Reliability And Validity Assessment Of The Chinese Version Of The Autoimmune Bullous Disease Quality Of Life Questionnaire

Background: Autoimmune bullous disease(AIBD)is a group of skin diseases which affect the skin and mucous membrane of the patients,including pemphigus vulgaris(PV),pemphigus foliaceus(PF),paraneoplastic pemphigus(PNP),bullous pemphigoid(BP),epidermolysis bullosa acquisita(EBA),linear Ig A bullous dermatosis(LABD),pemphigoid gestationis(PG)and dermatitis herpetiformis(DH).Clinical manifestations of AIBD include erythema,bulla and erosions.Patients with AIBD may have itch,pain and infection.AIBD can be life-threatening.Treatment of AIBD with glucocorticoid can lead to hypertension,high blood sugar,osteoporosis and other side effects which severely impinge on the patient's quality of life(QOL).QOL assessment becomes increasingly important because a measure of QOL provides a suitable means to monitor disease activity and to evaluate the effectiveness of care in randomized clinical trials.QOL assessment provides evidences for choosing an optimized scheme for the patients in the treatment.High quality QOL assessment may be used to compare the results of randomized controlled trials and apply in Meta-analysis.Generic instruments and dermatological special instruments are used in the QOL assessment of patients with skin diseases,such as short form 36 health survey questionaire(SF-36)and dermatology life quality index(DLQI).Disease special QOL assessments are the most sensitive instruments,such as psoriasis disability index(PDI).Now there is a lack of a world-wide used questionnaire for AIBD.Recently,Australian researchers developed an Autoimmune Bullous Disease Quality of Life Questionnaire(ABQOL)including 17 questions.Face and content validity were good by expert reviews.The ABQOL was found to have a moderate correlation with scores on the DLQI(R = 0.64)and SF-36(R =-0.51)and low correlation with the Pemphigus Disease Area Index(PDAI)(R = 0.42)and Autoimmune Bullous Disease Skin Disorder Intensity Score(ABSIS)(R = 0.48).In terms of discriminant validity,the ABQOL was found to be more sensitive than the DLQI(P<0.02)and SF-36(P<0.01).The ABQOL was also found to be a reliable instrument evaluated by internal consistency(Cronbach's alpha =0.84).The test-retest reliability(ICC=0.92)indicated that the ABQOL will yield consistent results from patients under similar conditions.Future work should include incorporating patient weighting on questions to further increase content validity and translation of the measure to other languages.Objective: To translate and develop the Chinese version of the ABQOL from the English version and determine the validity and reliability of the Chinese version of the ABQOL in Chinese patients with AIBD.Methods: Having gotten the authorization of the original authors,we translated and culture adapted the English version of ABQOL to develop the Chinese version of the ABQOL.Then using the Chinese version of ABQOL,DLQI and SF-36,we investigated 101 patients with AIBD in the in-patient and out-patient departments.Some of the patients performed the second survey in one week.The data was analyzed by SPSS 10.01.The reliability analysis included Cronbach's alpha coefficient and test-retest reliability.The validity analysis included content validity,construct validity,convergent validity and discriminant validity.Results: 1.One hundred and one patients with AIBD were enrolled in the ABQOL survey.The average age of the patients was 50.02 years old.The ratio of man and women was 67:34.The average course of AIBD was 17.82 months.2.The results from the survey of 101 AIBD patients indicated that Cronbathe's alpha was 0.879,showing that the ABQOL has a high inner consistency.3.The results from 61 patients who finished the second survey indicated that the intra-class correlation coefficient(ICC)was 0.867.The ICC result indicates that the ABQOL will yield consistent results from patients under similar conditions.The Chinese version of ABQOL has good test-retest reliability.4.The Chinese version of ABQOL has good content validity [the item-level CVI(I-CVI)=1,scale-level CVI(S-CVI)=1].5.The result from 101 patients indicated that the Chinese version of ABQOL have a good construct validity.Five common factors extracted by the factor analysis can explain 66.459% of the overall variation.Each item has a good weigh in the correspondent factor(>0.4).The score of the Chinese version of ABQOL and DLQI showed a moderate correlation(R= 0.770,P<0.01).The score of the Chinese version of ABQOL and SF-36 showed a negative moderate correlation(R=-0.623,P<0.001).With regard to discriminant validity,there was no significant difference between the proportions of insensitive items in ABQOL and SF-36 according to the Pearson Chi-square test(P=0.823).There was no significant difference between the proportions of insensitive items in ABQOL and and DLQI in terms of discriminant validity(Fisher exact test,P=0.236).Conclusions: The Chinese version of the ABQOL has a good reliability and validity and could be used as a tool in the evaluation of the QOL in Chinese patients with AIBD.