In the year 2000, an investigator drew a 1% simple random sample of all adults in a community of 100,000 residents (i.e. the total sample of the study is 1% of 100,000). An initial examination revealed 100 existing cases of a chronic disease D for which there is no recovery. Prevalent cases were excluded from the study. 200 people included in the cohort had an exposure E prior start of the study (hint: the rest were unexposed). Within the next 5 years, 100 new cases of the disease D occurred in this fixed study population, and half of these new cases (100/2) were exposed (hint: the other half were unexposed cases). | | D+ | D- | Total | |---|---|---|---| | E+ | | | 200 | | E- | | | | | Total | | | | Estimate the relative risk (RR) of developing a disease D in exposed group compared to the risk of developing a disease D in unexposed group. Show calculations for credit.
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- **Simple Random Sample**: A sample in which each member of the population has an equal chance of being selected. - **Prevalent Cases**: Existing cases of a disease at the start of the study. - **Incident Cases**: New cases of a disease that develop during the Show more…
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