Hugo Perazzo1, Flavia F Fernandes2, João Carlos Soares3, Juliana Fittipaldi3, Sandra W Cardoso3, Beatriz Grinsztejn3, Valdiléa G Veloso3. 1. National Institute of Infectious Disease - Fundação Oswaldo Cruz, Laboratory of clinical research on STD/AIDS, Rio de Janeiro, Brazil. Electronic address: hugo.perazzo@ini.fiocruz.br. 2. Bonsucesso Federal Hospital, Gastroenterology Department, Rio de Janeiro, Brazil. 3. National Institute of Infectious Disease - Fundação Oswaldo Cruz, Laboratory of clinical research on STD/AIDS, Rio de Janeiro, Brazil.
Abstract
BACKGROUND AND OBJECTIVES: Liver stiffness measurement (LSM) by transient elastography has been validated as a noninvasive method to stage liver fibrosis. Few studies have evaluated the learning curve of this method and its reproducibility has led to controversy results. We aimed to evaluate the intra- and interobserver agreement of transient elastography as well as its learning curve for definition of an experimented operator. METHODS: We retrospectively analyzed 922 examinations performed in 544 patients during a training program of transient elastography. Patients with chronic hepatitis C with or without HIV co-infection that had two examinations by the training operator (intraobserver analysis; n=125) or examination by both training and experimented operators (interobserver analysis; n=151) in the same day were included. LSM was converted to METAVIR score: <7.1 as F0F1, 7.1-9.4 as F2, 9.5-12.4, as F3 and >12.4 kPa as F4. RESULTS: The overall intra- and interobserver intraclass correlation coefficient [ICC 95% CI] were 0.926 (0.901-0.951) and 0.912 (0.885-0.939), respectively. Measurements were correlated [Spearman's] in intra- [0.906, P<0.0001] and interobserver [0.907, P<0.0001] analysis. Reliability values [kappa (SE)] were k=0.74 (0.09) and k=0.85 (0.08) for fibrosis stages F ≥ 2 and k=0.77 (0.09) and k=0.75 (0.08) for cirrhosis in intra- and interobserver analysis, respectively. Agreement was improved when operator's experience was higher than 100 exams. However, it was observed discordance for fibrosis staging between examinations in a quarter of patients. CONCLUSION: Although there was a considerable discrepancy on fibrosis staging between examinations and a small power, transient elastography had an acceptable reproducibility in our population. Performance of at least 100 examinations should be used to define an experimented operator.
BACKGROUND AND OBJECTIVES:Liver stiffness measurement (LSM) by transient elastography has been validated as a noninvasive method to stage liver fibrosis. Few studies have evaluated the learning curve of this method and its reproducibility has led to controversy results. We aimed to evaluate the intra- and interobserver agreement of transient elastography as well as its learning curve for definition of an experimented operator. METHODS: We retrospectively analyzed 922 examinations performed in 544 patients during a training program of transient elastography. Patients with chronic hepatitis C with or without HIV co-infection that had two examinations by the training operator (intraobserver analysis; n=125) or examination by both training and experimented operators (interobserver analysis; n=151) in the same day were included. LSM was converted to METAVIR score: <7.1 as F0F1, 7.1-9.4 as F2, 9.5-12.4, as F3 and >12.4 kPa as F4. RESULTS: The overall intra- and interobserver intraclass correlation coefficient [ICC 95% CI] were 0.926 (0.901-0.951) and 0.912 (0.885-0.939), respectively. Measurements were correlated [Spearman's] in intra- [0.906, P<0.0001] and interobserver [0.907, P<0.0001] analysis. Reliability values [kappa (SE)] were k=0.74 (0.09) and k=0.85 (0.08) for fibrosis stages F ≥ 2 and k=0.77 (0.09) and k=0.75 (0.08) for cirrhosis in intra- and interobserver analysis, respectively. Agreement was improved when operator's experience was higher than 100 exams. However, it was observed discordance for fibrosis staging between examinations in a quarter of patients. CONCLUSION: Although there was a considerable discrepancy on fibrosis staging between examinations and a small power, transient elastography had an acceptable reproducibility in our population. Performance of at least 100 examinations should be used to define an experimented operator.
Authors: Flavia F Fernandes; Hugo Perazzo; Luiz E Andrade; Alessandra Dellavance; Carlos Terra; Gustavo Pereira; João L Pereira; Frederico Campos; Maria L Ferraz; Renata M Perez Journal: Biomed Res Int Date: 2017-09-13 Impact factor: 3.411
Authors: Saverio Giuseppe Parisi; Monica Basso; Carlo Mengoli; Renzo Scaggiante; Samantha Andreis; Marzia Maria Franzetti; Anna Maria Cattelan; Daniela Zago; Mario Cruciani; Massimo Andreoni; Sara Piovesan; Giorgio Palù; Alfredo Alberti Journal: Ann Gastroenterol Date: 2017-07-04