Chapter 2, Problem 69CR

The article “Tots’ TV-Watching May Spur Attention Problems” (San Luis Obispo Tribune, April 5, 2004) describes a study that appeared in the journal Pediatrics. In this study, researchers looked at records of 2500 children who were participating in a long-term health study. They found that 10% of these children had attention disorders at age 7 and that hours of television watched at age 1 and age 3 was associated with an increased risk of having an attention disorder at age 7.

1. a. Is the study described an observational study or an experiment?
2. b. Give an example of a potentially confounding variable that would make it unwise to draw the conclusion that hours of television watched at a young age is the cause of the increased risk of attention disorder.