Following is true about longitudinal studies: (A) Used to study the natural history of the disease, (B) Single outcome, (C) Are economical, (D) Are efficient
Answer is A. Longitudinal studies are useful in: To study the natural history of disease and it's future outcome For identifying risk factors of disease For finding out incidence rate or rate of occurrence of new cases of disease in the community Ref: 25th edition, Park's Textbook of Preventive and Social Medicine, Page no. 78