Patient Education on Prostate Cancer Screening and Involvement in Decision Making

The study by Krist and colleagues in the March /April 2007 issue of Annals of Family Medicine provides important new insight on the use of prostate cancer screening decision aids in clinical practice: they may not promote shared decisions. Krist and colleagues performed a randomized trial of 497 men in a single academic family medicine practice to examine the effect of a prostate cancer screening decision aid in two forms: a Web -based version and a paper-based version, compared with usual care. As expected, they found that receipt of the decision aid before a scheduled health maintenance visit was associated with increased knowledge and a moderately lower likelihood of undergoing screening (94% in the usual care control group vs. 85-86% with receipt of the decision aid). Contrary to authors’ hypotheses, men in the decision aid groups were not more likely to report a shared decision; they were, however, more likely to report an increasingly active patient role in decision making. Those receiving the decision aid were somewhat (about 10%) more likely to report participating at their desired level, but this result did not reach statistical significance.

Considering how decision aids work, the authors’ findings should perhaps not be surprising. Decision aids may allow patients to make a high -quality decision about screening prior to consulting with their doctors. A shared decision would only need to occur if the doctor, with his or her unique view of the patients’ medical history, identifies additional decisional factors beyond those covered in the decision aid, or the patient desires help with the decision. (1)

How then should we assess the effect of a decision aid? The goal of a decision aid should be to ensure a high-quality decision making process. It is helpful to characterize the decision making process as having three elements: 1) communication of relevant knowledge about the health choice (options, benefits, risks, and uncertainties); 2) assessment of patient values; and 3) integration of the information from 1 and 2 into a final decision. (2) In the context of the PSA decision, we can define a high quality decision as one in which the patient has been informed about PSA screening (Step 1), has considered his values about the outcomes and uncertainties (Step 2), and this information has been integrated into a final choice (Step 3).

There are several ways this decision making process can be accomplished. For example, a clinician trained in shared decision making can, as part of a clinical encounter, provide the patient with appropriate information, assess his values, and then allow the patient to perform the integration (or if the patient prefers, perform the integration step for him). In this context, using the outcome of a shared decision would be appropriate. Alternately, an individual, with the help of a decision aid, can gain appropriate information and clarify his values. He can then perform the integration step himself, if he is comfortable, or discuss the decision with his clinician and perform the integration as part of shared decision making. When using a decision aid, the outcome of a shared decision alone seems insufficient to capture a good decision. In this trial, it appears that patients were often able to perform the integration of knowledge and values themselves, and hence were more likely to respond that they made the decision on their own. As long as the decision is informed and reflective of the patient’s values, this should be considered a successful process.

In practice and in research, the dilemma for promoting high-quality decision making is determining what constitutes “informed” and “reflective of the patient’s values.” This field of research remains relatively underdeveloped. We need additional methodological and practical studies, including qualitative research, to determine key knowledge domains and evaluate different techniques for assessing patient values.

References

1. Sheridan SL, Harris RP, Woolf SH; Shared Decision-Making Workgroup of the U.S. Preventive Services Task Force. Shared decision making about screening and chemoprevention. a suggested approach from the U.S. Preventive Services Task Force. Am J Prev Med. 2004 Jan;26(1):56-66.

2. Elwyn G, O'Connor A, Stacey D, Volk R, Edwards A, Coulter A, Thomson R, Barratt A, Barry M, Bernstein S, Butow P, Clarke A, Entwistle V, Feldman-Stewart D, Holmes-Rovner M, Llewellyn-Thomas H, Moumjid N, Mulley A, Ruland C, Sepucha K, Sykes A, Whelan T; International Patient Decision Aids Standards (IPDAS) Collaboration. Developing a quality criteria framework for patient decision aids: online international Delphi consensus process. BMJ. 2006 Aug 26;333(7565):417

Competing interests:   None declared