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Aims: The psychometric properties of the EORTC QLQ-BN20, a brain cancer-specific HRQOL questionnaire, have been previously determined in an English-speaking sample of patients. This study examined the validity and reliability of the questionnaire in a multi-national, multi-lingual study. Methods: QLQ-BN20 data were selected from two completed phase III EORTC/NCIC clinical trials in brain cancer (N =891), including 12 languages. Experimental treatments were surgery followed by radiotherapy (RT) and adjuvant PCV chemotherapy or surgery followed by concomitant RT plus temozolomide (TMZ) chemotherapy and adjuvant TMZ chemotherapy. Standard treatment consisted of surgery and postoperative RT alone. The psychometrics of the QLQ-BN20 were examined by means of multi-trait scaling analyses, reliability estimation, known groups validity testing, and responsiveness analysis. Results: All QLQ-BN20 items correlated more strongly with their own scale (r >0.70) than with other QLQ-BN20 scales. Internal consistency reliability coefficients were high (all α ⩾0.70). Known-groups comparisons yielded positive results, with the QLQ-BN20 distinguishing between patients with differing levels of performance status and mental functioning. Responsiveness of the questionnaire to changes over time was acceptable. Conclusion: The QLQ-BN20 demonstrates adequate psychometric properties and can be recommended for use in conjunction with the QLQ-C30 in assessing the HRQOL of brain cancer patients in international studies. [Copyright &y& Elsevier]

Abstract: Objective: To compare Cohen''s guidelines for small (0.2), medium (0.5), and large (0.8) effect sizes with empirical estimates for a cancer-specific health-related quality-of-life questionnaire (HRQOL), the Functional Assessment of Cancer Therapy - General (FACT-G). Methods: Seventy-one papers satisfied inclusion criteria for meta-analysis. Blinded to the HRQOL results, three “experts” (with expertise in interpreting the FACT-G questionnaire and managing cancer patients), predicted the relative magnitude of HRQOL mean differences. Size classes (small, medium, large) were defined in terms of relevance to clinical decision making. The experts worked independently and based their predictions on patient characteristics and clinical circumstances. Their judgments were linked with FACT-G results and inverse-variance–weighted mean effect sizes calculated for each size class. Results: At least two experts were perfectly concordant and up to one was discordant by at most one size category for 833 of the mean differences; for these, weighted kappas were generally in the “substantial” range (0.60–0.79). Of these mean differences, 617 were cross-sectional; small, medium, and large mean effect sizes were physical well-being 0.42, 0.87, 1.6; functional well-being 0.37, 0.71, 1.6; emotional well-being 0.32, 0.40, no large differences; and social well-being 0.14, 0.23, no large differences. Two hundred and sixteen longitudinal mean differences yielded small and medium effect sizes: physical well-being 0.26, 0.34; functional well-being 0.14, 0.28; emotional well-being 0.27, 0.23; and social well-being 0.08, 0.01. There was virtually no evidence for large longitudinal effects. Conclusion: These results provide specific, evidence-based alternatives to Cohen''s generic guidelines, for use in sample-size calculations for the FACT-G and interpretation of the clinical significance of effects measured with FACT-G. [Copyright &y& Elsevier]