Awasthi 2013 (Cluster)

Methods	Cluster‐RCT Method to adjust for clustering: cluster used as unit of analysis ('means of block‐specific numbers of deaths per AWC') Cluster unit: a block of 10,000 to 20,000 children Average cluster size: 9259 approximately (under‐5 population 1 million/108 clusters). ICCs: not reported Length of follow‐up: 5 years
Participants	All children living in endemic area Number analysed for primary outcome: total population of 1 million children at any one time, with a total of 2 million children ever in the trial Age range: 1 to 6 years Inclusion criteria: all preschool children then aged 1 to 6.0 years in 72 participating blocks near Lucknow that were considered to have a well‐functioning ICDS system with willing district and block directors and with paid workers in most of the block's anganwadi centres Exclusion criteria: severe anaemia (haemoglobin < 75 g/L)
Interventions	Multiple doses vs placebo Factorial design in four arms: Usual care – no placebo; 6‐monthly vitamin A [for 5 years]; 6‐monthly 400 mg albendazole; Both 6‐monthly vitamin A and 6‐monthly 400 mg albendazole.
Outcomes	Mortality Not included in review: A subset of 5165 children were assessed for other outcomes (height, weight, BMI, haemoglobin, prevalence of illness in past 4 weeks)
Notes	Location: Lucknow, India Community category: 3 Annually about 30 non‐randomly selected preschool children were surveyed for growth, nutritional and morbidity outcomes from one randomly selected AWC per block (10,000 to 20,000 children in about 120 AWCs per block). Source of funding: UK Medical Research Council, USAID OMNI project, World  Bank. Albendazole (Zentel) was donated by SmithKlineBeecham.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	"randomly allocated"; "Randomisation (in Oxford) was stratified in groups of 4 neighbouring blocks, where possible in the same district."
Allocation concealment (selection bias)	Unclear risk	See above.
Blinding (performance bias and detection bias) All outcomes	Unclear risk	All cause mortality is the outcome.
Incomplete outcome data (attrition bias) All outcomes	Low risk	89 AWCs (2%) in the albendazole block lost to follow‐up, 86 AWCs (2%) in the placebo block lost to follow‐up. "Loss to follow‐up is defined by having only 1‐6 follow‐up visits (mean only 3, as against 12 in the included AWCs), and was generally because the AWC had ceased to function." Inclusion of all randomized participants (number evaluable/number randomized): Denominator for mortality was all children. A subset of 5165 non‐randomly selected children were assessed for other outcomes.
Selective reporting (reporting bias)	Low risk	Mortality is the single outcome for this trial.
Other bias	Low risk	Recruitment bias: unclear Baseline imbalance: unclear Loss of clusters: unclear Incorrect analysis: Cluster adjusted (low risk) Comparability with RCTs randomizing individuals: unclear