Development and initial validation of the chronic hepatitis B quality of life instrument (CHBQOL) among Chinese patients

Purpose This study developed and tested preliminary measurement properties of a Chinese scale specifically designed to measure HRQOL in patients with chronic hepatitis B (CHBQOL). Methods We conducted 94 individual interviews with CHB patients to solicit items and five hepatitis expert interviews along with three rounds of cognitive interviews to identify problems with relevance and understanding of content. A cross-sectional validation study was then conducted to evaluate measurement properties (n = 578). Factor analysis was used to determine the latent structure of the scale. Reliability was evaluated through Cronbach's alpha coefficients and intra-class correlation coefficients (ICCs). Measurement model adequacy, convergent, discriminant, and known-groups validity were also examined. Results A scale of 30 items was drafted. After item reduction, the remaining 23 items were assigned to the CHBQOL Somatic symptoms, Emotional symptoms, Belief and Social stigma domains, which had acceptable goodness of fit (chi(2)/df = 3.13, GFI = 0.90, AGFI = 0.88, RMSEA = 0.06, SRMR = 0.05). All the CHBQOL domains had satisfactory reliability with Cronbach's alpha coefficients ranging from 0.73 to 0.91 and ICCs were higher than 0.70 except for Belief domain (ICC = 0.54). Convergent and discriminant validity were acceptable as supported by significant item-domain correlations (0.64-0.90). In general, the correlations between CHBQOL and the SF-36 dimensions met hypotheses. Significant differences were found by mean scores in the subgroups of demographic and clinical variables, supporting the known-groups validity. Conclusions The CHBQOL instrument proved to be an appropriate tool for assessing HRQOL among Chinese CHB patients.