Patient knowledge and misconceptions of osteoarthritis assessed by a validated self-completed knowledge questionnaire...

To design and validate an osteoarthritis (OA) patient knowledge questionnaire (PKQ-OA) and to use it to assess the patients' level of knowledge of their disease, treatments and appropriate management techniques.

The PKQ-OA comprises 16 multiple choice questions with 30 correct answers. It was developed in two phases and tested for face validity, readability (Flesch Reading Index) and understanding, reliability (Kuder-Richardson Formula 20) and reproducibility (test/retest). The questionnaire was then used to assess knowledge of disease and management of OA in a cohort of 83 patients with established disease.

The PKQ was found to be fairly easy to read, reliable (r = 0.75) and reproducible (r = 0.81; P < 0.01). The overall median score for the PKQ-OA was 19 ranging from 8 to 26. There was a highly significant association between the scores obtained and the number of years patients had spent in formal education, higher scores equating with greater length of education (P < 0.005). The majority of patients was knowledgeable about the symptoms of OA and exercise, but confused joint protection and energy conservation. The most worrying finding was the lack of knowledge regarding analgesics and some aspects of non-steroidal anti-inflammatory drug (NSAID) therapy. Less than a third of patients knew that analgesics could be taken prophylactically and 70% did not know that they should be taken when pain starts to build. Among the patients 34% did not know that NSAIDs should be taken with or following food.

The PKQ-OA is a readable, reliable and reproducible questionnaire. It is quick to complete and score and could be used in out patient clinics or GP surgeries to assess knowledge of patients with OA.