Controlled attenuation parameter for the detection of steatosis severity in chronic liver disease: A meta-analysis of diagnostic accuracy

Background and AimControlled attenuation parameter (CAP) is a novel ultrasound-based elastography method for detection of steatosis severity. This meta-analysis aimed to assess the performance of CAP. MethodsPubMed, the Cochrane Library, and the Web of Knowledge were searched to find studies, published in English, relating to accuracy evaluations of CAP for detecting stage 1 (S1), stage 2 (S2), or stage 3 (S3) hepatic steatosis which was diagnosed by liver biopsy. Sensitivities, specificities, and hierarchical summary receiver operating characteristic (HSROC) curves were used to examine CAP performance. The clinical utility of CAP was also evaluated. ResultsNine studies, with 11 cohorts were analyzed. The summary sensitivities and specificities values were 0.78 (95% confidence interval [CI], 0.69-0.84) and 0.79 (95% CI, 0.68-0.86) for S1, 0.85 (95% CI, 0.74-0.92) and 0.79 (95% CI, 0.71-0.85) for S2, and 0.83 (95% CI, 0.76-0.89) and 0.79 (95% CI, 0.68-0.87) for S3. The HSROCs were 0.85 (95% CI, 0.81-88) for S1, 0.88 (95% CI, 0.85-0.91) for S2, and 0.87 (95% CI, 0.84-0.90) for S3. Following a positive measurement (over the threshold value) for S1, S2, and S3, the corresponding post-test probabilities for the presence of steatosis (pretest probability was 50%) were 78%, 80% and 80%, respectively; if the values were below these thresholds (negative results), the post-test probabilities were 22%, 16%, and 17%, respectively. ConclusionsCAP has good sensitivity and specificity for detecting hepatic steatosis; however, based on a meta-analysis, CAP was limited in their accuracy of steatosis, which precluded widespread use in clinical practice.