Janssen 2010.

Methods	Randomised, double‐blind, placebo‐controlled trial using parallel group design (2 intervention groups)
Participants	Number of participants randomised: 70 geriatric women older than 65 years with serum 25 hydroxyvitamin D concentrations between 20 and 50 nmol/L Inclusion criteria: vitamin D‐insufficient geriatric women able to walk and follow simple instructions. Exclusion criteria: treatment with vitamin D or steroids in the previous 6 months, a history of hypercalcaemia or renal stones, liver cirrhosis, serum creatinine > 200 μmol/L, malabsorptive bowel syndrome, primary hyperparathyroidism, uncontrolled thyroid disease, anticonvulsant drug therapy, and/or presence of any other condition that would probably interfere with the participants' compliance (i.e., surgery planned).
Interventions	Participants were randomly assigned to receive: Intervention group: vitamin D₃ (400 IU) plus calcium (500 mg) daily (n = 36) Comparator group: placebo vitamin D₃ plus calcium (500 mg) daily (n = 34), for a 6‐months period.
Outcomes	Outcomes reported in abstract of publication Primary outcomes: muscle strength, power and functional mobility. Secondary outcomes: none defined.
Stated aim of study	Quote from the publication: "To test the hypothesis that vitamin D plus calcium supplementation improves muscle strength and mobility, compared with calcium monotherapy in vitamin D insufficient female geriatric patients."
Notes	"This study was financially supported by the Prevention Program (Project 96070602) of ZonMw, The Netherlands." Additional information on funding of the trial received through personal communication with Dr Henie C.J.P. Janssen (06.02.2014)
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote from the publication: "Randomization was done in blocks of six, to minimize any seasonal influence between the treatment groups." Comment: sequence generation was achieved using computer random number generation.
Allocation concealment (selection bias)	Low risk	Quote from the publication: "Trial medication was provided by an independent hospital pharmacist who also performed the randomization." Comment: allocation was controlled by a central and independent randomisation unit.
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Quote from the publication: "No person involved, i.e., subjects, investigators, or physicians who treated the subjects, had access to the randomization procedure." Comment: the trial was described as blinded, the parties that were blinded, and the method of blinding was described, so that knowledge of allocation was adequately prevented during the trial..
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Quote from the publication: "No person involved, i.e., subjects, investigators, or physicians who treated the subjects, had access to the randomization procedure." Comment: the outcome measurement is not likely to be influenced by lack of blinding.
Incomplete outcome data (attrition bias)	Low risk	Quote from the publication: "Eleven subjects withdrew from the trial: death (1), cognitive decline (4), a malignant lung tumor (1), recurrent upper urinary tract infections with malaise (2), acute emotional distress (1), hip fracture (1) and peritonitis (1)." Comment: the underlying reasons for missing data are unlikely to make treatment effects depart from plausible values.
Selective reporting (reporting bias)	Low risk	Comment: predefined, or clinically relevant and reasonably expected outcomes were reported.
For‐profit bias	High risk	Comment: the trial was sponsored by the industry.
Other bias	Low risk	Comment: the trial appears to be free of other components that could put it at risk of bias .