The problem of degenerative joint disease (DJD) is commonly found in domestic cats and accompanied by radiographic abnormalities and mobility impairment. There has been a lack of progress in establishing an effective therapeutic regimen for those cats affected due to a lack of validated owner-administered assessment methods. In other recent work, the authors have developed an owner-directed metrology instrument for musculo-skeletal pain (Feline Musculoskeletal Pain Index – FMPI) and the results determined that it discriminates well between normal cats and cats with DJD-associated pain with good internal consistency and repeatability.
This particular study’s purpose was to evaluate whether or not FMPI has responsiveness and criterion validity. “Responsiveness” of an instrument is defined as whether or not the instrument can detect a change in what it is measuring, for example, a change in status because of treatment. The description of “Criterion” validity refers to whether or not the results from the instrument correlate to a gold standard measure, if there is one. For this study, twenty-five client-owned cats with DJD associated pain were evaluated for FMPI responsiveness through a 10-week clinical study that was stratified, randomized, double blinded, placebo-controlled, and a cross-over. Meloxicam was the therapeutic administered to provide pain relief. The results showed a large placebo effect (76%) where the instrument did not detect any difference between placebo and meloxicam, even for high impairment cases. In this cohort of cats, the FMPI showed little responsiveness or criterion validity. Further work is needed to define and understand activity in cats with DJD pain. (VT)