TABLE 2. Sensitivity of Molecular Breast Imaging as a Function of Tumor Size and Detector Heads Viewed During Blinded Review by Three Readers.

Tumor Diameter (mm)	No. of Tumors	Detector Head(s) Used	Reader 1			Reader 2			Reader 3			Average Sensitivity (%)	p
			No. of Tumors		Sensitivity (%)	No. of Tumors		Sensitivity (%)	No. of Tumors		Sensitivity (%)
			TP	FN		TP	FN		TP	FN
0–5	16	Single	7	9	44	7	9	44	7	9	44	44	0.130
		Dual	11	5	69	11	5	69	10	6	63	67
6–10	45	Single	31	14	69	39	6	87	33	12	73	76	0.060
		Dual	41	4	91	41	4	91	36	9	80	87
11–15	30	Single	28	2	93	29	1	97	28	2	93	94	1.00
		Dual	29	1	97	29	1	97	29	1	97	97
16–20	19	Single	16	3	84	16	3	84	16	3	84	84	0.50
		Dual	18	1	95	18	1	95	18	1	95	95
> 20	18	Single	16	2	89	17	1	94	17	1	94	92	1.00
		Dual	18	0	100	18	0	100	18	0	100	100
All tumors ≤ 10	61	Single	38	23	62	46	15	75	40	21	66	68	0.004
		Dual	52	9	85	52	9	85	46	15	75	82
All tumors	128	Single	98	30	77	108	20	84	101	27	79	80	< 0.0005
		Dual	117	11	91	117	11	91	111	17	87	90

Note—Difference in the average sensitivity of dual-head molecular breast imaging compared with single-head molecular breast imaging was statistically significant using the McNemar test. Boldface indicates statistical significance. TP = true-positive, FN = false-negative.