Module 1

 Questions when creating a study:

1. Outcome of interest?
2. Groups?
3. Population?
4. Type of Study?

Comparative studies are intended to show differences of an outcome between two or more groups.

    Cross Sectional - Collected at one point in time
    Longitudinal - multiple data sets collected at different points in time

    Retrospective - Collecting "group data" on selected outcomes
    Prospective - Collecting "outcome" on selected groups

Cohort studies gather data on groups of interest

Study Design	Pros	Cons
Randomized trials	Strength of evidence	May be unethical
Cohort studies	Relative risk	Bias confounding
Case-Control studies	Easy and inexpensive	Bias confounding
Cross-sectional	Simplest	Weakest evidence