FAST Score Rules Out At-Risk MASH More Accurately Than MRI

Comparing Noninvasive Modalities for Liver Assessment

A systematic review published in the October 2026 issue of the American Journal of Gastroenterology evaluated noninvasive imaging tools for identifying at-risk metabolic dysfunction-associated steatohepatitis (MASH). Shyna Zhuoying Gunalan and colleagues from the National University of Singapore analyzed 20 studies comprising 9,480 total participants.

The review assessed how accurately imaging tools rule in (TRI) or rule out (TRO) at-risk disease. Identifying at-risk MASH early allows clinicians to monitor liver tissue changes before severe fibrotic progression occurs.

Diagnostic Accuracy of the FAST Score

FibroScan-aspartate aminotransferase (FAST) demonstrated the highest sensitivity for ruling out at-risk MASH among all evaluated options. The test achieved a TRO sensitivity of 0.871 alongside a moderate specificity of 0.567.

When used to rule in at-risk MASH, the score showed a specificity of 0.900 and a sensitivity of 0.441. A sensitivity analysis limited to head-to-head comparisons showed that FAST sustained superior diagnostic performance over alternative methods.

Performance of Magnetic Resonance Imaging Techniques

Magnetic resonance elastography (MRE) combined with fibrosis-4 (FIB-4) delivered the second-highest sensitivity for ruling out disease. That combination produced a TRO sensitivity of 0.812 and a specificity of 0.606.

For ruling in at-risk disease, the combination of MRE and FIB-4 reached a specificity of 0.872 with a sensitivity of 0.500. Magnetic resonance imaging (MRI) combined with aspartate aminotransferase (MRI-AST) achieved intermediate accuracy. In contrast, iron-corrected T1 mapping thresholds showed variable diagnostic results across the reviewed cohorts.

Clinical Feasibility and Research Disclosures

The FAST score presents practical operational advantages for clinical practices managing metabolic disease. The authors noted that FAST provides lower testing costs and simpler equipment access than magnetic resonance platforms.

Magnetic resonance tools continue to offer strong diagnostic documentation for patients who require advanced secondary imaging. Several authors involved in the systematic review disclosed financial ties to the biopharmaceutical sector.