Statistical Analysis
Descriptive statistics were reported as frequency (%) for categorical variables. We implemented a disproportionality analysis to evaluate the correlation between the queried drugs and the ADR of priapism. Reporting odds ratio (ROR) and the 95% confidence intervals (CI) were calculated according to Stricker and Tijssen. ROR is a homolog to the odds ratio for case-control studies and corresponds to the exposure odds among cases of priapism over the odds of exposure among non-cases: ROR = (a/b) × (c/d); a: drug and ADR of interest, b: drug of interest with other ADRs, c: other drugs with ADR of interest, and d: other drugs and ADRs.
For a drug of interest, cases (a) were considered the reports of “priapism” according to MedDRA, while non-cases (b) were all other ADR reports during the same period. The analysis was then stratified for the age groups of the consumers. An ROR was considered significant if the number of drug-ADR combinations was three or more. Statistical analysis was performed using Stata 13 (StataCorp, TX, USA). The design and reporting of the study followed the STROBE guidelines and checklist for observational studies (see appendix).