Accurate and generalizable quantitative scoring of liver steatosis from ultrasound images via scalable deep learning

Table 3 Receiver operating characteristic analysis on the histopathology unblinded test group and histopathology blinded test group cohorts for diagnosing steatosis grades

	HP-U					HP-T
View	n	AUC ≥ 5%	AUC ≥ 33%	AUC ≥ 66%	Acc	n	AUC ≥ 5%	AUC ≥ 33%	AUC ≥ 66%	Acc
Complete 4 view group study1
LLL	41	0.98 (0.93, 1.00)	0.95 (0.89, 1.00)	0.94 (0.87, 1.00)	83%	51	0.90 (0.82, 0.98)	0.92 (0.81, 1.00)	0.90 (0.82, 0.99)	88%
RLL	41	0.96 (0.90, 1.00)	0.95 (0.89, 1.00)	0.89 (0.79, 0.99)	85%	51	0.84 (0.73, 0.95)	0.93 (0.84, 1.00)	0.92 (0.85, 1.00)	96%
LKC	41	0.96 (0.90, 1.00)	0.95 (0.89, 1.00)	0.93 (0.84, 1.00)	83%	51	0.84 (0.73, 0.95)	0.95 (0.90, 1.00)	0.88 (0.79, 0.97)	90%
SC	41	0.96 (0.90, 1.00)	0.92 (0.84, 1.00)	0.89 (0.79, 0.99)	83%	51	0.88 (0.79, 0.97)	0.93 (0.86, 1.00)	0.88 (0.77, 0.99)	90%
All view groups	41	0.96 (0.90, 1.00)	0.94 (0.88, 1.00)	0.92 (0.83, 1.00)	83%	51	0.88 (0.79, 0.98)	0.95 (0.88, 1.00)	0.91 (0.83, 0.99)	94%
Individual view group study1
LLL	103	0.95 (0.90, 0.99)	0.93 (0.87, 0.98)	0.91 (0.86, 0.97)	80%	96	0.84 (0.76, 0.93)	0.92 (0.85, 0.99)	0.93 (0.88, 0.98)	90%
RLL	138	0.94 (0.91, 0.98)	0.91 (0.86, 0.98)	0.85 (0.78, 0.92)	83%	109	0.82 (0.74, 0.90)	0.89 (0.83, 0.96)	0.92 (0.87, 0.97)	92%
LKC	88	0.96 (0.92, 1.00)	0.92 (0.86, 0.98)	0.84 (0.76, 0.92)	80%	71	0.81 (0.69, 0.93)	0.93 (0.87, 0.99)	0.89 (0.81, 0.96)	90%
SC	117	0.93 (0.89, 0.98)	0.91 (0.85, 0.96)	0.86 (0.79, 0.92)	79%	90	0.86 (0.77, 0.94)	0.89 (0.82, 0.96)	0.90 (0.83, 0.97)	88%
All view groups	147	0.95 (0.91, 0.98)	0.92 (0.88, 0.96)	0.87 (0.81, 0.92)	76%	112	0.85 (0.77, 0.93)	0.91 (0.85, 0.97)	0.93 (0.88, 0.98)	90%
FibroScan comparison study1,2
All view groups	147	0.953 (0.92, 0.98)	0.953 (0.92, 0.98)	0.923 (0.88, 0.97)	77%	80	0.93 (0.87, 0.98)	0.97 (0.93, 1.00)	0.923 (0.86, 0.98)	91%
FibroScan	147	0.88 (0.81, 0.95)	0.88 (0.81, 0.95)	0.80 (0.73, 0.87)	62%	80	0.89 (0.82, 0.96)	0.92 (0.86, 0.98)	0.82 (0.73, 0.92)	68%

¹Filtered with a minimum of 3 images for each view group.

²Selecting only studies with associated FibroScan control attenuation parameter (CAP) scores.

³Area under the curve of the receiver operating characteristic significantly better than FibroScan CAP scores.

“Complete 4 view groups study” only selects studies where every view group is qualifying (three or more images), whereas “Individual view group study” examines the performance of each qualifying view group individually. Numbers in parentheses are 95% confidence intervals. All trends between the deep learning/CAP score and the histopathology grades were significant (P < 0.001). “Acc” is the classification accuracy when the threshold values calculated by optimizing the Youden index[44] are applied. LLL: Left liver lobe; RLL: Right liver lobe; LKC: Liver/kidney contrast; SC: Subcostal; HP-U: Histopathology unblinded test group; HP-T: Histopathology blinded test group; AUC: Area under the curve.