Liver biochemistry abnormality or injury (LBAI) and acute liver injury (ALI)
COVID-19-related liver injury was divided into three stages as per the Chinese Guideline for COVID-19-related liver injury12. Stage 0, normal liver biochemistry (LB), was defined as markers indicating liver function i.e. ALT, AST, TBIL within normal limits. Stage 1, liver biochemistry abnormality (LBA), was defined as liver function markers outside the normal limits but not reaching the thresholds for stage 2. Stage 2, ALI, was defined as an ALT or AST increase of ≥3 times the upper limit of normal, or TBIL increase of ≥2 times the upper limit of normal. In our study, LBAI was defined as either stage 1 or stage 2. Worsening of LB was defined as any stage elevation during hospitalization. Cases were excluded from the study if no data on ALT, AST and total bilirubin (TBIL) were available.