Improvement of Transient Elastography Applicability and Diagnostic Accuracy to Identify Significant Fibrosis by Experienced Operators Using the M and XL Probe.

Study Overview
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Brief Summary
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Transient elastography (TE)is the reference method to identify liver stiffness (LSM) but fails to obtain a measurement in 3% of cases and results are considered unreliable in 16%. The aim of this study is to evaluate the applicability and diagnostic accuracy of TE performed by trained operators (<500 explorations), after a second evaluation by experienced explorers (>500 explorations) and after a third exploration using XL probe. Inadequate LSM will be re-evaluated by experienced operators with the M (standard size) probe. A third register will be performed with XL (obese size) probe in those patients with inadequate M probe determination. Diagnostic accuracy will be estimated in patients with liver biopsy to identify significant fibrosis with a TE cut-off value of 7.6 kPa (kilo pascal).

Official Title
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Improvement of Transient Elastography Applicability and Diagnostic Accuracy to Identify Significant Fibrosis by Experienced Operators Using the M and XL Probe.

Conditions
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Chronic Liver Diseases (CLD)

Intervention / Treatment
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* Device: Trained operator with M probe.
* Device: Experienced operator with M probe.
* Device: Experienced operator with XL probe.


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients with chronic liver disease evaluated with TE by trained operators (experience <500 explorations). Signed inform consent. Aged between 18-90. Exclusion Criteria: Patients with ascites. Pregnancy.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 90 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Patients with chronic liver disease<br> | Device: Trained operator with M probe.<br>* Trained operator with M probe: non-drug intervention, baseline comparator.<br>Device: Experienced operator with M probe.<br>* Experienced operator with M probe: non-drug intervention, longitudinal comparator.<br>Device: Experienced operator with XL probe.<br>* Experienced operator with XL probe: non-drug intervention, longitudinal comparator.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Applicability of transient elastography (TE) | Applicability will be calculated as the proportion of reliable liver stiffness measurements (LSM). TE will be considered ADEQUATE when it included at least 10 valid measurements with a success rate ≥60% and interquartile range/median of LSM (IQR/M) ≤30% OR INADEQUATE. | Will be calculated after evaluation of all included patients with M probe by trained operators (at baseline and after 48 weeks), M probe by experienced operators after 72 weeks and XL probe after 72 weeks. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Diagnostic accuracy of TE | Diagnostic accuracy will be calculated with the number of correctly classified patients (wuth significant fibrosis) considering a cut-off value of 7.6 kPa. | Will be calculated after evaluation of all included patients with M probe by trained operators after 48 weeks, M probe by experienced operators after 72 weeks and XL probe after 72 weeks. |