Quiz 1, Module Case-control
1. Based on the information you gathered, which of the following hypotheses is the most appropriate for your case-control study?
- (1) Those who consumed EnduroBrick are more likely to be diagnosed with Susser Syndrome than those who did not; (2) Those who consumed Quench-It are more likely to be diagnosed with Susser Syndrome than those who did not consume Quench-It.
- Individuals diagnosed with Susser Syndrome are more likely to have been members of the Superfit Fitness Center than individuals without Susser Syndrome.
- Individuals diagnosed with Susser Syndrome are likely to be exposed to a variety of different exposures than are individuals not diagnosed with Susser Syndrome
Answer (a) —
correct:
These hypotheses clearly state the expected causal factors (EnduroBrock and Quench-it), and the expected direction of effect. They are sufficiently explicit to allow the hypotheses to be tested after collecting data. In addition, we know that, although a case-control methodology selects individuals based on disease status and compares the exposure distribution between cases and controls, a properly conducted case-control design can compare the disease experience of the exposed to the disease experience of the unexposed.
Answer (b) —
incorrect:
This hypothesis is not specific enough. Affiliation with the Superfit Fitness Center is associated with many different factors. A study hypothesis should clearly define exposures and outcomes.
Answer (c) —
incorrect:
This hypothesis does not state a potentially causal link between exposures and outcome, and is not specific enough to allow for collected data to support or refute it.
