Protocol for a randomised trial evaluating the comparative effectiveness of strategies to promote shared decision making for hip and knee osteoarthritis (DECIDE-OA study)

Abstract

Introduction: There are several different interventions available to promote shared decision making (SDM); however, little is known about the comparative effectiveness of different approaches.

Objective: To examine the impact of patient-directed and physician-directed decision support strategies on the quality of treatment decisions for hip and knee osteoarthritis (OA).

Trial design: A 2×2 factorial randomised controlled trial.

Setting: One academic medical centre, one community hospital and one orthopaedic specialty hospital.

Participants and interventions: The enrolment targets were 8 surgeons and 1120 patients diagnosed with hip or knee OA. Patients were randomly assigned to receive one of two different decision aids (DAs) stratified by site. The DAs varied in length, content and the level of detail regarding treatment options. Both DAs were available by paper or online.Surgeons were randomly assigned to receive a report detailing patients' goals and treatment preferences at the time of the visit or not. Eligible patients received their assigned DA before their visit and completed three surveys: before the visit (timepoint (T)1), 1-week postvisit (T2) and 6 months from either the visit date or surgery date for patients who underwent surgery (T3). Study staff and participating surgeons were not blinded, but the statistician conducting the analyses was blinded to the arms.

Main outcome measure and analysis: The primary study outcome was decision quality, the percentage of patients who were well informed and received their preferred treatment. Secondary outcomes included involvement in decision making, surgical rates, health outcomes, decision regret and satisfaction. A logistic regression model with the generalised estimating equations approach was used to compare rates of decision quality between the groups and account for the clustering of patients within providers.

Ethics and dissemination: Ethics approval was obtained through the institutional review board at the main site. The findings will be published in peer-reviewed journals.

Trial registration number: NCT02729831; Pre-results.

Keywords: comparative effectiveness; decision aid; osteoarthritis; shared decision making; surgery.

Conflict of interest statement

Competing interests: KS (PI) has received salary support as a medical editor for the Informed Medical Decisions Foundation (IMDF). From 1997 to 2014, the IMDF was associated with Health Dialog; from 2014 to 2017, the IMDF was part of Healthwise and in 2017, the IMDF became part of Massachusetts General Hospital. AAF reports other from Zimmer Biomet, ArthroSurface, CeramTec and Orthopaedic Technology Group, outside the submitted work. HB reports personal fees from Smith & Nephew and Conformis, outside the submitted work.

© Author(s) (or their employer(s)) 2019. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.

Figures

Figure 1

Flow of study interventions and assessments.

Figure 2

Consolidated Standards of Reporting Trials flow diagram estimating patient screening, enrolment and response rate. DA, decision aid; PPR, patient preference report; T1, previsit/in clinic before surgeon visit; T2, 1 week postvisit; T3, 6–12 months postvisit.