All of the following studies are 'analytical', except:: (A) Field trials, (B) Coho studies, (C) Case control studies, (D) Ecological studies
Answer is A. Field trial is a type of experimental or interventional study. Coho study, case control study and ecological study are all types of analytical studies. Ref: Park's Textbook of Preventive and Social Medicine, By K. Park, 19th Edition, Page 58