Differentiating Small (≤1 cm) Focal Liver Lesions as Metastases or Cysts by means of Computed Tomography: A Case-Study to Illustrate a Fuzzy Logic-Based Method to Assess the Impact of Diagnostic Confidence on Radiological Diagnosis

Table 4

2 × 2 tables built on reader R1 (Table 3(a)) and reader R2 (Table 3(b)) diagnoses, based on the matching with the standard of reference. Cells show the algebraic sum of fuzzy diagnostic confidence (DC) levels entered by readers for each diagnosis. Numbers in parenthesis represent the classical crisp diagnoses based on the binary logic. Of note, lines showing P(d) (i.e., DC in diagnosis of metastasis) and N(d) (i.e., DC in a diagnosis of cyst) values are complementary, since N(d) = 1 − P(d). R1 = reader 1; R2 = reader 2.

(a)

R1	Standard of reference		Total
	Metastases	Cysts
P(d)	27 (27)	0.2 (0)	27.2 (27)
N(d)	3 (3)	19.8 (20)	22.8 (23)
Total	30 (30)	20 (20)	50

(b)

R2	Standard of reference		Total
	Metastases	Cysts
P(d)	28.2 (28)	2.4 (1)	30.6 (29)
N(d)	1.8 (2)	17.6 (19)	19.4 (21)
Total	30 (30)	20 (20)	50