Session 8: Case-Control Studies Flashcards
Balanced Odds
When the selection odds equals 1. Under this situation, the case control OR will equal the OR in the underlying cohort study
Case-Control Study
A comparison of the exposure experience of cases and controls. Best understood as a condensed version of a cohort study (real or imagine) in which study subjects are selected according to their disease (or other outcome) status
Coherence
In the context of a case-control study, when controls come from the source population that generated the cases.
Efficiency
Able to produce the same results using fewer resources. A case-control study is generally more efficient than a cohort study when the outcome is rare or has a long latency period
Nested Case-Control Study
A case-control study developed within a defined cohort from which both cases and controls are selected; drawn from a primary study base
Non-nested Case-Control Study
A case-control study that is not developed within a defined cohort; drawn from a secondary study base
Primary Study Base
When membership in the source population cane be enumerated or directly identified
Secondary Study Base
When we begin with a roster of cases and try to reconstruct the source population (underlying cohort) from which they arose
Selection Odds
The ratio of the odds of being selected into the case control study from the underlying source population for exposed and unexposed cases compared with exposed and unexposed controls
Source Population
The exposed and unexposed individuals who give rise to the cases in the study
Traditional Case-Control Study
A case-control study where controls are selected at the end of the study period
Well Controls
A control group in which people with disorders other than the disease under study are excluded from the controls but not the cases. Violates a key principle of control selection: selection criteria for controls should be identical to selection criteria for cases
