This document classifies epidemiological studies into two main categories: observational studies and experimental studies. Observational studies are further divided into descriptive studies and analytical studies such as ecological, cross-sectional, case-control and cohort studies. Experimental studies, also known as intervention studies, involve randomized controlled trials, field trials and community trials.

1. Classification of epidemiological study
Presented by:- Gauri Shankar Saini
Mbbs

2. Classification
1. Observational studies:-
• Descriptive studies
• Analytical studies
a. Ecological
b.cross sectional
c. Case control
d. Cohort
2. Experimental studies intervention studies

3. Cont.
2. Experimental studies intervention studies
a. Randomised controlled trials
b. Field trials
c. Community trials