Experimental studies are meant to -: (A) Test etiological hypothesis, (B) Find out prevalence rates, (C) Find out cause of epidemics, (D) To find out the history of disease
Answer is A. Experimental studies involve an active attempt to change a disease determinant or the progress of a disease and are similar in design to experiments in other sciences. The major experimental design is randomized control trials. Field trials and community trials are other experimental studies. (refer pgno:63 park 23 rd edition)