Is a television (TV) in the bedroom associated with obesity? Researchers questioned 379 twelve-year old adolescents and concluded that the body mass index (BMI) of the adolescents who had a TV in their bedroom was significantly higher than the BMI of those who did not have a TV in their bedroom.
(a) Why is this an observational study? What type of observational study is this?
(b) What is the response variable in the study? What is the explanatory variable?
(c) Can you think of any lurking variables that may affect the results of the study?
(d) In the report, the researchers stated, "These results remain significant after adjustment for socioeconomic status." What does this mean?
(e) Can we conclude that a television in the bedroom causes a higher body mass index? Explain.