Responsiveness of the electronic touch screen WOMAC 3.1 OA Index in a short term clinical trial with rofecoxib.
BACKGROUND
The Western Ontario and McMaster Universities (WOMAC) Osteoarthritis Index is a self-administered validated questionnaire for patients with osteoarthritis (OA) of the hip or knee. The electronic touch screen version of the WOMAC (e-WOMAC) has been previously shown to be highly correlated with the original paper format. However, whether the e-WOMAC would be suitable for monitoring the effects of drug treatment is unknown.


OBJECTIVE
To validate the longitudinal use of the e-WOMAC questionnaire and its ability to detect changes in WOMAC-scores induced by drug treatment in outpatient care.


METHODS
Fifty-three outpatients, men and women (mean age: 64 years; SD+/-9.5), with symptomatic osteoarthritis of hip or knee were included in an open label study with rofecoxib. At three visits over 3 weeks, responsiveness of the WOMAC 3.1 regarding the three subscales, pain, stiffness and function, were compared for the original paper format and the computer touch screen format (QUALITOUCH) using a Likert scale. WOMAC scores were transformed to the 0-100 scale. ANOVA for repeated measures was used for analysis and effect sizes by subscale were compared for both formats.


RESULTS
Responsiveness for all three subscales was similar between formats. In both formats, pain and stiffness were significantly reduced with rofecoxib as early as 7 days, while functional ability was significantly increased (P<0.01 for all aggregate subscale scores) with continuing improvement until the end of study. The effect sizes by subscale between Day 1 and 21 were not statistically different between the paper and the electronic version of the questionnaire and showed similar clinically meaningful improvements in WOMAC scores over 3 weeks.


CONCLUSIONS
In this longitudinal intervention study, the e-WOMAC OA Index 3.1 showed similar responsiveness in detecting clinically meaningful changes than the original paper format.
Theiler
R
R
Rheumatology Clinic and Institute for Physical Medicine and Rehabilitation, Stadtspital Triemli, Zurich, Switzerland. robert.theiler@triemli.stzh.ch
Bischoff-Ferrari
H A
HA
Good
M
M
Bellamy
N
N
D000368:Aged; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000627:therapeutic use*; D016288:Computer Terminals; D005260:Female; D006621:Hip Joint / Q000503:physiopathology; D006801:Humans; D007719:Knee Joint / Q000503:physiopathology; D007783:Lactones / Q000627:therapeutic use*; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D010003:Osteoarthritis / Q000188:drug therapy* / Q000503:physiopathology; D015207:Osteoarthritis, Hip / Q000188:drug therapy / Q000503:physiopathology; D020370:Osteoarthritis, Knee / Q000188:drug therapy / Q000503:physiopathology; D010147:Pain Measurement / Q000379:methods; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D013450:Sulfones / Q000627:therapeutic use*; D011795:Surveys and Questionnaires; D016896:Treatment Outcome
D000894:Anti-Inflammatory Agents, Non-Steroidal; D007783:Lactones; D013450:Sulfones; C116926:rofecoxib