| Methods |
Randomized controlled trial with blinding of the outcome assessor. Randomization by random numbers. The use of allocation concealment and blinding of the participants was not reported.
High number of exclusions after randomization. |
| Participants |
59 participants aged 25 to 51 years in an outpatient setting in Denmark. The inclusion and exclusion criteria were not stated. |
| Interventions |
Vasectomy (vas excision with both ends tied combined with fascial interposition) with irrigation of the distal vas with 40 ml of sterile water versus vasectomy without irrigation. |
| Outcomes |
The primary outcome measure was number of ejaculations to azoospermia. Other outcome measures were time to azoospermia, adverse events and procedure time. Medians and interquartile ranges were reported, so no data were available for analysis in this review. |
| Notes |
The report provides an a priori hypothesis and a sample size calculation. Due to the long‐time lapse from operation to azoospermia, 59 men were operated on before the necessary 30 men had fulfilled the test for azoospermia.
Analysis not according to intention‐to‐threat principle. |
| Risk of bias |
| Bias |
Authors' judgement |
Support for judgement |
| Allocation concealment (selection bias) |
Unclear risk |
no information |
