Patient preference in a crossover clinical trial of patients with osteoarthritis of the knee or hip: face validity of self-report questionnaire ratings.

摘要: OBJECTIVE: To analyze correlational validity of self-report responses regarding patient preference between 2 drugs at the conclusion a crossover double-blind clinical trial in patients with osteoarthritis (OA) knee or hip. METHODS: Patients were randomized to 6 weeks9 treatment diclofenac/misoprostol acetaminophen, followed by weeks other drug. Patient was queried final visit: "Please compare control your arthritis during first and second periods as 9much better9 9better9 period, 9no different9 period." ratings evaluated comparisons 4 independent measures within each period: (1) change Western Ontario McMaster (WOMAC) questionnaire scores; (2) pain visual analog scale (VAS) on multidimensional Health Assessment Questionnaire (MDHAQ); (3) drug efficacy; (4) report status, well investigator more efficacious RESULTS: Among 173 patients, rated "much better" 54 "better" 45, acetaminophen 18 17, "no difference" 39 patients. Spearman rank correlations for preferences significant changes WOMAC scores, VAS, efficacy status physician (p