Similarity between Cross sectional study design and Ecological study design:-: (A) Both studies are done at a point of time, (B) Both provide prevalence, (C) Both are based on primary data, (D) Unit of study is population
Answer is A. Cross Sectional Study Ecological Study Both studies are done at a point of time - Done based on primary Data i.e. collected by Investigation himself from House to House. - It provides "Prevalence", so a/K/a Prevalence Study - a/K/a "SNAPSHOT Study". - Done based on Secondary Data i.e. Collected data from records of hospital Data is not collected by Investigator himself. - Used in Nutritional Surveys - Cannot calculate strength of association / prevalence - Unit of Study is population and results are extrapolated projected not on Individuals but on total population. This drawback is known as "Ecological Fallacy".