Skip to main navigation Skip to main content

CMH : Clinical and Molecular Hepatology

OPEN ACCESS
ABOUT
BROWSE ARTICLES
FOR CONTRIBUTORS

Articles

Original Article

Optimal cut-offs of vibration-controlled transient elastography and magnetic resonance elastography in diagnosing advanced liver fibrosis in patients with nonalcoholic fatty liver disease: A systematic review and meta-analysis

Clinical and Molecular Hepatology 2024;30(Suppl):S117-S133.
Published online: August 21, 2024

1Department of Gastroenterology, CHA Bundang Medical Center, CHA University, Seongnam, Korea

2Department of Internal Medicine, Inha University Hospital, Inha University School of Medicine, Incheon, Korea

3Department of Gastroenterology and Hepatology, Hanyang University Guri Hospital, Hanyang University College of Medicine, Guri, Korea

4Department of Internal Medicine, College of Medicine, Bucheon St. Mary’s Hospital, The Catholic University of Korea, Seoul, Korea

5Division of Health Technology Assessment Research, National Evidence-Based Healthcare Collaborating Agency (NECA), Seoul, Korea

6Department of Internal Medicine, Hanyang University Hospital, Hanyang University College of Medicine, Seoul, Korea

7Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Korea

8Yonsei Liver Center, Severance Hospital, Seoul, Korea

9Department of Internal Medicine, College of Medicine, Seoul St. Mary’s Hospital, The Catholic University of Korea, Seoul, Korea

10Department of Internal Medicine, Chung-Ang University College of Medicine, Seoul, Korea

Corresponding author : Seung Up Kim Department of Internal Medicine, Yonsei University College of Medicine, 50-1 Yonsei-ro, Seodaemun-gu, Seoul 03722, Korea Tel: +82-2-2228-1944, Fax: +82-2-393-6884, E-mail: ksukorea@yuhs.ac
Jung Hwan Yu Department of Internal Medicine, Inha University School of Medicine, 27, Inhang-ro, Jung-gu, Incheon 22332, Korea Tel: +82-32-890-3414, Fax: +82-32-863-1333, E-mail: junghwan0081@naver.com

Young Eun Chon and Young-Joo Jin contributed equally as co-first authors.


Editor: Yun Bin Lee, Seoul National University, Korea

• Received: May 24, 2024   • Revised: August 19, 2024   • Accepted: August 20, 2024

Copyright © 2024 by The Korean Association for the Study of the Liver

This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

  • 9,798 Views
  • 218 Download
  • 14 Web of Science
  • 15 Crossref
  • 14 Scopus

Citations

Citations to this article as recorded by  Crossref logo
  • Non-invasive Risk-based Surveillance Strategy for Hepatocellular Carcinoma in Patients with Metabolic Dysfunction-associated Steatotic Liver Disease
    Ji Won Han
    The Korean Journal of Gastroenterology.2026; 86(1): 62.     CrossRef
  • Correspondence to editorial on “Optimal cut-offs of vibration-controlled transient elastography and magnetic resonance elastography in diagnosing advanced liver fibrosis in patients with nonalcoholic fatty liver disease: a systematic review and meta-analy
    Young Eun Chon, Jung Hwan Yu, Seung Up Kim
    Clinical and Molecular Hepatology.2025; 31(1): e61.     CrossRef
  • Essential tools for assessing advanced fibrosis in metabolic dysfunction-associated steatotic liver disease: Editorial on “Optimal cut-offs of vibration-controlled transient elastography and magnetic resonance elastography in diagnosing advanced liver fib
    Won Sohn
    Clinical and Molecular Hepatology.2025; 31(1): 277.     CrossRef
  • Correspondence to editorial on “Optimal cutoffs of vibration-controlled transient elastography and magnetic resonance elastography in diagnosing advanced liver fibrosis in patients with nonalcoholic fatty liver disease: A systematic review and meta-analys
    Jung Hwan Yu, Seung Up Kim
    Clinical and Molecular Hepatology.2025; 31(1): e52.     CrossRef
  • Towards unification of liver stiffness measurement cutoffs: Editorial on “Optimal cut-offs of vibration-controlled transient elastography and magnetic resonance elastography in diagnosing advanced liver fibrosis in patients with nonalcoholic fatty liver d
    Yangyue Zhang, Vincent Wai-Sun Wong
    Clinical and Molecular Hepatology.2025; 31(1): 264.     CrossRef
  • Sustainability of General Population Screening for Steatotic Liver Disease: A Proof-of-Concept Study
    Laura De Rosa, Gabriele Ricco, Maurizia Rossana Brunetto, Ferruccio Bonino, Francesco Faita
    Healthcare.2025; 13(7): 759.     CrossRef
  • Therapeutic Efficacy of Silymarin, Vitamin E, and Essential Phospholipid Combination Therapy on Hepatic Steatosis, Fibrosis, and Metabolic Parameters in MASLD Patients: A Prospective Clinical Study
    Dan-Ionuț Gheonea, Cristina Tocia, Victor-Mihai Sacerdoțianu, Alexandra-Georgiana Bocioagă, Irina-Paula Doica, Nicolae Cătălin Manea, Adina Turcu-Știolică, Carmen-Nicoleta Oancea, Eugen Dumitru
    International Journal of Molecular Sciences.2025; 26(12): 5427.     CrossRef
  • Deep learning radiomics of elastography for diagnosing compensated advanced chronic liver disease: an international multicenter study
    Xue Lu, Haoyan Zhang, Hidekatsu Kuroda, Matteo Garcovich, Victor de Ledinghen, Ivica Grgurević, Runze Linghu, Hong Ding, Jiandong Chang, Min Wu, Cheng Feng, Xinping Ren, Changzhu Liu, Tao Song, Fankun Meng, Yao Zhang, Ye Fang, Sumei Ma, Jinfen Wang, Xiaol
    Visual Computing for Industry, Biomedicine, and Art.2025;[Epub]     CrossRef
  • Liver disease in people with latent autoimmune diabetes in adults (LADA): A cross-sectional study using magnetic resonance elastography
    Ernesto Maddaloni, Marta Zerunian, Vincenzo Cardinale, Annalisa Zurru, Rocco Amendolara, Daniela Luverà, Renata Risi, Luca D’Onofrio, Benedetta Masci, Francesco Covotta, Damiano Caruso, Domenico Alvaro, Andrea Laghi, Raffaella Buzzetti
    Diabetes Research and Clinical Practice.2025; 229: 112465.     CrossRef
  • Paired snRNA-seq and scRNA-seq analysis of MASLD patients to identify early-stage markers for disease progression
    Suebin Park, Su-Hyeon Lee, Se-eun Han, Beom Kyung Kim, Byungjin Hwang
    Hepatology Communications.2025;[Epub]     CrossRef
  • Even Lower Alcohol Intake Might Be Harmful for East Asian Males With MASLD Spectrum
    Byungyoon Yun, Juyeon Oh, Heejoo Park, Jian Lee, Beom Kyung Kim, Jin-Ha Yoon
    Clinical Gastroenterology and Hepatology.2025;[Epub]     CrossRef
  • Lean Metabolic Dysfunction‐Associated Steatotic Liver Disease: A Wolf in Sheep's Clothing
    Xixi Fang, Chenhao Xu, Jun Lu, Runzhou Zhuang, Xiao Xu, Xuyong Wei
    Cell Biochemistry and Function.2025;[Epub]     CrossRef
  • Mistakes in the utilization of vibration-controlled transient elastography in the evaluation of liver fibrosis: a narrative review
    Madunil Anuk Niriella, Uditha Bandara Dassanayake, Charith Priyanga Madurapperuma, Indeewari Prathibha Wijesingha, Arjuna Priyadarshin De Silva, Hithnadura Janaka de Silva
    Expert Review of Gastroenterology & Hepatology.2025; 19(12): 1299.     CrossRef
  • Transient Elastography and Fibroscan: Stethoscope of a Hepatologist in Today’s World
    Sajid Jalil, Mangesh Pagadala, Nicholas Dunn, Hanna Blaney, Mohamed Elfeki, Nimish Thakral, Ashwani K. Singal
    Current Hepatology Reports.2025;[Epub]     CrossRef
  • Comparative analysis of non-invasive fibrosis markers: Insights from chronic HBV, HBV+HDV, and HCV infections
    Aziza Saydullaevna Khikmatullaeva, Krestina Stepanovna Brigida, Nargiza Mirzakhidovna Мirrakhimova, Muazzam Alievna Аbdukadirova, Nargiz Sapievna Ibadullaeva, Allabergan Kadirovich Bayjanov, Nataliya Georgiyevna Kan, Malika Erkinovna Khodjaeva, Nargiza An
    Infectious Medicine.2025; 4(4): 100220.     CrossRef

Download Citation

Download a citation file in RIS format that can be imported by all major citation management software, including EndNote, ProCite, RefWorks, and Reference Manager.

Format:

Include:

Optimal cut-offs of vibration-controlled transient elastography and magnetic resonance elastography in diagnosing advanced liver fibrosis in patients with nonalcoholic fatty liver disease: A systematic review and meta-analysis
Clin Mol Hepatol. 2024;30(Suppl):S117-S133.   Published online August 21, 2024
Download Citation

Download a citation file in RIS format that can be imported by all major citation management software, including EndNote, ProCite, RefWorks, and Reference Manager.

Format:
Include:
Optimal cut-offs of vibration-controlled transient elastography and magnetic resonance elastography in diagnosing advanced liver fibrosis in patients with nonalcoholic fatty liver disease: A systematic review and meta-analysis
Clin Mol Hepatol. 2024;30(Suppl):S117-S133.   Published online August 21, 2024
Close

Figure

  • 0
  • 1
  • 2
  • 3
Optimal cut-offs of vibration-controlled transient elastography and magnetic resonance elastography in diagnosing advanced liver fibrosis in patients with nonalcoholic fatty liver disease: A systematic review and meta-analysis
Image Image Image Image
Figure 1. Flow chart of study selection.
Figure 2. Summary of receiver operating characteristics curves of vibration-controlled transient elastography for assessing fibrosis stages (A) ≥F1, (B) ≥F2, (C) ≥F3, and (D) F4. ROC, receiver operating characteristics; sROC, summary ROC curves; AUC, area under the receiver operating characteristics curve.
Figure 3. Summary of receiver operating characteristics curves of magnetic resonance elastography for assessing fibrosis stages (A) ≥F1, (B) ≥F2, (C) ≥F3, and (D) F4. ROC, receiver operating characteristics; sROC, summary ROC curves; AUC, area under the receiver operating characteristics curve.
Graphical abstract
Optimal cut-offs of vibration-controlled transient elastography and magnetic resonance elastography in diagnosing advanced liver fibrosis in patients with nonalcoholic fatty liver disease: A systematic review and meta-analysis
Author Year Region Study design Patients, n Age, years Male, % BMI, kg/m2 Diabetes mellitus, % Fibrosis stag for analyses
VCTE
Argalia et al. [44] 2022 Italy CS, SS 50 52.2 64 29.4 NR ≥F1, ≥F2, ≥F3, F4
Barsamian et al. [45] 2020 France CS, SS 108 41 21 43 24 ≥F1, ≥F2, ≥F3
Chan et al. [15] 2015 Malaysia CS, SS 101 50.5 54.4 29.3 52.4 ≥F1, ≥F2, ≥F3, F4
Chan et al. [46] 2017 Malaysia, Hongkong CS, SS 57 50.1 49 39.2 NR ≥F1, ≥F2, ≥F3, F4
Gaia et al. [17] 2011 Italy CS, SS 72 48 72.2 27.5 NR ≥F1, ≥F2, ≥F3, F4
Garteiser et al. [47] 2021 France CS, SS 152 42 16 44.1 21 ≥F1, ≥F2
Imajo et al. [48] 2022 Japan CS, SS 231 61 52.7 27.1 61.7 ≥F1, ≥F2, ≥F3, F4
Kim et al. [49] 2022 Korea CS, SS 60 50.9 45.9 29.9 61.7 ≥F1, ≥F2, ≥F3, F4
Kumar et al. [19] 2013 India CS, SS 120 39.1 75 26.1 16.6 ≥F1, ≥F2, ≥F3, F4
Lee et al. [50] 2016 Korea CS, SS 183 40.6 60.7 27.9 14.2 ≥F1, ≥F2, ≥F3, F4
Leong et al. [51] 2020 Malaysia CS, SS 100 57.1 46 30.8 NR ≥F1, ≥F2, ≥F3, F4
Lupsor et al. [21] 2010 Netherlands CS, SS 72 42 70.8 28.7 NR ≥F1, ≥F2, ≥F3
Okajima et al. [52] 2017 Japan CS, SS 163 55.8 48.5 27.2 NR ≥F1, ≥F2, ≥F3
Park et al. [26] 2017 US CS, SS 104 50.8 43.3 30.4 27.9 ≥F1, ≥F2, ≥F3, F4
Sharpton et al. [53] 2021 US CS, SS 114 55 45.6 31.2 NR ≥F1, ≥F2, ≥F3, F4
Shi et al. [54] 2020 China CS, SS 158 48.9 30.4 25.9 26.6 ≥F1, ≥F2, ≥F3, F4
Shima et al. [55] 2020 Japan CS, SS 278 57.8 48.2 27.5 58.6 ≥F1, ≥F3
Siddiqui et al. [56] 2019 US CS, SS 393 51 32 34.4 44 ≥F1, ≥F2, ≥F3, F4
Yang et al. [57] 2021 China CS, SS 91 40 50.5 29.1 71.4 ≥F1, ≥F2, ≥F3, F4
Yoneda et al. [58] 2008 Japan CS, SS 97 51.8 41.2 26.6 NR ≥F1, ≥F2, ≥F3, F4
Boursier et al. [59] 2023 France CS, MS 1,051 58 60 31 49.8 ≥F2, F4
Cardoso et al. [60] 2020 Brazil CS, SS 81 54.2 26 32.8 60 ≥F2
Cassinotto et al. [61] 2016 France CS, MS 291 56.7 59.1 32.1 52.6 ≥F2, ≥F3, F4
Chang et al. [62] 2023 US CS, MS 1,370 56.6 44.5 34.2 38.0 ≥F2, ≥F3, F4
Chang et al. [63] 2019 Singapore CS, MS 51 49.4 55.6 23.9 NR ≥F2, F4
Eddowes et al. [64] 2019 UK CS, MS 373 54 55 33.8 50 ≥F2, ≥F3, F4
Eilenberg et al. [65] 2021 Austria CS, SS 170 42 35.4 44.4 28.2 ≥F2, ≥F3
Ergelen et al. [66] 2015 Turkey CS, SS 87 45.8 49.4 30.6 NR ≥F2, ≥F3
Furlan et al. [16] 2020 US CS, SS 62 50 42 34.8 35 ≥F2
Garg et al. [18] 2018 India CS, SS 76 39.3 23.3 46.2 NR ≥F2, ≥F3
Inadomi et al. [67] 2020 Japan CS, SS 200 59.5 48 28.1 50.3 ≥F2, ≥F3
Jafarov et al. [68] 2020 Turkey CS, SS 139 49 59 32.9 64 ≥F2, ≥F3
Lee et al. [23] 2022 Korea CS, SS 539 56 47.5 26.9 36.2 ≥F2, ≥F3, F4
Lee et al. [69] 2019 Korea CS, SS 184 44.6 69 29.3 37.5 ≥F2
Lee et al. [70] 2022 Korea CS, SS 251 44 52.6 28.6 46.6 ≥F2, ≥F3, F4
Lee et al. [20] 2017 Korea CS, SS 94 55.5 43.6 27.1 39.4 ≥F2, ≥F3, F4
Mendoza et al. [71] 2022 Switzerland CS, SS 104 53.4 58.7 30.9 47.1 ≥F2, ≥F3, F4
Myers et al. [72] 2010 Canada CS, MS 20 NR NR NR NR ≥F2, ≥F3, F4
Myers et al. [73] 2012 Canada CS, MS 276 50 63 30 NR ≥F2, F4
Naveau et al. [24] 2014 France CS, SS 100 42.5 19 41.3 15 ≥F2, ≥F3
Nogami et al. [74] 2022 Japan CS, SS 163 59.7 52.8 28.5 61.3 ≥F2, ≥F3, F4
Oeda et al. [25] 2020 Japan CS, MS 137 NR NR NR NR ≥F2, ≥F3, F4
Ooi et al. [75] 2018 Australia CS, SS 182 44 24.7 45.1 27.1 ≥F2
Petta et al. [27] 2011 Italy CS, SS 146 44.1 71 29.1 14 ≥F2, ≥F3
Taibbi et al. [76] 2021 Italy CS, SS 56 54.7 58.7 29.4 39.1 ≥F2, ≥F3
Vali et al. [77] 2023 Europe CS, MS 632 51.2 58 34.1 42 ≥F2
Wong et al. [78] 2019 France, Hongkong CS, MS 496 54 42.7 30.4 60.5 ≥F2, ≥F3, F4
Wong et al. [30] 2010 France, Hongkong CS, MS 246 51 54.9 28 36.2 ≥F2, ≥F3, F4
Yu et al. [79] 2021 China CS, SS 85 58 40 29.7 100 ≥F2, ≥F3, F4
Petta et al. [28] 2019 Global CS, MS 968 50.1 62.9 29.3 37 ≥F3
Tovo et al. [80] 2019 Brazil CS, MS 104 55.3 26 33 64.4 ≥F3
Kosick et al. [81] 2021 Canada CS, MS 407 48.5 54 32.3 30 ≥F3
Boursier et al. [14] 2016 France CS, MS 452 55.9 60 31.1 46.7 ≥F3
Sanyal et al. [82] 2023 Global CS, MS 1,434 55 50.8 31.7 50.4 ≥F3, F4
Armandi et al. [83] 2023 Turkey LS, SS 96 49.5 62.2 28.4 30.6 ≥F3
Noureddin et al. [84] 2023 US CS, MS 548 58 35 33.3 53 ≥F3, F4
Petta et al. [85] 2017 Global CS, MS 761 50.9 60.2 29.6 54.7 ≥F3
Petta et al. [86] 2015 Italy CS, MS 321 44.7 69.5 28.5 17.8 ≥F3
Anstee et al. [13] 2019 US CS, MS 3,202 58 38 NR 60 ≥F3
Troelstra et al. [87] 2021 Netherlands CS, SS 37 49 62 33.2 43 ≥F3
Seki et al. [88] 2017 Japan CS, SS 171 57.1 50.3 27.7 NR ≥F3
Labenz et al. [89] 2018 Germany CS, MS 261 51 52.5 30.9 29.9 ≥F3
Pavlides et al. [90] 2017 UK CS, SS 71 53.4 43 32.7 35 F4
MRE
Costa-Silva et al. [91] 2018 Brazil CS, SS 49 53.8 14.3 32.2 NR ≥F1, ≥F2, ≥F3, F4
Cui et al. [92] 2016 US CS, SS 125 48.9 45.6 31.8 26 ≥F1, ≥F2, ≥F3, F4
Imajo et al. [93] 2016 Japan CS, SS 142 57.5 57 28.1 71 ≥F1, ≥F2, ≥F3, F4
Imajo et al. [48] 2022 Japan CS, SS 231 61 52.7 27.1 61.7 ≥F1, ≥F2, ≥F3, F4
Kim et al. [94] 2020 Korea CS, SS 47 51 34 28.3 NR ≥F1, ≥F2, ≥F3
Loomba et al. [95] 2014 US CS, SS 117 50.1 43.6 32.4 34.2 ≥F1, ≥F2, ≥F3, F4
Park et al. [26] 2017 US CS, SS 104 50.8 43.3 30.4 27.9 ≥F1, ≥F2, ≥F3, F4
Zhang et al. [96] 2022 US CS, SS 100 51.8 46 31.6 NR ≥F1, ≥F2, ≥F3, F4
Furlan et al. [16] 2020 US CS, SS 62 50 42 34.8 35 ≥F2
Inada et al. [97] 2022 Japan CS, SS 105 65 44.8 27.5 50.5 ≥F2
Nogami et al. [74] 2022 Japan CS, SS 163 55.8 48.5 27.2 NR ≥F2, ≥F3, F4
Troelstra et al. [87] 2021 Netherlands CS, SS 37 49 62 33.2 43 ≥F3
Cui et al. [98] 2015 US CS, SS 102 51.3 58.8 31.7 25.5 ≥F3
Loomba et al. [99] 2016 US CS, SS 100 50.2 44 32.1 33 ≥F3
Cut-off range, kPa Studies, n AUC (95% CI) Sensitivity (95% CI) I2, % (95% CI) Specificity (95% CI) I2, % (95% CI)
VCTE
 ≥F1 5.0–9.6 20 0.83 (0.80–0.86) 0.78 (0.72–0.82) 88.1 (83.9–92.3) 0.75 (0.68–0.81) 83.5 (77.1–89.9)
 ≥F2 4.8–16.4 48 0.83 (0.80–0.86) 0.79 (0.74–0.82) 95.2 (94.5–96.0) 0.74 (0.70–0.78) 92.3 (90.9–93.7)
 ≥F3 7.1–14.1 53 0.87 (0.84–0.90) 0.81 (0.78–0.84) 87.2 (84.6–89.9) 0.79 (0.76–0.82) 90.0 (88.0–91.9)
 F4 6.9–20.1 34 0.94 (0.91–0.96) 0.91 (0.85–0.94) 89.6 (86.8–92.3) 0.87 (0.84–0.89) 92.8 (91.1–94.4)
MRE
 ≥F1 2.5–3.14 8 0.89 (0.86–0.92) 0.78 (0.67–0.86) 84.5 (74.9–94.1) 0.87 (0.74–0.94) 88.1 (81.3–95.0)
 ≥F2 2.77–4.14 11 0.92 (0.89–0.94) 0.85 (0.78–0.90) 79.5 (68.0–91.0) 0.86 (0.78–0.92) 83.3 (74.4-92.2)
 ≥F3 2.3–4.8 12 0.89 (0.86–0.92) 0.85 (0.80–0.88) 0.0 (0.0–87.5) 0.89 (0.85–0.92) 61.8 (37.9-85.8)
 F4 3.35–6.7 8 0.94 (0.91–0.96) 0.88 (0.79–0.93) 0.0 (0.0–96.1) 0.89 (0.83–0.92) 84.1 (74.2-94.0)
Cut-off range, kPa Studies, n Patients, n AUC (95% CI) Sensitivity (95% CI) I2, % (95% CI) Specificity (95% CI) I2, % (95% CI)
VCTE
 7.1–7.9 6 1,895 0.90 (0.87–0.92) 0.89 (0.85–0.91) 35.9 (0.0–94.7) 0.67 (0.59–0.74) 88.8 (81.4–96.3)
 8.0–9.9 33 11,862 0.87 (0.00–1.00) 0.83 (0.80–0.86) 75.0 (66.6–83.4) 0.77 (0.74–0.80) 88.9 (86.0–91.9)
 10.0–11.9 13 2,195 0.87 (0.84–0.90) 0.80 (0.76–0.84) 40.1 (0.9–79.3) 0.84 (0.79–0.88) 77.1 (65.0–89.3)
 12.0–14.1 6 1,256 0.79 (0.75–0.82) 0.55 (0.49–0.61) 25.7 (0.0–90.4) 0.88 (0.84–0.90) 32.5 (0.0–93.7)
MRE
 2.3–2.99 3 241 Cannot be synthesized
 3.62–3.8 5 607 0.94 (0.91–0.96) 0.88 (0.81–0.93) 0.0 (0.0–100.0) 0.91 (0.86–0.94) 64.1 (29.3–98.8)
 3.9–4.8 4 439 0.93 (0.91–0.95) 0.83 (0.73–0.89) 22.2 (0.0–100.0) 0.91 (0.85–0.95) 34.3 (0.0–100.0)
Table 1. Characteristics of the included studies

VCTE, vibration-controlled transient elastography; MRE, magnetic resonance elastography; CS, cross-sectional study; LS, longitudinal study; SS, single center study; MS, multicenter study; BMI, body mass index; NR, not recorded.

Table 2. Pooled diagnostic performance of VCTE and MRE for assessing fibrosis stages in patients with NAFLD

VCTE, vibration-controlled transient elastography; MRE, magnetic resonance elastography; NAFLD, non-alcoholic fatty liver disease; AUC, area under receiver operating characteristics curves; CI, confidence interval.

Table 3. Summary diagnostic performance of VCTE and MRE for detecting advanced fibrosis in patients with NAFLD according to cutoff ranges

VCTE, vibration-controlled transient elastography; MRE, magnetic resonance elastography; NAFLD, non-alcoholic fatty liver disease; AUC, area under receiver operating characteristics curves; CI, confidence interval.