Many Studies Have Been Conducted on the Effects of Having

question 20

Multiple Choice

Many studies have been conducted on the effects of having a pet on the response to medical problems and on mental health. But doctors in Berlin were interested in the effects of having a pet bird on lung cancer. (I assume they were wondering if birds might cause air pollution that could lead to lung cancer.) They asked 239 patients with lung cancer and 429 controls without lung cancer whether they had a pet bird. Ninety eight of the 239 patients did have a bird, while 101 of the 429 controls had a bird. (That strikes me as a very high percentage of bird owners, but those are the data.)
Why would it be wrong to calculate relative risk in this study?

• A) The study is a retrospective study.
• B) Relative risk rarely tells us anything.
• C) Risk is not a meaningful concept in this study.
• D) both b and c

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Definitions:

Total Return

The overall financial gain or loss on an investment, including both capital appreciation/depreciation and income like dividends and interest over a given time period.

U.S. Dollars

The official currency of the United States, widely used as a global reserve currency and standard for international transactions.

International Stocks

Shares of companies based outside of an investor's home country, offering diversification benefits.

Portfolio Risk

The potential for loss due to the variability of returns from the various securities in a portfolio.