Guidelines for care increasingly help guide medical decision-making. If you’ve followed top health news over the past several years you’ve read conflicting statements about the utility of various medical procedures and tests. As a general internist I’ve devoured these reports with particular interest trying to wade through bias to formulate views that I believe will be of most benefit to my patients.

Recently I put together a talk about recommendations for prevention in women. As I prepared the talk I sorted through the data and opinions of various medical special interest groups.  Guidelines for care are usually developed by professional organizations or “expert panels,”  such as the Center for Disease Control (CDC), or the American Cancer Society (ACS).  One might like to think of these panels as unbiased in their advice, but clearly each expert panel is tainted, at least to a degree, by its own special interests.  Conflicting guidelines make it hard for health care consumers to figure out who to believe.

For example, several days ago the United States Preventive Services Task Force (USPSTF) came out with its final guideline on using PSA for the purpose of screening for prostate cancer. The task force recommended against using the test for screening healthy men, giving the screening test a D level rating (not recommended).

What is the USPSTF?

The U.S. Preventive Services Task Force (USPSTF), first convened by the U.S. Public Health Service in 1984, and since 1998 sponsored by the Agency for Healthcare Research and Quality (AHRQ), is the leading independent panel of private-sector experts in prevention and primary care. The USPSTF conducts rigorous, impartial assessments of the scientific evidence for the effectiveness of a broad range of clinical preventive services, including screening, counseling, and preventive medications. Its recommendations are considered the “gold standard” for clinical preventive services.

As a general internist I was indoctrinated to trust the USPSTF with a degree of allegiance that rivals my commitment to the University of Michigan Wolverines (my alma mater).  Nonetheless, there are other expert opinions that I also pay attention to.  In the case of PSA screening the American Urological Association (AUA) continues to make a strong argument supporting its use in screening. I discuss the debate more in my previous post:  Should Doctors Stop Using PSA to Screen for Prostate Cancer?

Another example of conflicting opinions in medical guidelines:  Who should be screened for diabetes?  The American Diabetes Association (ADA) recommends that all adults with a body mass index >25 kg/m2 (overweight or obese adults) and one additional risk factor for diabetes be screened at least every three years, and that all adults with a BMI>25kg/m2 who are over 45 years of age be screened. In contrast, the USPSTF recommends for screening only adults with blood pressure greater than 135/80, a grade B (recommended) rating. For other healthy adults, overweight or not, it advises that the evidence is insufficient to recommend for or against screening.

These are but two examples of the numerous medical guidelines and recommendations that conflict:  who should be screened for HIV, whether women ages 40 to 50 should be screened routinely for breast cancer with mammograms, how often women over 50 should be screened with mammograms, how often women under 30 should have a pap smear, whether women need an annual pelvic exam, whether women need an annual breast exam, and at what age screening for colon cancer with colonoscopy should be discontinued.  The ADA,  the USPSTF, the CDC, the American College of Obstetrics and Gynecology (ACOG), the ACS, the AUA, the American Heart Association and American College of Cardiology—along with numerous other professional societies and expert groups have not reached consensus on various matters.

Primary care doctors, as a group, have largely been supportive of proposed measures to reduce medical “waste”—including “unnecessary” tests and procedures that promise to bankrupt Medicare if they continue to go unchecked. In turn we stand to benefit from proposals to re-organize health care delivery and to strengthen primary care–the Medical Home Model, which may channel additional funds toward primary care. In comparison to specialists, primary care physicians have suffered in recent decades, with reimbursement policies that favor physicians who do procedures, as opposed to those who primarily talk to patients for a living.

We have been historically under-represented in the American Medical Association, the largest physician’s professional group in our country. I am part of the American College of Physicians (ACP), a national organization of internists — physicians who specialize in the prevention, detection and treatment of illnesses in adults–but recognize that we also have bias—currently, in my view, a growing skepticism of tests and procedures,  which in many ways is overdue. Yet I would wager that it’s a sentiment that primary care physicians find easier to rally behind than do many specialists, whose interests are more likely to be threatened by changes to reimbursement policy.

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.

Juliet K. Mavromatis is an internal medicine physician who blogs at Dr Dialogue.

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