Characteristics of studies not included in the individual participant data meta-analysis.

aComparison group, based on information reported by the authors; for study 31 there was no comparison with non-hormonal-contraceptive users, so the comparison group is women using NET-EN.
b“Injectable” reported if this was the term used by the authors and the specific progestin was not mentioned; all effect sizes rounded to one decimal place.
IRR, incidence rate ratio; NA, not applicable; NR, not reported; OR, odds ratio; RR, risk ratio.
Characteristics of studies not included in the individual participant data meta-analysis.