Summary of methodological issues
| Scientific/study design issue | Statistical concern | Solution(s) |
| Current versus total duration | Censoring status | ▶Current duration—ignore censoring ▶Total duration—infer censoring from questionnaire or follow-up |
| Fixed window sampling | Left truncation (length-biased sampling) | ▶Design study with longer sampling window ▶Restrict analysis to partnerships initiated within the sampling window, or ▶Use Kaplan–Meier estimate modified to account for left truncation ▶Randomly sample partnerships within a long window |
| Fixed number of partners sampling | Sample of partnerships biased towards individuals with fewer partners; possible length-biased sample | ▶Weight partnerships by total number of partners in lifetime ▶Randomly sample partnerships within a long window |
| Multiple partnerships per individual | Correlated data | ▶Use bootstrap or robust variance to compute CIs |