Psychometric properties of the Arabic version of EORTC QLQ-C15-PAL among cancer patients in Jordan

One hundred seventy-five patients completed the EORTC QLQ-C15-PAL questionnaire. Cronbach’s alpha coefficient met the 0.7 alpha criterion. Confirmatory factor analysis met the goodness of fit criteria; goodness-of-fit index (GFI), comparative fit index (CFI), normed fit index (NFI) and non-normed fit index (NNFI) >0.90 and root mean square error of approximation (RMSEA) <0.06. All item-scale correlation coefficients exceeded the set value of 0.40, indicating satisfactory convergent validity. In terms of discriminant validity, all items in the questionnaire showed a higher item-scale correlation than item-other scale correlation, except for items 1 and 2 (physical function scale) that showed a higher correlation with fatigue. Construct validity was tested by item inter scale correlation coefficient. All constructs had correlation coefficient <0.70. External validity was tested by comparison of scores of patients who had metastasis and who did not have metastasis. Significant differences (P value <0.05) were found in all scales except for nausea. Age groups were compared and showed significant differences for physical function, fatigue, and global score of HRQOL.