2. Type and dosage of supplementation of calcium and vitamin D.
| Author | Type of intervention/dosage | Type of administration | Follow‐up |
| Calcium compared to placebo | |||
| Barger‐Lux 2005 | Calcium carbonate 1500 mg | 3 capsules of 500 mg with each meal | 36 monthsa |
| Rourke 1998 | Calcium elemental 1000 mg | 1 tablet a day | 12 months |
| Shapses 2001 | Calcium citrate 1000 mg | 1 tablet a day | 6 months |
| Winters‐Stone 2004 | Calcium carbonate 1000 mg | 2 chewable tablets a day | 12 months |
| Vitamin D compared to placebo | |||
| Islam 2010 | Vitamin D3 10 μg (400 IU) | 1 tablet a day | 12 months |
| Andersen 2008 | Vitamin D3 10 μg (400 IU) or 20 μg (800 IU) | 1 tablet a day | 12 months |
| Calcium + vitamin D compared to placebo | |||
| Woo 2007 | Calcium 1000 mg + vitamin D3 5 μg (200 IU) | 2 sachets per day | 24 months |
| Islam 2010 | Vitamin D3 10 μg (400 IU) + calcium lactate 600 mg | 1 tablet a day | 12 months |
aOnly the first 12 months period of this study were included in the analysis.