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Chapter 4: Q 48. (page 253)

Cell phones and brain cancer One study of cell phones and the risk of brain cancer looked at a group of 469 people who have brain cancer. The investigators matched each cancer patient with a person of the same age, gender, and race who did not have brain cancer, then asked about the use of cell phones. Result: 鈥淥ur data suggest that the use of handheld cellular phones is not associated with risk of brain cancer.鈥�

(a) Is this an observational study or an experiment? Justify your answer.

(b) Based on this study, would you conclude that cell phones do not increase the risk of brain cancer? Why or why not?

Short Answer

Expert verified

Part (a) Observational study.

Part (b) No.

Step by step solution

01

Part (a) Step 1: Given information

We must evaluate whether this is an observational or an experimental study.

02

Part (a) Step 2: Concept

Observational research looks at people and assesses factors of interest without trying to affect their responses.

03

Part (a) Step 3: Explanation

This was an observational study in which an observer analysis was used to collect information regarding the concept results of treatment for participants who were randomly allocated to a treated or control group. The researchers haven't decided whether or not participants should use cell phones in this study.

04

Part (b) Step 1: Explanation

Nonetheless, because this is an observational study, the intent and effect cannot be deduced, this analysis cannot say that cell phones do not increase the risk of brain cancer.

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