0.14, SD 0.44; 0.12 cm less (95% CI –0.02 to 0.26) CG: mean change: LFA –0.12, SD 0.43; 3.55 cm change in length
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Randomisation scheme (in blocks of 8) generated off‐site by a statistician at Statens Serum Institute, Copenhagen, Denmark, who was not otherwise involved with the study, using SAS software (version 8.1; SAS Institute).
Allocation concealment (selection bias)	Unclear risk	Eligible children were individually allocated to zinc or placebo groups.
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Zinc and placebo syrups were similar in appearance, taste, and packaging; and were prepared, packaged, and labelled with a unique identification number according to the randomisation scheme by GK Pharma Aps, Koge, Denmark in unbreakable bottles. The supplies for each child (6 bottles, 1 for each month and 2 extra in case of loss) were packed in a labelled plastic bag before the commencement of the study.
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Randomisation was by a person in Denmark not related to the study. Preparation of the syrups (zinc or placebo) was done before the commencement of the study and each child's supplies were packed in a labelled plastic bag using a unique identification number according to the randomisation scheme. The zinc and placebo syrups bottles were identical in appearance.
Incomplete outcome data (attrition bias) All outcomes	Low risk	Measurements could not be obtained in 51 children who refused participation after enrolment, 184 who left the study area before completion of follow‐up, and 3 who died.
Selective reporting (reporting bias)	Unclear risk	No published protocol to establish this risk, but all outcomes described in methods were reported.
Other bias	Unclear risk	Unclear if the participants benefited from other ongoing interventions during the study period.
Similarity of outcome measures at baseline	Low risk	Performance or patient outcomes were measured prior to the intervention, and there were no important differences across study groups (only maternal nutrition outcomes were measured).
Similarity of baseline characteristics	Low risk	Baseline characteristics of the study and control providers were reported and similar in both groups.
Protection against contamination	Low risk	Allocation was done randomly and it was unlikely that the CG received the intervention. Supplementation was administered at home by mothers.

BSC: bovine serum concentrate; CG: control group; HFA: height‐for‐age; IEC: information, education, and communication; IG: intervention group; LBW: low birth weight; LFA: length‐for‐age; LNS: lipid‐based nutrient supplement; MMN: micronutrient mineral; MSPP: Ministry of Public Health and Population; MUAC: mid‐upper‐arm circumference; RCT: randomised controlled trial; RDA: recommended daily allowance; SAM: severe acute malnourished; SD: standard deviation; SES: socioeconomic status; WFA: weight‐for‐age; WFH: weight‐for‐height; WPC: whey protein concentrate.