Contraception efficacy is measured by
Pearl index only
Pearl index and life table analysis
Life table analysis and couple protection rate
Couple protection rate and pearl index
Two methods that have been used to measure contraceptive efficacy are the Pearl index and life-table analysis.Pearl index is defined as the number of " failures per 100 woman-years of exposure (HWY)"Failure rate per HWY = Total accidental pregnancies / Total months of exposure x 1200The Pearl index is usually based on a specific exposure (usually one year) and, therefore fails to accurately compare methods at various durations of exposure.The life-table analysis calculates a failure rate for each month of use. A cumulative failure rate can then compare methods for any specific length of exposure.Park 23e pg: 510
Demography and family planning