A RANDOMIZED PILOT STUDY COMPARING THE EFFECTIVENESS OF DECISION AIDS FOR HIP AND KNEE OSTEOARTHRITIS

Purpose: This pilot study examined the comparative effectiveness of two decision aids (DAs) for hip and knee osteoarthritis (OA).

Method: Eligible hip and knee OA patients at 2 hospitals were randomly assigned to receive a short or long DA before their visit with a surgeon.  The short DA is a 16 page booklet which includes a knowledge test and values clarification exercise. The long DA is a 40 page booklet and 40 minute DVD which includes patient testimonials and detailed data on options and outcomes.  Participants completed a short survey, after receiving the DA and before their visit, assessing treatment preferences, knowledge, DA usage, health literacy, and quality of life (EQ-5D).  We compared the two DAs on (1) amount of use, (2) knowledge, and (3) treatment preference using t-tests and Pearson chi-square.

Result:

Overall response rate was 73.4%, 25/37 for the long DA arm and 33/42 for the short DA arm (67.6% vs. 78.6%, p=0.32). There were no significant differences in age, gender, joint, or education between groups. The long DA group had higher EQ-5D scores (0.72 vs. 0.61, p=0.016). 

The short DA group reported higher rates of reviewing all the DA compared to the long DA group (64.5% short vs. 24.0% long, p=0.003).  Patients with lower literacy were as likely to review all of the long and short DAs as those with high literacy (p=0.6).  Knowledge scores were not significantly different between arms (55.2% short vs. 48.8% long, p=0.4).  In the long DA arm, patients who reviewed all the DA had higher knowledge scores than those who did not (80.0% vs. 38.9%, p=0.004), whereas in the short DA arm, the knowledge scores were similar (62.0% for those who viewed all DA vs. 52.7% those who did not, p=0.27). A similar percentage of each group preferred surgery (54.5% short vs. 52.0% long, p=0.81).   

Conclusion: Despite having different content and formats, the two DAs had similar overall effectiveness. Patients were more likely to review the short DA; however, patients who reviewed all the long DA had the highest knowledge scores. Health literacy was not related to use of either DA. A larger study should examine the use and impact of the tools and determine whether patients are more likely to receive preferred treatments based on their DA assignment.