Reliability and Validity of the Greek QLQ-C30 and QLQ-MY20 for Measuring Quality of Life in Patients with Multiple Myeloma

Abstract

Objectives. The aim of this study was to assess the psychometric properties of the Greek EORTC QLQ-C30 and QLQ-MY20 instruments. Method. A sample of myeloma patients (N = 89) from two tertiary hospitals were surveyed with the QLQ-C30, QLQ-MY20 and various demographic and disease related questions. The previously validated Greek SF-36 instrument was used as a “gold standard” for health-related quality of life (HRQoL) comparisons. Hypothesized scale structure, internal consistency reliability (Cronbach's alpha) and various forms of construct validity (convergent, discriminative, concurrent and known-groups) were assessed. Results. Multitrait scaling confirmed scale structure of the QLQ-C30 and QLQ-MY20, with good item convergence (96% and 72%) and discrimination (78% and 58%) rates. Cronbach's α was >0.70 for all but one scale (cognitive functioning). Spearman's correlations between similar QLQ-C30 and SF-36 scales ranged between 0.35–0.80 (P < 0.001). Expected interscale correlations and known-groups comparisons supported construct validity. QLQ-MY20 scales showed comparatively lower correlations with QLQ-C30 functional scales, and higher correlations with conceptually related symptom scales. Conclusions. The observed psychometric properties of the two instruments imply suitability for assessing myeloma HRQoL in Greece. Future studies should focus on generalizability of the results, as well as on specific issues such as longitudinal validity and responsiveness.

Prevalence of symptoms in patients with multiple myeloma: a systematic review and meta‐analysis

“…Sexual problems in particular were also reported by patients with newly diagnosed disease pretransplantation . The same was observed for financial difficulties, present in newly diagnosed samples, samples with mixed disease stages and studies reporting baseline evaluation of SCT patients . A high prevalence of fatigue was also reported in these studies .…”

Cancer Related Fatigue and Quality of Life in Patients with Advanced Prostate Cancer Undergoing Chemotherapy

“…It includes subscales assessing urinary symptoms (9 items), bowel symptoms (4 items), treatment-related symptoms (6 items), and sexual functioning (6 items) [ 18 ]. The questionnaire has been translated and validated in several languages including Greek [ 20 ].…”

Psychometric Analysis of a Persian Version of the European Organization for Research and Treatment of Cancer OG25 Quality of Life Questionnaire in Oesophagogastric Cancer Patients

“…2011; Kontodimopoulos et al, 2012), including Iranian patients (Montazeri et al, 1999). Responses to the core questionnaire and the modules were linearly converted into 0-100 scores using standard EORTC guidelines (Fayers et al, 2001).…”