Translation and validation of the Chinese version of the short Warwick-Edinburgh Mental Well-being Scale for patients with mental illness in Hong Kong.

OBJECTIVE

Quality of life outcomes are useful in the assessment of mental and social wellbeing and for informed health care decision-making, especially in the choice of interventions in psychiatric rehabilitation. In its original form, the Warwick-Edinburgh Mental Well-being Scale (WEMWBS) is a proven reliable and valid tool for assessing quality of life in normal adults, but not in adults from Asian countries. A shortened 7-item version of WEMWBS (SWEMWBS) with good internal construct validity was used for this study. The present study describes the translation of WEMWBS from English to Chinese and its validation in a sample of Chinese-speaking patient population.

METHODS

Participants included patients admitted to the inpatient units, and those attending the day hospital and outpatient units of the Kowloon Hospital (n = 126). Translation was performed using the multiple forward and backward translation protocol. Patients also completed the 5-item World Health Organization Well-being Index (WHO5) questionnaire. A case therapist completed the Brief Psychiatric Rating Scale within 2 days. A total of 20 patients were selected for test-retest measurements performed after 2 weeks.

RESULTS

The sample displayed a normal distribution of the Chinese version of SWEMWBS (C-SWEMWBS) scores (mean ± standard deviation, 23.16 ± 5.39; skewness, -0.068; kurtosis, -0.355). Internal reliability coefficient (Cronbach's alpha) for C-SWEMWBS was 0.89 which was consistent with that of English version. The corrected item-total correlation was high with Spearman's rank correlation coefficients ranging from 0.57 (item 6) to 0.75 (item 5). Good test-retest reliability was observed (r = 0.677; p = 0.001). Principal components factor analysis identified a single component (eigenvalues, 4.28; 61.1% variance), similar to the English version. Scores of C-SWEMWBS were positively correlated with the scores of WHO5 (r = 0.49; p < 0.001), suggesting good concurrent validity. Few item scores including 'feeling useful', 'dealing with problems well', 'able to make decisions', and the total score were significantly correlated with diagnostic groups (p < 0.05). Education and diagnosis of mental illness were valid predictors for C-SWEMWBS (F = 5.41; p = 0.01). There were no effects due to age and gender.

CONCLUSION

The C-SWEMWBS showed high levels of internal consistency and reliability against accepted criteria. It is short, acceptable, and culturally meaningful to clients with mental illness. Further large-scale studies in normal subjects and varied patient groups are recommended to generalise the findings.