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
Kaplan meier methods is used for - 
Select and explain. 
A. Survival, B. Prevalance, C. Incidence, D. Frequency
A: Survival
Answer: A: Survival 
Explanation: Ans. is 'a' i.e., Survival o The Kaplan-Meier estimator (also known as the product limit estimator) estimates the survival function from life-time data. In medical research, it might be used to measure the fraction of patients living for a ceain amount of time after treatment. o A plot of the Kaplan-Meier estimate of the survival function is a series of horizontal steps of declining magnitude which, when a large enough sample is taken, approaches the true survival function for that population. The value of the survival function between successive distinct sampled observations is assumed to be constant. o An impoant advantages of the Kaplan-Meier curve is that the method can take into account "censored" data ? losses from the sample before the final outcome is observed (for instance, if a patient withdraws from a study).