Question

Power lines and cancer 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 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 association 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 prove that living near power lines doesn’t cause cancer? Explain your answer.

Short answer

a. The above mentioned in an observational study.

b. No, this study doesn't prove prove that living near power lines doesn’t cause cancer.

Step-by-step solution

Given Information

Scientists compared $638$children who had leukemia with $620$who had not.

No association between exposure to magnetic field and leukemia was found.

Whether study is observational or experimental

Experimental Study is one in which certain people in group is applied treatment and other portion is not.

In observational study, without affecting people, members of sample are surveyed.

Here, afterwards, measurements are done. It's a observational study.

If study prove living near power lines does not cause cancer

Study should be experimental to prove cause and effect as variables are controlled that effect the result.

Hence, this study doesn't prove prove that living near power lines doesn’t cause cancer.