RSNA and BSTI grading systems of COVID-19 pneumonia: comparison of the diagnostic performance and interobserver agreement

Table 4 Comparison of patients' classification of two observers in terms of COVID-19 according to BSTI guidance statement and RSNA expert consensus statement

RT-PCR observer A				RSNA expert consensus statement			Test Value X²; p
RT-PCR observer A				Typical	Indeterminate	Atypical or Negative	Test Value X²; p
Positive	BSTI guidance statement	Classical or probable COVID-19	N %	497 97.4	10 2.0	3 0.6	872.18; < 0.001
		Indeterminate	N %	0	52 86.7	8 13.3
		COVID-19 exclusion	N %	0	1 10.0	9 90.0
Negative	BSTI guidance statement	Classical or probable COVID-19	N %	30 100.0	0	0	785.64; < 0.001
		Indeterminate	N %	0	29 64.4	16 35.6
		COVID-19 exclusion	N %	0	9 4.2	207 95.8

RT-PCR observer B				RSNA expert consensus statement			Test value X²; p
RT-PCR observer B				Typical	Indeterminate	Atypical or negative	Test value X²; p
Positive	BSTI guidance statement	Classical or probable COVID-19	N %	495 98.0	9 1.8	1 0.2	881.49; < 0.001
		Indeterminate	N %	1 1.8	44 78.6	11 19.6
		COVID-19 exclusion	N %	0	1 5.3	18 94.7
Negative	BSTI guidance statement	Classical or probable COVID-19	N %	28 96.5	1 3.5	0	893.98; < 0.001
		Indeterminate	N %	0	41 83.7	8 16.3
		COVID-19 exclusion	N %	0	4 1.9	209 98.1

ISSN: 1471-2342