French adaptation and validation of the Osteoarthritis Quality of Life scale.

OBJECTIVE: The Osteoarthritis Quality of Life scale (OAQoL) is an osteoarthritis-specific measure developed in the United Kingdom by a needs-based approach. This study describes the adaptation and validation of this English scale into French. METHODS: The OAQoL was translated into French by a dual-panel technique followed by cognitive debriefing interviews. Internal consistency was assessed by the Cronbach α. Construct validity was tested by exploratory and confirmatory factor analyses and by convergent and divergent correlations with other patient-reported outcome measures by the Spearman rho (ρ). Reliability was explored by Spearman rho as well as the Bland and Altman method for the total score and Cohen's kappa for each item score. RESULTS: Cognitive debriefing revealed the French OAQoL to be clear, relevant and comprehensive. The Cronbach α was 0.91. Exploratory factor analysis extracted 4 groups of items. After eliminating 4 items, confirmatory factor analysis of the remaining 18 items confirmed higher intra-factor than inter-factor correlations. The expected convergent and divergent correlations were observed. Test-retest reliability was good (ρ 0.93) and was confirmed by Bland and Altman analysis; most items (12/18) had kappa values from 0.61 to 0.80. CONCLUSION: The French OAQoL is an easy-to-use 18-item questionnaire with good content and construct validity to assess the impact of osteoarthritis on quality of life for French-speaking patients.

Influence of flare design on symptomatic efficacy of non-steroidal anti-inflammatory drugs in osteoarthritis: a meta-analysis of randomized placebo-controlled trials.

INTRODUCTION: Non-steroidal anti-inflammatory drugs' (NSAIDs) symptomatic efficacy in osteoarthritis (OA) is often assessed in trials with a "flare design", i.e., including only patients with an increase in their pain after stopping their usual treatment (NSAIDs or analgesic). OBJECTIVE: To evaluate the influence of the "flare design" on NSAIDs apparent symptomatic efficacy in OA. SEARCH STRATEGY: a systematic literature research was performed in Medline, EMBASE and The Cochrane Register up to March 2009. All randomized controlled trials comparing NSAIDs vs placebo symptomatic efficacy in hip, knee, or digital OA were included. DATA COLLECTION AND ANALYSIS: efficacy was evaluated on pain (visual analog scale), and on function (Western Ontario and McMaster Universities OA index or Lequesne index). The magnitude of the treatment effect was evaluated by calculating Cohen's effect size (ES). Meta-analysis of ES according to flare design yes/no was performed. RESULTS: Among the 343 identified studies, 33 (20,915 patients) were included: 27 (18,667 patients) vs 6 (2248 patients) respectively in the group with vs without "flare design". Populations were comparable in each group. ESs were, for pain, -0.66 (95% confidence interval, -0.71 to -0.61), vs -0.45 (-0.54 to -0.36) in the flare design vs "no flare design" group, and for function, -0.50 (-0.55 to -0.44) vs -0.25 (-0.36 to -0.14) respectively. CONCLUSION: Our study suggests that the flare design used in clinical trials evaluating NSAIDs results in a treatment effect of higher magnitude. These results should be considered when designing a trial and/or interpreting the results of a trial.