TABLE IV.

Cartilage surface positioning errors (in mm) achieved by hierarchical classifier, gradient cost and single-stage RF classifier using 3D LOGISMOS algorithm. Paired t-test comparisons are reported for (NAF+RF vs. Gradient) and (NAF+RF vs. RF only)

n=108	NAF+RF	Gradient	p-value	RF only	p-value
Femur signed	−0.01±0.18	−0.31±0.24	≪ 0.001	−0.10±0.17	≪ 0.001
Femur unsigned	0.55±0.11	0.69±0.13	≪ 0.001	0.56±0.10	≪ 0.001
cMF signed	−0.04±0.29	−0.38±0.58	≪ 0.001	−0.11±0.27	≪ 0.001
cMF unsigned	0.52±0.16	0.78±0.35	≪ 0.001	0.55±0.17	≪ 0.001
cLF signed	−0.26±0.24	−0.52±0.35	≪ 0.001	−0.36±0.20	≪ 0.001
cLF unsigned	0.42±0.12	0.65±0.20	≪ 0.001	0.47±0.11	≪ 0.001
Tibia signed	0.06±0.17	−0.11±0.35	≪ 0.001	0.11±0.22	≪ 0.001
Tibia unsigned	0.60±0.14	0.79±0.20	≪ 0.001	0.62±0.18	≪ 0.001
cMT signed	−0.15±0.31	−0.25±0.77	0.193	−0.09±0.34	0.003
cMT unsigned	0.52±0.20	0.92±0.41	≪ 0.001	0.58±0.22	≪ 0.001
cLT signed	−0.03±0.32	0.36±1.12	≪ 0.001	−0.01±0.32	0.16
cLT unsigned	0.46±0.17	0.79±0.99	≪ 0.001	0.47±0.18	0.31

^*Bold indicates statistically significant reduction in positioning errors.