A person wants to study a disease &;x&; and fat consumption. He obtained data for number of people affected with &;x&; from the government and the details of fat consumption from food industry. Type of study is: (A) Ecological study, (B) Cross sectional study, (C) Pesiological study, (D) Experimental study
Answer is A. Ecological (correlations) study. Unit of study is population (results not applicable to individuals). Done in a small time frame. It is inferior to coho and case control. Reference: Park's textbook of preventive and social medicine,K.Park,21st edition,page no:59 & 22nd edition, pg no.60.