Who does one believe? Professional guidelines are likely to shape what is covered by Medicare and private health insurance. If you’re a gynecologist you might trust ACOG, if you’re a primary care doctor, the USPSTF or the ACP, a urologist, the American Urological Association–the politics of medicine are as real as the patients that we treat. Moreover, advocacy groups, such as the Susan G. Komen Foundation and Planned Parenthood, play a role in shaping public opinion, which no doubt can also influence the opinion of even “expert panels,” afraid to anger these factions.
If you are a medical professional it’s important to be aware of where guidelines conflict and to avoid reflexively supporting one own expert panels. Even better (though more difficult), read through the original data. If you’re a patient, sometimes it’s good to get the opinion of both a specialist and a generalist in these matters—each can be equally valid and it can help one see both the trees and the forest.