Should patient decision aids (PtDAs) be introduced in the health care system?





The issue

“Grey zone” treatments are those that rely upon the patient’s judgement of associated benefits versus harms. When clinicians judge patients are eligible for “grey zone” treatments, their acceptance should be consistent with informed patients’ values. The question is how can one obtain informed patient values? Patient decision aids (PtDAs) are interventions designed to help patients discuss treatment options with their clinicians and make specific, deliberative choices. They are used as an adjunct to counselling (not a replacement). The aim of PtDAs is to improve decision quality and to reduce unwarranted practice variations. There are over 500 PtDAs, many of which are available on the Internet.


This synthesis summarized the results of 23 PtDAs for treatment decisions that were evaluated in 29 randomized controlled trials. Most of these trials demonstrated that PtDAs were superior to comparison interventions in improving indicators of decision quality such as knowledge of the facts about options, realistic perceptions of outcome probabilities, and agreement between patients’ values and choice. In addition, patients who used decision aids had lower decisional conflict, participated more actively in decision-making, and were less likely to remain undecided. Exposure to PtDAs reduced opting for elective invasive surgical procedures in favour of conservative options by 24%, without adverse effects on patients’ health outcomes, satisfaction, or anxiety. The effects on other treatments were more variable. There is insufficient evidence on the effects of PtDAs on continuance of chosen options, implementation of PtDAs in diverse patient populations, and cost–effectiveness.

Policy considerations

The quality of decisions for grey zone treatment options is inadequate and is likely to be leading to over-use of treatment options that informed patients don’t value. PtDAs support patients in making evidence-informed choices and may be able to assist policy-makers in setting benchmarks for over-use of grey zone treatments, so resources could be freed up to promote the choice of more effective treatments. Given the proliferation of PtDAs in recent years, universally accepted quality standards for the development and evaluation of PtDAs are needed. Furthermore, PtDA service delivery models (including practitioner training) should be developed in diverse populations, with evaluation of the effects of PtDAs on decision quality and variations in use of health services and costs.

Type of evidence used in this review

This review is based on a systematic review of randomized controlled trials evaluating the effectiveness of PtDAs.