Self-administered patient questionnaire for assessing knowledge about joint arthroplasty prior to surgery

This article assesses the discriminant validity of a questionnaire designed to test patients' knowledge about total joint arthroplasty prior to preoperative educational intervention. The method employed was to compare responses on the test by surgeons, health care workers, and patients and to evaluate whether the test could discriminate among groups. A total of 148 patients, 59 health care workers and 28 orthopedic surgeons completed the questionnaire. The results show that patients are knowledgeable about the benefits of surgery, but are in need of information about surgical risks and complications. The test was able to discriminate between surgeons and the other two groups, but there were few differences between health care workers and patients. Item analysis also demonstrates that the test is reliable. Although the test exhibits acceptable psychometric properties, a major problem in using this test in evaluating educational interventions is the relatively high average score and the potential ceiling effect that prevents measurement of further gains in knowledge. More work is needed on expanding the test to include more items where knowledge of total joint arthroplasty is limited.