Chapter 12, Problem 3SE

Marijuana Use and Bone Density In a 2017 study reported in The American Journal of Medicine, Sophocleous et al. studied 170 adults who smoked marijuana regularly and 114 adults who had never used the drug and found that people who regularly smoke large amounts of marijuana may be more susceptible to bone fractures than people who don’t use the drug. Was this a controlled experiment or an observational study? Explain.