Shapses 2001.

Study characteristics
Methods	Randomised, controlled, parallel‐group trial (2 groups) Duration of study: not specified Duration of follow‐up: 6 months
Participants	Setting characteristic: participants were in a moderate weight‐loss programme Inclusion criteria: obese healthy women; stable weight for ≥ 3 months before the start of the study Exclusion: pregnant or lactating within the previous year; history of an irregular menstrual cycle; ill or taking medication known to interfere with bone metabolism, including oral contraceptives Age: 42.1 (SD 6.2) years Sample: Total included 60 Calcium group (weight loss): 14 (baseline) and 14 (6 months) Placebo group (weight loss): 14 (baseline) and 14 (6 months) Placebo group (maintain stable weight): not specified (baseline) and 10 (6 months) Country: USA
Interventions	Intervention group: calcium citrate 1000 mg Control group: placebo tablets (gift from Mission Pharmaceuticals, San Antonio, Texas, USA) Other intervention: reduced calorie diet was then individually created using the American Diabetic Association Exchange List. Administration: daily Duration of treatment: 6 months
Outcomes	BMD: lumbar and total body BMC: lumbar and total body Biomarkers: pyridinoline, deoxypyridinoline, N‐telopeptide, osteocalcin, parathyroid hormone, and 25‐hydroxyvitamin D Intake: energy, protein, fat, carbohydrates, calcium, phosphorus, vitamin D, and magnesium.
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 analysis of the placebo group showed substantial deviations from the randomised intervention.
Selective reporting (reporting bias)	High risk	The groups assigned initially from the methodology, during the study were arbitrarily reassigned.
Other bias	Unclear risk	The final allocation did not coincide with the baseline allocation of participants.