This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Social & Preventive Medicine
Contraceptive efficacy is measured by 
Select and explain. 
A. Pearl Index and Life table analysis, B. Pearl Index only, C. Life table analysis and Couple protection rate, D. Pearl Index and Couple protection rate
A: Pearl Index and Life table analysis
Answer: A: Pearl Index and Life table analysis 
Explanation: Contraceptive Efficacy: Is assessed by measuring the number of unplanned pregnancies that occur during a specified period of exposure and use of a contraceptive method. Two methods used are:

Pearl Index
Life table analysis

Life Table Analysis (LTA) as measure of contraceptive efficacy:
– LTA calculates a failure rate per month of use
– Better measure than PI