TABLE 6

Features with Their Sphere S₃₇–S₁₇ COVs (Mean ± SD), Optimal Voxel Size, Optimal Bin Size, and Resultant Optimized COV Across Imaging Systems

Feature	Feature category	COV (%)	Voxel size	Bin size	COV (%)
Information correlation	GLCM	0.0 ± 0.0^*	4	0.01	0.0^*
Compactness	Shape	0.6 ± 0.3^*	1	NA	0.2^*
Small zone size emphasis	GLZSM	12.3 ± 8.4^‡	4	0.01	2.0^*
Entropy	GLCM	6.9 ± 3.0^†	4	0.01	2.1^*
Zone size percentage	GLZSM	31.3 ± 27.5	4	0.01	3.6^*
Sum entropy	GLCM	5.6 ± 1.3^†	4	0.01	3.7^*
Large zone size emphasis	GLZSM	100.3 ± 75.4	4	0.01	4.9^*
Difference entropy	GLCM	11.7 ± 3.6^‡	4	0.01	6.5^†
Spheric dice coefficient	Shape	7.9 ± 1.4^†	2	NA	6.8^†
Coarseness	NGTDM	11.2 ± 4.7^‡	1	0.01	7.45^†
Correlation	GLCM	13.1 ± 0.1^‡	1	0.1	12.9^‡
Inverse difference	GLCM	21.3 ± 3.1	1	0.1	14.9^‡
Angular second moment	GLCM	56.5 ± 17.7	4	0.01	17.6^‡
Inverse difference moment	GLCM	29.8 ± 3.8	1	0.1	20.6
Volume	Shape	22.8 ± 0.5	4	NA	22.0
Sum average	GLCM	26.4 ± 0.7	2	0.01	25.3
Low gray-level zone emphasis	GLZSM	49.7 ± 28.5	4	0.01	26.9
Small zone low gray emphasis	GLZSM	48.6 ± 30.5	4	0.01	27.8
Busyness	NGTDM	60.5 ± 16.8	4	0.01	27.9
Gray-level nonuniformity	GLZSM	41.7 ± 3.9	4	0.01	28.7
Contrast	NGTDM	51.9 ± 12	1	0.1	29.0
Texture strength	NGTDM	43.9 ± 8.2	4	0.01	30.0
Dissimilarity	GLCM	31.4 ± 0.5	4	0.01	30.7
Large zone low gray emphasis	GLZSM	135.3 ± 75.4	4	0.01	30.8
Maximum probability	GLCM	52.4 ± 11	4	0.01	33.4
High gray-level zone emphasis	GLZSM	41.7 ± 3.9	1	0.05	35.6
Zone size nonuniformity	GLZSM	62.7 ± 17	4	0.01	38.3
Large zone high gray emphasis	GLZSM	76.6 ± 52	4	0.01	45.0
Auto correlation	GLCM	47.1 ± 0.8	2	0.01	45.7
Sum-of-squares variance	GLCM	47.7 ± 1.2	2	0.01	46.1
Sum variance	GLCM	47.9 ± 0.7	4	0.01	46.9
Small zone high gray emphasis	GLZSM	50.3 ± 7.8	4	0.01	47.4
Difference variance	GLCM	57.9 ± 1.3	1	0.1	54.0
Complexity	NGTDM	64.6 ± 4.8	4	0.01	55.1
Contrast	GLCM	57.1 ± 0.5	4	0.01	56.4
Cluster shade	GLCM	82.5 ± 4.7	1	0.01	76.9
Cluster prominence	GLCM	86.6 ± 1.2	4	0.01	84.7

↵* COV < 5%.
↵† 5% ≤ COV < 10%.
↵‡ 10% ≤ COV < 20%.
NA = not applicable.
COVs without footnotes are ≥20%. List is sorted by increasing optimized COV.