Gokce 2012.

Study characteristics
Methods	Study design: Randomized controlled trial Masking: single‐blind Number of arms: 2
Participants	Inclusion criteria: 30–70‐year‐old male patients, normal libido, IIEF< 17, no previous use of PDE5 Is and normal serum testosterone levels 300 ng/dL Exclusion criteria: history of any pelvic surgery, having any kind of medication for ED, having any neurological or mental problem, liver or hepatic insufficiency, use of nitrates, and use of antiandrogens Baseline characteristics Atorvastatin 10 mg/day n:45 were randomized and 41 were measured sex: male age: 57.1 Total cholesterol: 195.1 mg/dL (5.04 mmol/L) LDL cholesterol: 127.3 mg/dL (3.29 mmol/L) HDL cholesterol: 42.2 mg/dL (1.09 mmol/L) Triglycerides: 155.6 mg/dL (1.76 mmol/L) Total testosterone: 323.4 ng/dL (11.21 nmol/L) No treatment n:45 were randomized and 39 were measured sex: male age: 55.8 Total cholesterol: 189.4 mg/dL (4.90 mmol/L) LDL cholesterol: 128.4 mg/dL (3.32 mmol/L) HDL cholesterol: 40.9 mg/dL (1.06 mmol/L) Triglycerides: 149.0 mg/dL (1.68 mmol/L) Total testosterone: 330.7 ng/dL (11.47 nmol/L)
Interventions	10 mg/day atorvastatin for 3 months no treatment for 3 months
Outcomes	Total testosterone (3 months)
Statistical analysis and reporting	Sample size estimation was performed by a conventional statistical program by taking into account an effect size of 50% improvement in symptoms, andminimum number of patients needed to reject the null hypothesis was 120. For randomisation, NCSS program was used, and patients were blinded for the treatment. The statistical analysis was performed by SPSS ver. 15.0. (SPSS Inc.,Chicago, Illinois). Data are expressed as numbers and percentages for discrete variables and as means ± SD for continuous variables. The chi‐square analysis or Fisher’s exact test was used to assess the significance of differences between dichotomous variables. Continuous variables were compared by Student’s t‐test or Mann–Whitney U‐test.
Number of participants lost to follow‐up	Atorvastatin group: one lost to follow up and three discontinued; Of the three that discontinued; one was due to nausea and two was due to lack of efficacy No treatment group: two lost to follow up and four discontinued; Of the four that discontinued; one was due to headache and three was due to lack of efficacy
Source of funding	not reported
Notes	Location: Department of Urology, Ankara University School of Medicine, Adnan Saygun Caddesi, Altındag˘, Ankara, Turkey Department of Cardiology, Ankara University School of Medicine, Adnan Saygun Caddesi, Altındag˘, Ankara, Turkey
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Randomization, NCSS program was used
Allocation concealment (selection bias)	Unclear risk	Method of concealment is not described
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Objective outcome like serum total testosterone is not likely to be influenced by lack of blinding
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Testosterone was measured in a laboratory and the outcome measurement was not likely to be influenced by lack of blinding
Blinding of outcome assessment (detection bias): WDAEs	High risk	No blinding of outcome assessment, and the outcome measurement was likely to be influenced by lack of blinding
Selective reporting (reporting bias)	Unclear risk	No protocol was found and there is insufficient information to judge if it is low or high risk of bias
Selective reporting (reporting bias) WDAEs	Low risk	WDAE outcome reported
Source of funding, sponsorship and conflict of interest	Unclear risk	No source of funding reported
Incomplete outcome data (attrition bias): Total testosterone	Unclear risk	(4/45)*100 = 8.9% were not included in the testosterone measurement for the atorvastatin group (6/45)*100 = 13.3% were not included in the testosterone measurement for the control group