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What is Best index for measuring contraceptive efficacy is and explain in detail?
Life table analysis : Calculates a failure rate for each month of use Cumulative failure rate can then compare methods of any specific length of exposure Women who leave a study for any reason other than unintended pregnancy are removed from analysis, contributing their exposure until the time of exit Reference : Park&;s textbook of preventive and social medicine, 23rd edition, Page no: 510