Natural history of a disease is studied with
Longitudinal studies are in which observations are repeated in the same population over a prolonged period of time by means of follow-up examination. They are useful in1) to study the natural history of the disease and its future outcome2) for identifying risk factors for disease3) For finding out incidence rate or rate of occurrence of new cases of a disease in the community.Park 23e pg: 70
Longitudinal studies
Cross sectional studies
Randomized control trials
Randomized sampling
Epidemiology