Clinical investigation: Reliability and validity of the Japanese version of quality of life radiation therapy instrument (QOL-RTI) for Japanese patients with head and neck malignancies.
OBJECTIVE
To evaluate the reliability and validity of the Japanese translation of Quality of Life Radiation Therapy Instrument (QOL-RTI) and the head and neck module (H&N) for Japanese patients being treated with radiotherapy for head and neck malignancies.


METHODS
The QOL-RTI/H&N was translated into Japanese by a preliminary QOL research working group of JASTRO and was used in this clinical trial. From 1998 to 2001, 70 patients with head and neck malignancies for whom radical radiotherapy was planned were entered into this study. Patients were requested to answer the questions before radiotherapy at baseline, twice during week 4 of therapy (for test-retest reliability), at the end of treatment, and 3 months, 6 months, 1 year and 2 years from the beginning of radiotherapy. Internal consistency was assessed by Cronbach's alpha coefficient. Validity was assessed by comparing the results with EORTC-QLQ-C30 and with QOL questionnaire for cancer patients treated with anticancer drugs (QOL-ADC). Patient compliance and test sensitivity were also analyzed.


RESULTS
Cronbach's alpha coefficient was 0.79 to 0.93 depending on the time point for the evaluation. Test-retest reliability was acceptable, with a Pearson coefficient of 0.83 for QOL-RTI and 0.92 for H&N module. Compliance with this scheme was 98.2%. The QOL-RTI was sensitive enough to detect significant changes in the QOL score during and after the course of radiotherapy. Agreement with the EORTC-C30 was good with a high Pearson correlation coefficient of 0.648 and that with QOL-ADC was also good with a coefficient of 0.566. The factors analyzed consisted of 11 functional/health-oriented questions, 5 emotional/ psychological, 5 socio-economic/ family and 2 general.


CONCLUSIONS
The Japanese version of QOL-RTI with H&N module was found to be reliable and sensitive enough to evaluate variation of QOL in patients with head and neck malignancies during and after radiotherapy.
Karasawa
Kumiko
K
QOL Research Group of Jastro. kkarasaw@med.juntendo.ac.jp
Sasaki
Takehito
T
Okawa
Tomohiko
T
Takahashi
Takeo
T
Hayakawa
Kazushige
K
Ohizumi
Yukio
Y
Tamaki
Yoshio
Y
Makino
Masaoki
M
Kobyashi
Masao
M
Shibayama
Chiaki
C
Saitou
Tsutomu
T
Johnson
Darlene J
DJ
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006258:Head and Neck Neoplasms / Q000503:physiopathology / Q000523:psychology / Q000532:radiotherapy*; D019538:Health Care Surveys; D006302:Health Services Research; D006801:Humans; D007564:Japan; D008297:Male; D008875:Middle Aged; D011788:Quality of Life; D018787:Radiation Oncology; D012680:Sensitivity and Specificity; D018434:Sickness Impact Profile