Lorvand Amiri 2016.

Methods	Randomised clinical trial with parallel group design (3 groups).
Participants	120 participants (38% women), aged 18 to 65 years, mean age 41 years, with NAFLD. Inclusion criteria: BMI 25 kg/m2 to 35 kg/m2, serum 25‐hydroxyvitamin D3 level < 15 ng/mL, reporting a daily calcium intake 700 mg/day to 800 mg/day, and willingness to introduce a dietary change to lose weight. Exclusion criteria: calcium intake < 700 mg/day or > 800 mg/day (in diet or as a supplement); drugs for blood glucose or lipid control; pregnancy or having given birth in the past year or planning a pregnancy in the next 6 months; lactation; weight loss ≥ 10% of body weight within the 6 months before enrolment; participation in competitive sport; abnormal thyroid hormone concentration; intake of medications that could affect body weight or energy expenditure (or both); allergy; smoking; diagnosis of chronic diseases including inflammatory diseases; heart, liver, and renal failure; cancer; acute myocardial infarction; diabetes; stroke; or serious injuries and any other conditions that were not suitable for the trial as evaluated by the physician.
Interventions	Intervention 1: vitamin D 25 μg/day as calcitriol (Jalinus Arya Co., Iran) + calcium carbonate placebo (25 mg/day as lactose; Jalinus Arya Co, Iran) (n = 37). Intervention 2: vitamin D 25 μg/day as calcitriol (Jalinus Arya Co., Iran) + calcium (500 mg/day as calcium carbonate; Jalinus Arya Co., Iran) (n = 37). Control: placebo of calcitriol + placebo of calcium (25 mg/day as lactose; Jalinus Arya Co., Iran) (n = 36). After lunch with a glass of water for 12 weeks.
Outcomes	Primary outcomes: weight loss, body fat, fasting plasma glucose, serum insulin concentrations, lipid profiles, and liver function tests. Secondary outcomes: carbohydrate and lipid metabolism.
Stated aim of study	To compare effect of vitamin D supplementation with and without calcium on anthropometric measures and biochemical parameters in people with NAFLD during a weight‐loss programme.
Notes	Clinical trial registered at Iranian Registry of Clinical Trials (www.irct.ir) IRCT registration number: IRCT201408312709N29. Trial did not receive any specific grant from funding agencies in the public, commercial, or not‐for‐profit sectors. Additional information received through personal communication with authors on 20 January 2017.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Participants randomly assigned using computer‐generated random‐numbers method by project co‐ordinator.
Allocation concealment (selection bias)	Low risk	Participant allocations could not have been foreseen in advance of, or during, enrolment. Allocation controlled by a central and independent randomisation unit.
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Products administered by blinded research assistant to blinded participants. Shape, colour, and packaging of placebo similar to supplements in the intervention group.
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Insufficient information to assess whether missing data in combination with method used to handle missing data were likely to induce bias.
Incomplete outcome data (attrition bias) All outcomes	Low risk	Missing data were unlikely to make treatment effects depart from plausible values.
Selective reporting (reporting bias)	Low risk	All predefined outcomes reported fully.
For‐profit bias	Unclear risk	Trial may or may not have been free of for‐profit bias as no information provided on clinical trial support or sponsorship.
Other bias	Unclear risk	Trial may or may not have been free of other factors that could put it at risk of bias.