Table 2

Decision tree classification of the prostate training and test sets

SampleNormalBPHPCAMisclassified rate
A. Training set
HM (N = 82)78 (95.12%)0 (0.00%)4 (4.88%)4 (4.88%)
BPH (N = 77)0 (0.00%)72 (93.51%)5 (6.49%)5 (6.49%)
PCA stage T1, T2 (N = 84)2 (2.38%)0 (0.00%)82 (97.61%)2 (2.38%)
PCA, stage T3, T4 (N = 83)2 (2.40%)0 (0.00%)81 (97.59%)2 (2.41%)
Total no. of samples (N = 326)13 (3.99%)
SampleNormalBPHPCAMisclassified rate
B. Test set
HM (N = 15)15 (100.00%)0 (0.00%)0 (0.00%)0 (0.00%)
BPH (N = 15)0 (0.00%)14 (93.33%)1 (6.67%)1 (6.67%)
PCA, stage T1, T2 (N = 15)3 (6.67%)0 (0.00%)12 (80.00%)3 (20.00%)
PCA, stage T3, T4 (N = 15)1 (6.67%)1 (6.67%)13 (86.67%)2 (13.33%)
Total no. of samples (N = 60)6 (10.00%)
Disease/nondiseasePercent positive (no. positive/no. tested)
PCA/HMPCA/BPHPCA/(BPH/HM)BPH/HMBPH/T1,T2Ti,T2/T3,T4
C. Differentiation of prostate disease from nondisease in the blinded test set
Sensitivity83 (25/30)83 (25/30)83 (25/30)93 (14/15)93 (14/15)80 (12/15)
Specificity100 (15/15)93 (14/15)97 (29/30)100 (15/15)80 (12/15)87 (13/15)