For at least several years, the American Cancer Society, the American College of Preventative Medicine, the American Urological Association, and the United States Preventative Services Task Force (USPSTF) have all said that men above the age of 75 should not be screened for prostate cancer. The USPSTF goes further and recommends against screening at any age. Yet, a recent estimate is that well over half of men ages 75-79 years were screened for prostate cancer. Why? To find out, Craig Pollack and colleagues surveyed primary care providers and published the results in Cancer earlier this year.

The most frequently cited reason was, ‘‘My patients expect me to continue getting yearly PSA tests’’ (74.4% of providers agreed) followed by, ‘‘It takes more time to explain why I’m not screening than to just continue screening’’ (66.4%). [...] Along with difficulty estimating life expectancy, many providers reported that patients’ expectations were a barrier to discontinuing screening. This is consistent with studies on older patients’ expectations about discontinuing cancer screening. Interviews with older adults indicate that 62% of older adults believed their own life expectancy was not important in their decisions to continue cancer screening, and 48% did not want to discuss their life expectancy with their clinician.
Patient demand and expectations are almost reasonable reasons, but only if those patients are well-informed. Given that the majority of respondents said that it takes too much time to explain the screening, I'm very skeptical that we're dealing with well-informed patients here. A reasonable inference is that most of those 75+ year olds don't understand the value and risks of a PSA test at their age. Does the practitioner have an ethical responsibility to obtain informed consent? Well, that's a tricky question, but a good one. One might reasonably wonder why the recommendations of the august bodies listed at the top of this post, including the USPSTF, aren't sufficient to inform the public. Doesn't that take the burden off the provider? I don't think so. Consumers are likely still to be confused, as Hal Arkes and Wolfgang Gaissmaier explain:
When a reader of the USPSTF report tries to digest the information about statistical lives, this information does not have the same impact as information, say, about the reader’s mail carrier’s older brother who had a positive PSA test, a biopsy, and a radical prostatectomy, and is now still alive.
Arkes and Gaissmaier go on to suggest other ways of communicating the statistical information to make it more accessible to the consumer. I still think the anecdote will have greater psychological power even though it should not. If one tries to apply, say, AHRQ's strength of evidence guidelines to anecdotes it is abundantly clear how weak they are. Every single one is woefully biased. A large, self-proclaimed treatment effect ("it saved my life") should be instantly downgraded to noise because no good estimate of the counterfactual (what would have happened in the absence of treatment to an otherwise identical individual) is available. I'm sure most readers of this blog know this already, but we're likely in the minority. Most consumers are poor judges of what's good quality, necessary health care. To the extent that they rely on the advice of trusted sources, that suggests that a conversation with a physician -- or use of some other decision aid that makes the statistical more personal -- is the right way to deliver the message.  

Austin Frakt is a health economist at the Department of Veterans Affairs and Boston University’s Schools of Medicine and Public Health. He blogs on health economics and policy at The Incidental Economist.

As part of our ongoing effort to raise awareness of health services research and increase its application in policy and practice, AcademyHealth has partnered with Austin Frakt, Ph.D., and Aaron Carroll, M.D., M.S., to contribute posts on the subjects of health care costs, delivery system transformation, and public and population health – areas AcademyHealth has identified as a priority in the current policy environment. As regular contributors, they’ll be discussing current events with an eye toward how new and existing research informs the issues.