Ghaderi 2019.

Study characteristics
Methods	Study design: Randomized controlled trial Study grouping: Parallel group How were participants recruited: Study participants were approached at the psychiatry clinic Type of RCT: Randomized, double‐blind, placebo‐controlled trial
Participants	Baseline characteristics Vitamin D + probiotic supplements Sex (N, % female, % male): female 2 (7%), male 28 (93%) Age (mean, SD): 44.8 (SD 8.3) years Number of participants: 30 Placebo Sex (N, % female, % male): female 2 (7%), male 28 (93%) Age (mean, SD): 43.2 (SD 6.0) years Number of participants: 30 Overall Sex (N, % female, % male): female 4 (7%), male 56 (93%) Age (range): 25 to 65 years Number of participants: 60 Inclusion criteria: Any participant diagnosed with schizophrenia using DSM‐IV‐TR criteria with disease duration of at least two years, PANSS score of 55 or greater, treated with chlorpromazine (300 to 1000 mg/day, except clozapine) and agents anticholinergic (Trihexyphenidyl, 4 to 8 mg/day) during the last 6 months and aged 25 to 65 years old were included in the study. Exclusion criteria: Any participant with mental retardation (Intelligent Quotient of < 70), substance or alcohol addiction (except caffeine or nicotine) within the last 6 months of screening,a score of ≥14 on a 17‐item Hamilton Depression Rating Scale or a score of ≥ 4 on PANSS (depression item), anyone under treatment with lithium, carbamazepine, sodium valproic acid, with existing chronic and acute medical illness, with lactation or pregnancy, the use of antidepressants including MAO, TCA, SSRI in the last 6 months were excluded from this trials. Pretreatment: There was no significant difference between the two arms in terms of height, age, weight and BMI at baseline
Interventions	Intervention characteristics Vitamin D + probiotic supplements Class of drug: vitamin D and Probiotic supplements Dose: 50,000 IU of vitamin D3 plus 8 × 10^9 CFU of probiotic supplements (containing Lactobacillus acidophilus, Bifidobacterium bifidum, Lactobacillus reuteri, and Lactobacillus fermentum (each 2 × 109^)) Frequency: Vitamin D3 every 2 weeks and probiotic supplements every day Duration: 12 weeks Who delivered the intervention? Patient Type of intervention: Pharmacological Placebo Class of drug: Placebo which were capsules in the similar shape andpackaging as vitamin D and probiotic Dose: ‐ Frequency: ‐ Duration: 12 weeks Who delivered the intervention? Patient Type of intervention: Control
Outcomes	Fasting plasma glucose Outcome type: Continuous Reporting: Fully reported Unit of measure: mg/dl Direction: Lower is better Data value: Endpoint BMI Outcome type: Continuous Cholesterol (Total cholesterol) Outcome type: Continuous Reporting: Fully reported Unit of measure: mg/dl Data value: Endpoint Drop‐outs Outcome type: Dichotomous Reporting: Fully reported Direction: Lower is better Data value: Endpoint
Identification	Sponsorship source: The research grant provided by Research Deputy of Kashan University ofMedical Sciences (KAUMS). Country: Iran Setting: Psychiatry clinic Comments: ‐ Authors name: Zatollah Asemi Institution: 8 Research Center for Biochemistry and Nutrition in Metabolic Diseases, Kashan University of Medical Sciences Email: asemi_r@yahoo.com Address: Research Center for Biochemistry and Nutrition in Metabolic Diseases, Kashan University of Medical Sciences, Kashan, I.R, Iran
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote: "Computer‐generated random numbers were used by an instructed staff to randomize study participants at the psychiatry clinic".
Allocation concealment (selection bias)	Unclear risk	Judgement comment: not clearly mentioned
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Quote: "placebo which were capsules in the similar shape and packaging as vitamin D and probiotic" Judgement comment: No reference to how blinding was done or who provided the medication. The only mention to blinding is that the study is "double‐blind"
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Judgement comment: No information provided
Incomplete outcome data (attrition bias) All outcomes	Low risk	Judgement comment: The study addresses all of the primary outcomes prespecified in the Methods section and in trial that is registered. The drop‐outs were included with the reasons addressed. The drop‐out numbers (N = 4 of each group) is minimal and for similar reasons. The study includes all participants in the analysis, including those that dropped out, using intention‐to‐treat methods.
Selective reporting (reporting bias)	Unclear risk	Judgement comment: trial was retrospectively registered.
Other sources of bias	Low risk	Quote: "The research grant provided by Research Deputy of Kashan University of Medical Sciences (KAUMS)." Judgement comment: we did not find any other source of bias