Table 2. Summary of study findings.

Study	Total number of COVID-19 patients included	Positive early RT-PCR	Positive early CT	Comments
Ai 202014	1014	601	888	Average interval between tests: 1 day (less than or equal to 7 days). 308 patients had negative RT-PCR and positive CT. 21 patients had positive RT-PCR and negative CT. 580 patients with positive RT-PCR had positive CT. 258 multiple RT-PCR: average conversion time was 5 days. 10 out of 15 RT-PCR conversions had CT findings when the RT-PCR was negative.
Bernheim 202018	121	61 out of 69 tested in the early and intermediate group	46 out of 69 tested in the early and intermediate group	121 patients divided in three groups: Early group: 0-2 days of symptoms. Intermediate group: 3-5 days of symptoms. Late group: 6-12 days of symptoms.
Fang 202011	51	36	50	Average time between symptoms and CT or RT-PCR: 3 days
He 20209	34	27	26	Performed both tests in the first 2-5 days of symptoms. 48 initial RT-PCR were true negative. 7 initial RT-PCR were false negative. 46 CT were true negative. 8 CT were false positive. 2 CT were false negative.
Long 202017	36	30	35	Performed both tests during the initial presentation of the disease. 30 patients had positive RT-PCR and 35 had positive CT. 6 patients had negative RT-PCR and positive CT. 1 patient had negative CT and positive RT-PCR. 51 patients had negative RT-PCR and positive CT.