Pilz 2016.

Study characteristics
Methods	Randomised clinical trial with parallel‐group design (2 groups)
Participants	36 participants (25% women), aged 18 to 75 years, mean age 61 years, with liver cirrhosis Inclusion criteria: compensated cirrhosis, 25‐hydroxyvitamin D < 30 ng/mL, aged 18 to 75 years, and a negative pregnancy test in women of childbearing potential Exclusion criteria: presence of hepatocellular carcinoma, hypercalcaemia (plasma calcium concentrations > 2.65 mmol/L), pregnant or lactating women, drug intake as part of another clinical study, estimated glomerular filtration rate according to Modification of Diet in Renal Disease formula < 15 mL/min/1.73 m2, any clinically significant acute disease requiring drug treatment, regular intake (in addition to study medication) of vitamin D > 800 IU daily during the last 4 weeks before study entry
Interventions	Intervention: vitamin D3 2800 IU/day (Oleovit D3, Fresenius Kabi, Austria) (n = 18) Control: placebo daily (n = 18) For 8 weeks
Outcomes	Primary outcome: vitamin D status Secondary outcomes: liver function tests (i.e. AST, ALT, gamma glutamyl transpeptidase, and alkaline phosphatase), albumin, international normalised ratio, bilirubin, and hyaluronic acid; and parameters of mineral metabolism (i.e. parathyroid hormone, total plasma calcium, free plasma calcium, urinary midstream calcium to creatinine ratio, and plasma phosphate)
Stated aim of study	To evaluate the effects of vitamin D supplementation on 25‐hydroxyvitamin D, parameters of liver function and synthesis, and hyaluronic acid as a marker of liver fibrosis
Notes	“No patient died during the study and there was no excess of adverse events in the vitamin D group.” Study sponsored by the Medical University of Graz, Austria.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Sequence generation performed using computer random number generation.
Allocation concealment (selection bias)	Low risk	Participant allocations could not have been foreseen in advance of, or during, enrolment. Central and independent randomisation unit controlled allocation. Investigators were unaware of allocation sequence.
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Blinding of participants and key study personnel ensured, and it is unlikely that blinding could have been broken.
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Blinding of outcome assessment ensured, and it is unlikely that blinding could have been broken.
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.
Other bias	Unclear risk	Trial may or may not have been free of other factors that could put it at risk of bias, such as small‐trial bias.