■ Safety of care:

Improving patient safety and reducing risks

Engaging patients in their own care: Patient decision aids

Female patient and female doctor both wearing protective face masks at a medical clinic.

6 minutes

Published: December 2020

The information in this article was correct at the time of publishing

Physicians sometimes ask patients to make decisions where the answer will depend on the patient’s unique perspective and circumstances. For instance, you may offer a lung cancer screening test to two patients who are both heavy smokers. One may welcome the test as a chance for early intervention, while the other may see the risk of false positives as potentially doing more harm than good.

Patient decision aids (PDAs) can help your patients make decisions in situations where the potential benefits are not clear-cut and where the outcome will be determined largely by patient preferences and values. While general health literacy materials help people understand a particular illness, diagnosis, or treatment, PDAs are verified, evidence-based resources focused on specific decision points.1 The tools are aimed at situations where patients need assistance in thinking through benefits, harms, probabilities, and how well a treatment or screening might accord with their values.1 The tools should always complement, rather than replace, an informed consent discussion.

PDAs encourage shared decision-making

Patient decision aids can be an effective way of encouraging patients to participate in their own care. The process of shared decision-making treats the patient as an expert in their own life and circumstances, and makes them active participants in major care and treatment decisions. Shared decision-making features an exchange of information between physician and patient, rather than a one-way stream of information from physician to patient.

PDAs can be effective in facilitating this two-way flow of information and helping the patient make difficult decisions. PDAs increase patients’ knowledge of their health conditions, improve the accuracy of their risk perceptions, and create a better fit between their values and the care decisions they are making. While PDAs may slightly increase appointment times, they can decrease the number of patients unable to make a decision and improve physician-patient communication overall.1

Case example: Using a PDA to respond to a request when screening is not indicated

During an appointment, a 45-year-old patient tells you that her friend has been diagnosed with breast cancer. Your patient has no family history of breast cancer, but she says she’s worried about her health and asks you to order a mammogram.

You know that the harms of mammograms outweigh the benefits for women in their 40s who are not at increased risk. However, you want to respond to the anxiety your patient is feeling. Using a PDA,2 you have an informed consent discussion about the risks associated with screening (especially false positives and unnecessary biopsies), as well as the minimal benefit (with less than one breast cancer death prevented per 1,000 women).

After the discussion, your patient is more reflective. She tells you she needs time to process the new information. You ask her to return in two weeks to continue the discussion about whether she would like the mammogram ordered. You give your patient the PDA to take with her and document your use of the aid, as well as any specific concerns your patient had.


Patient decision aid databases

There are well-recognized and sophisticated databases for PDAs online. The inventory of decision aids created by the Ottawa Hospital Research Institute is searchable by health topic and rates each aid according to a number of quality criteria.3 The Mayo Clinic Shared Decision Making National Resource Center provides aids related to a number of specific health conditions, such as osteoporosis and rheumatoid arthritis.4 Note that, if using an aid from an American or international source, you should ensure the aid is relevant within the Canadian context.

Using PDAs to promote safe care

When using PDAs, consider the following to promote safe care and reduce medical-legal risk.

1. Provide the PDA to your patient as part of a continued discussion

Generally speaking, it’s best to provide your patient with a PDA as part of a discussion about a proposed treatment or screening. This gives them time to review and reflect on the material. When you provide the PDA, tell your patient that, at the next appointment, they will have a chance to ask questions and fully discuss the decision in question.

Because PDAs are often provided to patients in advance of an informed consent discussion, consider in individual cases whether it is appropriate to use them with patients who are unlikely to follow-up for further discussion. In such cases, medical-legal difficulties may arise if a patient later claims they did not proceed with a treatment or screening because they did not understand the information set out in the PDA, and because there had been no informed consent discussion. In every case, document the information given to the patient, including the encouragement to return with questions and discuss care options further.

2. Only use PDAs in appropriate circumstances

Before using a PDA, consider whether the patient will understand the information as presented in the particular PDA. For example, aids may not be appropriate where there is a language barrier or cognitive impairment. The aids may also be ineffective when a patient has a low level of health literacy. A review of almost 100 PDAs found that only three had been designed for patients with lower health literacy levels, and that more tailored PDAs are needed to meet the needs of this group.5

3. Follow up with your patient

After using a PDA, assess how comfortable patients are with their decision, including how well they understand the information, how clear they are about risks and benefits, and whether they have any unanswered questions.5

After patients have made their decision, be sure to review the decision at a later date. This is especially critical if the patient’s risk factors change, or if there have been changes to other factors that have influenced the patient’s decision. A patient’s decision about a screening or treatment is rarely final, but can change as their circumstances change.6

4. Document your use of the PDA and print the aid where necessary

Document in the patient chart any PDAs provided to the patient, the patient’s decision, and the fact that the patient was given an opportunity to ask questions about the treatment before making a decision.

Since PDAs posted online are frequently updated or removed, consider archiving a copy of the specific aid that you used. This is particularly important because a legal action may not arise for years after the appointment, and you may need to point to specific aspects of the aid in question.

The bottom line

Patient decision aids can be a useful way of helping patients make treatment or screening decisions that are right for them. However, consider whether a specific aid is appropriate and helpful in the context of each patient. PDAs are not a substitute for informed consent discussions and should only be used as an adjunct to discussions tailored to the specific needs and circumstances of each patient. If you have general questions about the use of PDAs, contact the CMPA for advice.


  1. Stacey D, Légaré F, Lewis K, et al. Decision aids for people facing health treatment or screening decisions. Cochrane Database Syst Rev. 2017;4(4). DOI:10.1002/14651858.CD001431.pub5
  2. For example, see Canadian Task Force on Preventive Health Care. Breast cancer update – 1000 person tool.
  3. Ottawa Hospital Research Institute. Patient decision aids.
  4. Mayo Clinic. Mayo Clinic Shared Decision Making National Resource Center.
  5. McCaffery KJ, Holmes-Rovner M, Smith SK, et al. Addressing health literacy in patient decision aids. BMC Med Inform Decis Mak 2013;13 S10. DOI: https://doi.org/10.1186/1472-6947-13-S2-S10
  6. Grad R, Légaré F, Bell NR, et al. Shared decision making in preventive health care: What it is; what it is not. Can Fam Physician, 2017;63(9)682

DISCLAIMER: The information contained in this learning material is for general educational purposes only and is not intended to provide specific professional medical or legal advice, nor to constitute a "standard of care" for Canadian healthcare professionals. The use of CMPA learning resources is subject to the foregoing as well as the CMPA's Terms of Use.