Which of the following is used for selecting patients with respect to potential factors that will affect the results?
Systematic random sampling
Simple random sampling
Stratified random sampling
Cluster sampling
Ans: C. Stratified random samplingRef. Park 24/e p886, 23/e p850, 22/e p792; BK Malunan 6th/100-101).Stratified random sampling is used for selecting patients with respect to potential factors that will affect the results.Stratified random sample:The sample is deliberately drawn in a systematic way so that each poion of the sample represents corresponding strata of universe.This method is paicularly useful where one is interested in analyzing the data by a ceain characteristic of population, viz. Hindus, Christians, Muslims, age-groups etc.