Effect of Handing a Written Document to Share Concerns and Values with Physicians When Making Decisions about Starting Drug Treatment among Patients: A Pre-post Quasi-Experimental Study with Propensity Score Matching

Background: There is lim ited evidence on the effectiveness of decision aids in promoting clinicians' understanding of patients' subjective perceptions. The aim of this study was to assess the impact of using a standard patient-completed template to express patients' views, preferences or concerns to their clinicians in a clinical decision-making setting on patients' perceived decisional conflict and post-decision regret. Methods: A pre-post quasi-experimental study with a six-month control period followed by a 12-month intervention period was conducted. Participants were recruited from six teaching hospitals and two clinics in Japan. The target population included 150 patients with diabetes mellitus, hypertension, and/or dyslipidaemia whose physicians had recently suggested drug treatment as a medical option. In the control period, a general informed consent booklet was distributed, and in the intervention period, a shared decision-making template was also provided. Patients were asked to complete the template, which was then attached to their electronic medical records. Results: Two months after enrolment, the decision conflict and regret scales were mailed to patients. Three months after enrolment, the decision status for starting drug treatment and the concordance between the patients' decision statuses and the initial medical recommendations were observed. Seventy-nine and seventy-one participants assigned to the control and intervention groups were enrolled. Fifty-five patient pairs generated by propensity score matching were analysed. No significant difference was observed between the two groups in the subscale scores of the decision conflict scale and the decision regret scale. The relative risk of patients with a decision status of ‘still considering’ starting drug treatment was 2.2 (95% CI, 1.02-4.9) in the intervention group. The concordance