Marya 1981.

Methods	Randomised controlled trial
Participants	Hindu women
Interventions	Women were randomised throughout the 3rd trimester pregnancy to 1 of the following groups: ‐ Group 1: 600,000 IU vitamin D2 orally in both the 7th and 8th months of pregnancy (n = 20); ‐ Group 2: 1200 IU vitamin D (with 375 mg calcium, as tablets) per day (n = 25). Type of setting was not specified; India, exact location was not specified. Health worker cadre was not described.
Outcomes	Infant Birthweight Laboratory method used for assessment of vitamin D concentrations: not available
Notes	• Start of supplementation: during the third trimester (both 7th and 8th months of pregnancy) • Pre‐gestational BMI (kg/m2): unknown/mixed • Supplementation scheme/regimen: single doses in both the 7th and 8th months of pregnancy versus daily doses (comparison) • Skin pigmentation based on Fitzpatrick skin tone chart (Fitzpatrick 1988): not specified • Latitude: India (location not specified) • Season at the start of pregnancy: not specified Source of funding: not declared Dates of the study: not declared Declarations of interest among primary researchers: not reported
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Insufficient information about how randomisation was done.
Allocation concealment (selection bias)	Unclear risk	Insufficient information to determine whether allocation concealment was done and how.
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Insufficient information to allow judgment.
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Insufficient information to permit. judgment.
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	Insufficient information to permit. judgment.
Selective reporting (reporting bias)	Unclear risk	Insufficient information to permit judgment.
Other bias	Unclear risk	Insufficient information to permit judgment.