Measuring breast cancer-specific health-related quality of life in South Asia: psychometric properties of the Sinhala version of the EORTC QLQ-BR23.
OBJECTIVE
To evaluate the psychometric properties of the Sinhala version of the breast cancer-specific health-related quality of life (HRQL) module of the European Organization for Research and Treatment of Cancer (QLQ-BR23).


METHODS
Psychometric testing assessed the hypothesized scale structure, internal consistency, construct validity and acceptability of the Sinhala version of the QLQ-BR23 in a consecutive series of 356 newly diagnosed breast cancer patients recruited from tertiary care oncology treatment centres in Sri Lanka.


RESULTS
Compliance and self-completion rates were high (98% and 88%, respectively), and missing data low (0.06%). Multitrait scaling confirmed the scale structure of the QLQ-BR23 with excellent item convergence (95%), item discrimination (99%), and scaling success (99%) rates. The Cronbach's alpha coefficients of the scales for internal consistency reliability ranged from 0.68 to 0.93. Construct validity was confirmed with satisfactory results for interscale correlations and known-groups comparisons. QLQ-BR23 item-scale correlations met or exceeded the convergent validity criterion of 0.40 for all but one item. QLQ-BR23 interscale correlations met this criterion for three comparisons and for five comparisons with conceptually related QLQ-C30 scales. Correlations between QLQ-BR23 scales and QLQ-C30 functional scales were lower as expected. As expected, most dimensions of the QLQ-BR23 were able to discriminate clearly between pretreatment and current treatment patients.


CONCLUSIONS
Overall psychometric results for the Sinhala version of the QLQ-BR23 confirmed it as a reliable and valid questionnaire for assessing breast cancer-specific HRQL in Sri Lanka.
Jayasekara
Harindra
H
Epidemiology Unit, Ministry of Health, No 231, De Saram Place, Colombo 10, Sri Lanka. hja@unimelb.edu.au
Rajapaksa
Lalini C
LC
Brandberg
Yvonne
Y
D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000523:psychology*; D003469:Culture; D005260:Female; D006801:Humans; D008875:Middle Aged; D011594:Psychometrics; D011788:Quality of Life / Q000523:psychology*; D015203:Reproducibility of Results; D013188:Sri Lanka; D011795:Surveys and Questionnaires