Intra-Uterine Contraception: Recommended Procedures for Data Analysis

Abstract

This paper presents procedures for the computation of net cumulative event and closure rates based on all (for IUD use). It is submitted as a contribution to comparable data analysis in the field. Events which occur after the cutoff date are to be ignored; time for tabulation of data should be about 2 months after cutoff date to allow for late reports of events which occurred before this date: statistical analysis should be by periods of use or segments ended by an event such as expulsion removal or accidental pregnancy. Release from follow-up and loss to follow-up are closures by definition. Tables illustrate recommended methods of computation. These provide for use in clinical studies with attendance at scheduled intervals but can be modified for use in field studies based on home interviews with selected women who at some previous time had been fitted with an IUD.