Inclusion criteria
1. Original studies of adult patients (≥18 years old) with primary biliary cholangitis, studies reporting generic or disease-specific HRQOL questionnaires as outcome measure.
2. The study had to be a randomized controlled trial, cohort study, case control study, clinical trial, or validation study of HRQL instruments.
3.Articles published between January 1999 and January 2020 (The publication period of 20 years considered for this systematic review is defined based on the reference list from Osborne et al.)[9].