Measuring the quality and duration of contraceptive use: an overview of new approaches.

This paper provides an overview of recently developed approaches to the measurement of contraceptive continuation and failure rates, using retrospective survey data rather than the data from clinical trials or program statistics which are more traditionally used. The approaches fall into 2 categories, 1 relying on retrospective contraceptive histories and the other on current status information. The 1st section of the paper discusses the need for new methodologies; conventional applications using clinic and acceptor data are described, some recent results from developed countries presented, and their limitations illustrated. In the 2nd section, each new approach is presented in terms of its data requirements, methods of calculation, and empirical applications. Finally, potential sources of bias and the ability of the approaches to accommodate them are discussed.