Abstract
OBJECTIVE: To evaluate the effectiveness of an online Patient Decision Aid (PtDA) for patients with Generalised Anxiety Disorder (GAD). DESIGN: Randomised controlled trial comparing the PtDA to general information (fact sheet). SETTING: The study took place in 17 primary care centres in the Canary Islands (Spain). PARTICIPANTS: Patients diagnosed with GAD and a score ≥8 in the GAD-7 questionnaire. INTERVENTION: Patients were randomly allocated to the PtDA group (n=58) or the control group (n=61). MAIN OUTCOME MEASURE: The primary outcome was decisional conflict at postintervention, assessed with the Decisional Conflict Scale (DCS). Secondary outcomes include knowledge about GAD and its treatments, concordance between informed preference and 3 month actual choice, decision quality and GAD symptoms. RESULTS: There were no significant differences in decisional conflict at postintervention or 3 month follow-up in the intention-to-treat (ITT) or per-protocol sample (PPS). The PtDA significantly improved postintervention (MD=1.65, 95% CI: 0.84 to 2.46) and 3 month objective knowledge (MD=0.78, 95% CI: 0.02 to 1.55). In the PPS, anxiety symptoms at 3 months were significantly lower in the PtDA group (MD=-3.00, 95% CI: -5.69 to -0.30), but in the ITT sample, this difference did not reach significance (p=0.06). There were no significant differences in the rate of patients unsure about treatment preference at postintervention, nor on concordance or decision quality at follow-up. CONCLUSION: The use of the PtDA led to improvements in knowledge at 3 months, but it did not result in a significant reduction of decisional conflict. These results must be interpreted with caution, given the methodological limitations of the study, mainly the high rate of dropouts. Further research is needed to confirm these results, the first published on the effectiveness of a PtDA for GAD patients. TRIAL REGISTRATION NUMBER: NCT04364958.