Tammela 1993.

Methods	A double‐blind, placebo‐controlled randomized trial of men with bladder outlet obstruction due to BPH.
Participants	Geographic region: Finland Study setting: NA N = 36 (finasteride n = 19; placebo n = 17) Baseline symptom score: NA Baseline peak urine flow: finasteride = 7.7 mL/s; placebo = 8.8 mL/s Baseline prostate volume: finasteride = 50 cc; placebo = 48 cc Baseline PSA: finasteride = 5.4 ng/mL; placebo = 4.0 ng/mL Mean age (range): 65.0 years (54 to 80) Race: NA Inclusion: ambulatory; good general physical and mental health with moderate‐to‐severe symptoms urinary obstruction; enlarged prostate gland; peak urine flow < 15 mL/s documented by two physiological free flow uroflowmetry measurements whole voiding at least 150 mL; a urodynamic pattern of bladder outlet obstruction Exclusion: definitive diagnosis of chronic bacterial prostatitis; history of urethral strictures; presence of urinary tract infection; previous prostate or testicular surgery; evidence of prostate cancer by digital exam; PSA > 40 ng/mL; prostate biopsies were taken in patients with PSA > 10 ng/mL before they were excepted into the trial; patients with residual urine volume of > 350 mL and those had catheterization for acute urinary retention were excluded; chronic concurrent use of barbiturates, heparin, warfarin, theophyllamine, antiarrhythmic agents and drugs with antiandrogenic properties were not allowed; patients with a serum creatinine of > 1.5 mg/dL of liver function tests outside the normal range were excluded Study discontinuations: n = 0 Study duration: 6 months
Interventions	Finasteride 5 mg once daily Placebo
Outcomes	Peak urine flow Post‐void residual volume Adverse effects
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	no description
Allocation concealment (selection bias)	Unclear risk	no description
Blinding (performance bias and detection bias) All outcomes	Low risk	"double‐blind" but no description
Incomplete outcome data (attrition bias) All outcomes	Low risk	yes
Selective reporting (reporting bias)	Low risk	yes
Other bias	Low risk	yes
Intention‐to‐treat analysis	Unclear risk	unclear
Non‐industry funded	High risk	no description