Rourke 1998.

Study characteristics
Methods	Randomised, controlled, parallel‐group trial (2 groups) Duration of study: not specified Duration of follow‐up: 1 year
Participants	Setting characteristic: athletes Included: healthy women, athletes from collegiate teams Excluded: screened athletes denied the use of steroids, anticonvulsants, or tobacco Age: 18–22 years Calcium: 19.9 (SD 0.2) years Placebo: 19.2 (SD 0.3) years Sample: Total included 30 Calcium group: 17 (baseline), 17 (6 months), and 17 (12 months) Placebo group: 13 (baseline), 13 (6 months), and 13 (12 months) Country: USA
Interventions	Calcium versus placebo Intervention group: elemental calcium supplementation 1000 mg Control group: placebo Administration: daily Duration of treatment: 1 year
Outcomes	BMD: lumbar spine (L1–L4), total hip, femoral neck, trochanter, wards triangle, and radius. Anthropometric measures: height, weight, BMI, % body fat, VO2max.
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Not specified.
Allocation concealment (selection bias)	Unclear risk	Not specified.
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Not specified.
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Not specified.
Incomplete outcome data (attrition bias) All outcomes	High risk	The reasons for the loss of 33% of the participants were not explained. The study began with 45 participants and finished with 30 participants. The study authors presented only the analysis per protocol (calcium group 17 participants and placebo group 13 participants).
Selective reporting (reporting bias)	Unclear risk	Not specified.
Other bias	High risk	Problems with adherence to treatment. "Compliance data suggest that the CS [calcium] group failed to consume the prescribed 1000 mg daily intake of calcium. Furthermore, subjects in the placebo group reported a higher intake of calcium when compared with the CS group."