POPM 3240 Lecture Notes - Lecture 6: Cohort Study, Rare Disease, Observational Study

• School: University of Guelph
• Department: Population Medicine
• Course: POPM 3240
• Professor: Matthew Little

Document Summary

Observational study observation in natural environment, do not actually intervene or change a(cid:374)(cid:455)thi(cid:374)g that is goi(cid:374)g o(cid:374) i(cid:374) the (cid:272)ourse of a perso(cid:374) or a(cid:374)i(cid:373)al(cid:859)s life. Main types of observational studies: cross-sectional studies, cohort studies, case control studies. Examples of descriptive studies include: case reports describe rare condition/unusual case(s) Often biased sampling methods: case series describe usual clinical course of a condition of interest by combining observations from a series of patients with the outcome of interest. Sample size often too small to determine if exposure is associated with the outcome (even if we do have exposure and outcome status for each individual) Often biased sampling methods: surveys collect various information from individuals in a population with no comparison group. May not be collecting exposure and outcome information (cannot run statistical tests to determine if they are associated with one another)