Twenty-two studies (n=4,760 patients) were included in the review. The median sample size was 97 patients (range 30 to 1,007). Nineteen studies enrolled patients consecutively, although in one further study, recruitment of patients took place from the cohort. The liver biopsies were obtained blinded to transient elastography, but the results of transient elastography were not explicitly reported to have been obtained blind to liver biopsies.
Diagnostic cut-off levels: The weighted mean kilopascal of significant liver fibrosis (up to F2) was 7.81 (95% CI 7.77 to 7.85; n=3,514 patients) and liver cirrhosis (F4) was 15.56 (95% CI 15.50 to 15.70; n=4,430 patients) in studies that reported cut-offs (22 studies).
Liver fibrosis diagnosis (up to F2): In 17 studies that provided diagnostic accuracy data of transient elastography, the pooled sensitivity of the kilopascal score for significant liver fibrosis was 71.9% (95% CI 71.4 to 72.4; n=3,066 patients) and the specificity of the score was 82.4% (95% CI 81.9 to 82.9; n=3,066 patients). The kilopascal score for significant fibrosis was 7.71 (95% CI 7.67 to 7.75).
Liver cirrhosis diagnosis (F4): In studies that evaluated diagnostic test data of liver stiffness measurements by transient elastography for liver cirrhosis, the sensitivity was 84.45% (95% CI 84.2 to 84.7; n=4,052 patients) and the specificity was 94.69 (95% CI 94.3 to 95.0; n=4,052 patients). The kilopascal score of 15.08 (95% CI 15.0 to 15.10).