Interobserver variability in transient elastography analysis of patients with chronic hepatitis C
Version of Record online: 14 APR 2014
© 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd
Volume 35, Issue 5, pages 1533–1539, May 2015
How to Cite
Liver Int. 2015; 35: 1533–1539
- Issue online: 15 APR 2015
- Version of Record online: 14 APR 2014
- Accepted manuscript online: 28 MAR 2014 10:50AM EST
- Manuscript Accepted: 23 MAR 2014
- Manuscript Received: 10 DEC 2013
- Fundação Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ)
- HCV ;
Background & Aims
Transient elastography based on liver stiffness measurement is a non-invasive method to assess hepatic fibrosis. However, interobserver variability has led to controversy over its use in fibrosis evaluation. To evaluate the interobserver variation in transient elastography in chronic hepatitis C.
We performed a cross-sectional study, analysing findings from two experienced operators who each assessed 195 patients by transient elastography on the same day. Liver stiffness measurement used to define fibrosis stages, based on METAVIR score, was: <7.1 as F0F1, 7.1–9.4 as F2, 9.5–12.4, as F3 and >12.4 kPa as F4. We also assessed interobserver variation in identification of potential oesophageal varices screening based on transient elastography.
The interobserver intraclass correlation coefficient was 0.940 (95% CI 0.863–0.967) and measurements made by operators correlated [Spearman's ρ = 0.924; P < 0.001]. However, the median liver stiffness measurement assessed by first operators was higher (11.5 vs 9.8 kPa; P < 0.001). The discordance between operators was 35% for at least one stage of fibrosis and 5% for two or more stages. Interobserver reliability values were κ = 0.61 for fibrosis stages F ≥ 2 and κ = 0.80 for cirrhosis. Among the 74 patients determined to have cirrhosis by at least one operator, there was considerable discordance in identification of those with indication for oesophageal varices screening (κ values from 0.13 to 0.61) according to several cut-offs.
Although a high correlation of liver stiffness measurement between operators, interobserver variability in transient elastography was not negligible. This method should not be used as the only screening tool for oesophageal varices in chronic hepatitis C.