Informed decision making and prostate specific antigen (PSA) testing for prostate cancer: A randomised controlled trial exploring the impact of a brief patient decision aid on men's knowledge, attitudes and intention to be tested
Watson E., Hewitson P., Brett J., Bukach C., Evans R., Edwards A., Elwyn G., Cargill A., Austoker J.
Objective: To examine the impact of a brief patient decision aid (pDA) on men's knowledge, attitudes and intention to have a prostate specific antigen (PSA) test. To explore the important predictors of intention to be tested in men who received the brief pDA. Methods: A brief pDA designed to facilitate informed decision-making for men considering PSA testing was developed for the NHS Prostate Cancer Risk Management Programme. Men aged 40-75 years selected from 11 General Practices in England and Wales were randomised to receive either a mailed copy of the brief pDA and a questionnaire (intervention group), or a questionnaire alone (control group). The questionnaire assessed knowledge, attitudes, perceived risk and intention to have a PSA test and, for the intervention group, their perceptions of the brief pDA. Results: Nine hundred and ninety of the men who were eligible for the study returned completed questionnaires (response rate = 54%). Men who received the brief pDA had significantly higher knowledge scores (p < 0.0001) and less positive attitudes (p < 0.0001) regarding PSA testing than men in the control group. There was no significant difference between the two groups in intention to be tested within the next 12 months. 87% of men found the brief pDA was easy to read, 94% considered it contained about the right amount of detail and 94% felt the information was presented in a balanced way. Multivariate analysis identified perceived risk (p < 0.0001), perceived benefits of PSA testing (p < 0.0001), knowledge (p = 0.004), attitude (p = 0.007) and age (p = 0.01) as the most important independent predictors of intention to be tested amongst men in the intervention group. Conclusion: The brief pDA was shown to dramatically increase men's knowledge of the benefits and risks of the PSA test. Men who received the brief pDA were significantly less positive about the PSA test, although there was no difference between the two groups regarding their intention to be tested within the next year. Practice implications: This brief pDA could serve as an acceptable and low cost adjunct to counselling by the General Practitioner (GP), and should promote informed decision making regarding the PSA test. Further research is required to ascertain the utility of the decision aid during the consultation. © 2006 Elsevier Ireland Ltd. All rights reserved.