Question

In: Statistics and Probability

A researcher wanted to determine if the incidence of influenza was more frequent in Caucasian or...

A researcher wanted to determine if the incidence of influenza was more frequent in Caucasian or Hispanic populations. He decided to investigate by accessing Emergency Room records at a local hospital. He found influenza was 2x times more frequent in Hispanics than in Caucasians. What could be the possible bias associated with the study and how did it influence the findings of the study? (5 points)

Describe in detail how would you conduct the above study so that selection bias does not occur?

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Expert Solution

A researcher wanted to determine if the incidence of influenza was more frequent in Caucasian or Hispanic populations. He decided to investigate by accessing Emergency Room records at a local hospital. He found influenza was 2x times more frequent in Hispanics than in Caucasians. What could be the possible bias associated with the study and how did it influence the findings of the study? (5 points)

The selection bias is associated with this study. May be more number of Hispanics attend the Emergency Room than the Caucasians. This leads to selection bias.

Describe in detail how would you conduct the above study so that selection bias does not occur?

Selection bias arises when the study population is not a random selection from the target population for which a statement is to be made. In this case we have to stratify the Emergency Room records by Hispanics and Caucasians. Select cases proportion to the corresponding strata sizes. This will reduce the selection bias.


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