HSS 3101 Lecture Notes - Lecture 32: Prevalence, Selection Bias, Odds Ratio
24 Nov 2018
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Document Summary
Weaknesses: exposure and outcome, useful to describe the, very limited potential measured at same point in prevalence of disease to establish causal time, fast, inexpensive effects, subjects with and without. Hypothesis: selection bias outcome are compared generating, survival bias. Cross-sectional studies can be thought of as providing a snapshot" of the frequency and characteristics of an outcome at a particular point in time. In a cross-sectional study, a certain outcome and an exposure status in a specified population are measured simultaneously. It is usually not possible to distinguish whether the exposure preceded or followed the outcome, Cause and effect relationships are not certain. Point prevalence is a measure of the proportion of people in a population who have a disease or condition at a particular time, such as a particular date. It is like a snapshot of the disease in time.
