QOL-24VALIDATION STUDY OF THE JAPANESE VERSION OF M.D. ANDERSON SYMPTOM INVENTORY BRAIN TUMOR MODULE (MDASI-BT)

Abstract

BACKGROUND: It has been recognized that symptom burden reported as a patient-reported outcome is valuable in assessment of both disease and treatment-related symptoms and should be incorporated into evaluation of clinical benefit of novel therapies. MDASI-BT is a widely-used instrument for measuring symptom burden in brain tumor patients, and its Japanese version (MDASI-BT-J) has recently been validated linguistically. The purpose of this study is to psychometrically validate MDASI-BT-J. METHODS: Patients with brain tumors who were undergoing oncologic treatments in The University of Tokyo Hospital or National Cancer Center Hospital between 2014 and 2015 were asked to fill out MDASI-BT-J and the Japanese version of European Quality of Life-5 Dimensions (EQ-5D-J). Feasibility, reliability, and validity of MDASI-BT-J were assessed. RESULTS: One-hundred-and-forty patients (72 men) including 63 patients with gliomas participated in the study. The median age was 54 years, and the median Karnofsky Performance Status (KPS) score was 90. The mean symptom severity score (MSS) and mean interference score (MIS) were 1.9 ± 1.7 and 2.8 ± 2.7, respectively. The median amount of time required to complete the form was 4 minutes (range, 0-30), and missing values were seen in 1%. Internal consistency using Cronbach's coefficient alpha was 0.94 and 0.92 for symptom severity and interference, respectively. Test-retest reliability was assessed in 30 patients with acceptable intra-class correlation coefficient (mean, 0.74). Known-group validity confirmed a significant difference in MSS (1.6 versus 2.3, P = 0.007) and MIS (2.0 versus 3.9, P = 0.007) between patients with KPS score >= 90 and those with KPS score <90. As evidence of concurrent validity, EQ-5D-J correlated with MDASI-BT-J in the hypothesized magnitude and direction. CONCLUSIONS: The current study endorses reliability of the newly-developed MDASI-BT-J in evaluation of clinical benefit in brain tumor patients in Japan. It is being used as one of the secondary endpoints in a multi-center prospective study for newly-diagnosed glioblastoma.