Failure rate of contraceptive method is determined by
Two methods have been used to measure contraceptive efficacy: 1. Pearl index and 2. Life table analysis Pearl index is defined as the number of failure rates per 100 woman years of exposure Reference : Park&;s textbook of preventive and social medicine, 23rd edition, Page no: 510
Pearl index
Half life
Number of accidental pregnancies
Period of contraceptive practice continued
Demography and family planning