Q. 25 - The Practice of Statistics for AP

Question

Power lines and cancer $(4.2,4.3)$ Does living near power lines cause leukemia in children? The

National Cancer Institute spent 5 years and $\$5$ million gathering data on this question. The researchers compared $638$ children who had leukemia with$620$ who did not. They went into the homes and actually measured the magnetic fields in children's bedrooms, in other rooms, and at the front door. They recorded facts about power lines near the family home and also near the mother's residence when she was pregnant. Result: no connection between leukemia and exposure to magnetic fields of the kind produced by power lines was found.

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

(b) Does this study show that living near power lines doesn't cause cancer? Explain.

Step-by-Step Solution

Answer

a) Observational study

b) No

Part (a) Step 1: Given Information

Is it true that children who live near power lines develop leukemia?

Part (a) Step 2: Explanation

Individuals are subjected to a treatment on purpose in order to study their reactions in an experiment.

Observational research aims to collect data without interfering with the observed scene.

Observational studies

Due to the fact that the measurements were not obtained till later.

Part (b) Step 1:Given Information

Is it true that children who live near power lines develop leukemia?

Part (b) Step 2: Explanation

To prove a cause-and-effect link, we need an experiment rather than observational research.

Because an experiment allows us to control a large number of variables that may have an impact on the research's outcomes but aren't included in the study (these other variables not included in the study could be the true cause in an observational study).