In the article “Height and Weight at Various Ages and Risk of Breast Cancer” (Annals of Epidemiology, Vol. 2, pp. 597–609), L. Brinton and C. Swanson discussed the relationship between height and breast cancer. The study, sponsored by the National Cancer Institute, took 5 years and involved more than 1500 women with breast cancer and 2000 women without breast cancer; it revealed a trend between height and breast cancer: “._______._______. taller women have a 50 to 80 percent greater risk of getting breast cancer than women who are closer to 5 feet tall.” Christine Swanson, a nutritionist who was involved with the study, added, “._______._______. height may be associated with the culprit,_______._______._______. but no one really knows” the exact relationship between height and the risk of breast cancer.
a. Classify this study as either an observational study or a designed experiment. Explain your answer.
b. Interpret the statement made by Christine Swanson in light of your answer to part (a).