Association between Hoehn and Yahr, Mini-Mental State Examination, age, and clinical syndrome predominance and diagnostic effectiveness of ioflupane I 123 injection (DaTSCANTM) in subjects with clinically uncertain parkinsonian syndromes

Table 5 Efficacy parameters for prediction of ioflupane [ ¹²³ I] imaging, 1 year post scan: clinical syndrome predominance ( n = 92)

Subjects with CUPS	Clinical diagnosis at 1 year post-scan
	Subgroup A: BRP dominant^a			Subgroup B: TD^b			Subgroup C: balanced^c
	PS	Non-PS	Total	PS	Non-PS	Total	PS	Non-PS	Total
Abnormal ioflupane [ ¹²³ I] images ^d	17	2	19	10	0	10	19	0	19
Normal ioflupane [ ¹²³ I] images	2	4	6	0	25	25	1	12	13
Total	19	6	25	10	25	35	20	12	32
Statistic	Result	Exact 95% CI	P value ^e (subgroup A vs. subgroup B)	Result	Exact 95% CI	P value ^e (subgroup B vs. subgroup C)	Result	Exact 95% CI	P value ^e (subgroup C vs. subgroup A)
Sensitivity ^f	0.8947	(0.6686, 0.9870)	0.5320	1.0000	(0.6915, 1.0000)	1.0000	0.9500	(0.7513, 0.9987)	0.6050
Specificity ^g	0.6667	(0.2228, 0.9567)	0.0323	1.0000	(0.8628, 1.0000)	NE	1.0000	(0.7354, 1.0000)	0.0980
Accuracy	0.8400	(0.6392, 0.9546)	0.0259	1.0000	(0.9000, 1.0000)	0.4776	0.9688	(0.8378, 0.9992)	0.1575
Positive predictive value	0.8947	(0.6686, 0.9870)	0.5320	1.0000	(0.6915, 1.0000)	NE	1.0000	(0.8235, 1.0000)	0.4865
Negative predictive value	0.6667	(0.2228, 0.9567)	0.0323	1.0000	(0.8628, 1.0000)	0.3421	0.9231	0.6397, 0.9981)	0.2219

BRP, bradykinesia, rigidity, postural instability; CI, confidence interval; CUPS, clinically uncertain parkinsonian syndrome; NE, not estimable; PS: Parkinsonian syndrome; TD, tremor dominant. ^aMaximal score of bradykinesia, rigidity, or postural instability > tremor score. ^bTremor score > maximal score of bradykinesia, rigidity, or postural instability. ^cMaximal score of bradykinesia, rigidity, or postural instability = tremor score. ^dAbnormal imaging types 1, 2 and 3. ^e P value is based on Fisher’s exact test. ^fSensitivity is equivalent to positive percent agreement. ^gSpecificity is equivalent to negative percent agreement.

ISSN: 1758-9193