However, the gist of the article is that probably most of the earlier studies aren't adjusting for enough factors, and when someone did, the links went away. B

However, the gist of the article is that probably most of the earlier studies aren't adjusting for enough factors, and when someone did, the links went away. Basically, if your study says that taking Ambien doubles your risk of cancer, bubonic plague, dying in a plane crash (where you are not the pilot) and being shot by snipers, the study is probably wrong. Given that it's a drug taken for sleep difficulties, and the number of possible things that can cause sleep difficulties (near the top of the list: stress, from literally innumerable sources), and the fact that sleep difficulties take a medical toll, as well as do many of the primary, secondary, and tertiary causes of sleep difficulties, it's very hard to account for that in a study.