Authors Barry MJ, Wexler RM, Brackett CD, et al.
Review Date August 2015
Citation Am J Prev Med 2015: doi: 10.1016/j.amepre.2015.03.002. [Epub ahead of print]
The risks and benefits of prostate-specific antigen (PSA) testing is controversial, with most guidelines recommending that shared decision making (SDM) between doctor and patient take place to decide whether it is appropriate for the individual patient. However, little research has been conducted on how best to incorporate SDM into PSA screening and how this may affect men’s decision making.
To report the proportion of patients who wanted PSA screening after engaging in SDM to learn about the risks and benefits of screening, and to describe the relationship between SDM and participants’ decisions.
This US study was conducted at two fee-for-service primary care practices based at academic medical centres. The decision aid (The PSA test: Is it right for you?) was developed by the Informed Medical Decisions Foundation and Health Dialogue, and was in the format of a 31 minute video presenting options for deciding to have or not have the PSA test to screen for prostate cancer. Men were eligible to view the decision aid if their doctor considered them to be a candidate for screening and they had not previously been diagnosed with prostate cancer.
Participants viewed the decision aid outside of their doctor appointment, and completed a questionnaire before and after viewing. The pre-viewing questionnaire assessed men’s baseline attitudes towards being screened, their readiness to decide, and their preferred role in decision making. The post-viewing questionnaire included these same items, another asking whether they intended to discuss PSA testing with their clinician, five knowledge questions about PSA screening, demographics, and prior history of PSA screening. Participants were also asked how much of the video they had watched.
A total of 1041 participants returned both pre- and post-viewing questionnaires, giving a response rate of 25% for the first site and 29% for the second site. Approximately half of the participants were aged 50-59 years, and half had had a prior PSA test. Participants were predominantly Caucasian and college educated. Eighty-three percent of participants reported viewing the decision aid in its entirety and 70% of participants had all five knowledge questions correct.
After viewing, there was a significant increase in the proportion of men leaning away from PSA screening, with 44% leaning away and 38% leaning toward. The largest pre-to-post change occurred in men who were unsure about screening pre-viewing (pre: 32%; post: 17%). The majority of men (pre: 58%; post: 55%) wished to share the decision to be screened with their doctor. Men who performed better on the knowledge questions were more likely to lean against screening and less likely to be unsure.
Viewing a decision aid reduced men’s interest in PSA screening, primarily those who were undecided prior to viewing the aid. Clinicians may wish to consider the use of decision aids to facilitate SDM between them and their patients with regards to PSA screening for prostate cancer.
Points to Note
- Given the controversy of the PSA test for prostate cancer, it is essential that patients give their informed consent to being screened. However, little research had been conducted to demonstrate how best to do this in the busy clinical environment.
- Men prescribed a decision aid as part of routine care to facilitate decision making about prostate cancer exhibited high knowledge of PSA screening and (post-viewing) became less likely to intend to be screened, with the biggest change occurring among those who were undecided pre-viewing. Men who were more knowledgeable on PSA screening were more likely to lean away from it.
- Limitations of the study include the low response rate, which may have introduced bias, and no validation of discussions with clinicians or PSA screening behaviour.
- Further research is needed to examine how decision aids and pre-visit perceptions and intentions affect the content of the following doctor visit.
- The decision aid was prescribed at the individual discretion of the clinician; the findings may have been different the decision aid had of been prescribed to all men eligible for screening.
- Given the lack of diversity in the study sample, the findings may not translate to minority groups, including African American men (and Australian Indigenous men) who have a higher risk of prostate cancer mortality.