Validation of the scleroderma health assessment questionnaire and quality of life in English and Chinese-speaking patients with systemic sclerosis.
OBJECTIVE
To perform cross-cultural adaptation and validation of the Scleroderma Health Assessment Questionnaire (S-HAQ) and Systemic Sclerosis Quality of Life scale (SSc-QoL) in English and Chinese-speaking patients with SSc.


METHODS
In this Institutional Review Board approved study, patients seen at the rheumatology outpatient clinics were consecutively recruited over a 10-month period. We evaluated: (i) test-retest reliability using the intraclass correlation coefficient (ICC); (ii) known-groups construct validity by stratifying patients according to organ involvement and symptom severity; and (iii) convergent validity using Spearman's correlation with Short Form 36 version 2 (SF36v2).


RESULTS
Forty-nine SSc patients completed the questionnaires: 26 Chinese, 23 English; 30 self-administered, 19 interviewer-administered, of which 35 responded to the retest. The SSc-QoL, HAQ Disability Index, intestinal Visual Analogue Scale (VAS), breathing VAS and overall disease severity VAS demonstrated high reliability (ICCs 0.71-0.93). The intestinal, finger ulcer and breathing S-HAQ VASs were able to differentiate patients according to their respective organ involvement. As hypothesized, the S-HAQ correlated better with the Physical Summary Component (PCS) than the Mental Summary Component (MCS) scores of the SF36v2. The SSc-QoL also demonstrated good convergent validity with the SF36v2 scales.


CONCLUSIONS
In this pilot study, we provided preliminary evidence to demonstrate the good test-retest reliability and reasonable construct validity of S-HAQ and SSc-QoL for use in English and Chinese-speaking SSc patients. This forms the basis for future studies to assess more extensively their psychometric properties.
Department of Rheumatology and Immunology, Singapore General Hospital, Singapore.
Xinyi
X
Ng
Julian
J
Thumboo
Andrea H L
AH
Low
D000203:Activities of Daily Living; D044466:Asian People / Q000523:psychology; D032882:Comprehension; D003431:Cross-Cultural Comparison; D004185:Disability Evaluation; D005260:Female; D006304:Health Status; D006305:Health Status Indicators; D006801:Humans; D007802:Language; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D010147:Pain Measurement; D010865:Pilot Projects; D011237:Predictive Value of Tests; D011379:Prognosis; D011594:Psychometrics; D011788:Quality of Life; D015203:Reproducibility of Results; D012595:Scleroderma, Systemic / Q000175:diagnosis* / Q000208:ethnology / Q000503:physiopathology / Q000523:psychology; D012720:Severity of Illness Index; D012846:Singapore / Q000453:epidemiology; D011795:Surveys and Questionnaires