Table 1.

Summary of radiologist interrater agreement in categorical assessment of COVID-19 lung disease severity on chest radiographs

Radiologist User Cohort	κ Without Using AI System (95% CI)	κ Using AI System (95% CI)
PXS-original (four radiologists) 2 Thoracic radiologists 2 Emergency radiologists	0.40 (0.34–0.46) 0.51 (0.39–0.61) 0.25 (0.12–0.36)	0.66 (0.59–0.72) 0.75 (0.66–0.83) 0.60 (0.48–0.70)
PXS-updated (three thoracic radiologists)	n/a	0.74 (0.68–0.81)

κ, kappa (Fleiss or Cohen where appropriate), n/a, not assessed. Bootstrap 95% confidence intervals (CI) are shown for each κ in parentheses.