Comparison 1. Calcium versus placebo.

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1.1 Total hip bone mineral density (BMD)	3	174	Mean Difference (IV, Random, 95% CI)	‐0.04 [‐0.11, 0.03]
1.1.1 Total hip BMD	3	174	Mean Difference (IV, Random, 95% CI)	‐0.04 [‐0.11, 0.03]
1.2 Lumbar spine BMD	4	202	Mean Difference (IV, Random, 95% CI)	0.00 [‐0.06, 0.06]
1.2.1 Lumbar spine BMD	4	202	Mean Difference (IV, Random, 95% CI)	0.00 [‐0.06, 0.06]
1.3 Withdrawals for any reason	4	261	Risk Ratio (M‐H, Fixed, 95% CI)	0.78 [0.52, 1.16]