TABLE 3

Sensitivity and Specificity of ^99mTc-TRODAT-1 Binding Ratios and Cutoff Levels for Disease Diagnosis in 3 Age-Specific Groups

Age group (y)	^99mTc-TRODAT-1 binding ratio
Age group (y)		C-S/O	I-S/O	C-C/O	I-C/O	C-P/O	I-P/O	C-P/C	I-P/C
50–59
Cutoff*	0.725	0.832	1.143	1.231	0.542	0.669	0.485	0.540
Sensitivity† (%)	100	100	100	100	100	100	100	91
Specificity‡ (%)	100	100	92.9	71.4	100	100	100	100
60–69
Cutoff*	0.614	0.703	0.957	1.023	0.477	0.585	0.534	0.554
Sensitivity† (%)	100	100	97.6	95.5	100	100	100	100
Specificity‡ (%)	100	100	100	92.9	100	100	100	100
70–79
Cutoff*	0.513	0.613	0.799	0.881	0.379	0.504	0.513	0.547
Sensitivity† (%)	100	100	95	95	100	100	100	100
Specificity‡ (%)	100	100	100	100	100	100	100	90
Total
Cutoff*	0.595	0.630	0.953	0.955	0.470	0.509	0.526	0.547
Sensitivity† (%)	98.6	94.4	91.7	87.5	100	95.8	100	97.2
Specificity‡ (%)	100	100	92.1	92.1	100	100	100	97.4

↵* Cutoff means binding ratios that have the maximal probability of correctly assigning patients and controls to their respective groups. All cutoff values are averages of 2 consecutively ordered, observed test values.
↵^† True-positive rate.
↵^‡ One minus the false-positive rate.
Abbreviations are as defined in Table 2.