Methods	Design: RCT
	Unit of randomisation: Individually randomised trial
Participants	Location/Setting: State run school in Pune, India
	Sample size: 50 adolescent girls
	Dropouts/withdrawals: 1 out of 50 loss to follow‐up
	Sex: Only adolescent post menarchal girls
	Mean age: 14.6 years
	Inclusion criteria: Post Menarche adolescent girls
	Exclusion criteria: Not specified
Interventions	Intervention (sample size):
	Group 1 (N = 25): Subjects in the treatment group were administered 6 vitamin D2 (Ergocalciferol; Celltech, UK) tablets each containing 1.25 mg
	(50,000 IU) orally at 1, 4, 7 and 10 months
	Control (sample size):
	Group 2 (N = 25): Placebo group the local pharmacist prepared tablets which were identical in number, colour, size and texture to the ergocalciferol, but contained only sucrose
	The intervention was provided for a duration of one year and all participants received 250 mg elemental calcium (calcium carbonate) daily
Outcomes	Primary outcomes: Total body bone mineral content, Lumbar spine bone mineral content and lumbar spine bone mineral apparent density
	Secondary outcomes: Total body lean, fat mass and serum concentrations of biochemical parameters
	Timing of outcome assessment: After one year of intervention
Notes	Study start date: February 2006
	Study end date: April 2007
	Funding source: Not specified
	Conflicts of interest: None declared