Uncontrolled Experiment: Cause-to-Effect

An interesting concept from Chapter 15 of the text, was the uncontrolled experiment: Cause-to-effect. In this experiment, the possible cause is smoking; whereas the effect is lung cancer. During this study, researchers gathered two groups of people. One of the groups contained smokers, and the other contained people that claimed they never smoked. As this group was followed for over fifteen years, other possible factors of lung cancer were dismissed; and it was discovered that smoking was the common cause of lung cancers in the group that contained the smokers. This section later goes on to explain that since this experiment is uncontrolled, there can be many causes to the effect of lung cancer. It also goes to show that the process of eliminating those extra causes could be tedious. I enjoyed this section the most because it is realistic in showing that not all effects have just one cause.