Assessing the Reliability of a Semiautomated Segmentation Algorithm for Quantifying Erosions in the Metacarpophalangeal Joints of Patients with Rheumatoid Arthritis.

OBJECTIVE: Assess the reliability of early erosions in rheumatoid arthritis (EERA) software for quantifying erosive damage to the metacarpophalangeal joints of patients with rheumatoid arthritis (RA). METHODS: One hundred magnetic resonance image sets from 68 patients with early referral RA were evaluated. Reliability was assessed using 95% limits of agreement and intraclass correlation coefficient (ICC) with 95% CI. RESULTS: Limits of agreement linearly depended on erosion volume: 0.44× between readers and 0.19× within readers. Interrater ICC was 0.976 (95% CI 0.965-0.984) and intrarater ICC was 0.996 (95% CI 0.994-0.997). CONCLUSION: EERA is highly reproducible for quantifying erosions in patients with early RA.