Table 1.

Comparison of Diagnostic Tests of COVID-19

Intended Use	Methods	Description	Operating Temperature	Analytical Sensitivity	Specificity	Assay time	Ref.
•Detecting viral RNA (N, E, Orf1ab) •COVID-19 molecular diagnostics, particularly at early stage	RT-qPCR	•Regular PCR •Gold standard	Thermal cycling	0.14 copy/μL	96%–100%	2–4 h	(Corman et al., 2020)
	ddPCR	•Droplet digital PCR •Highest sensitivity	Thermal cycling	0.02 copy/μL	94.9%	1 h	(Suo et al., 2020)
	RT-LAMP	•Isothermal •>4 pairs of primers	60°C–65°C	4.8 copy/μL	99%	15–60 min	(Zhang et al., 2020b)
	RT-RPA	•Isothermal •Using recombinase	37°C–42°C	0.2 copy/μL	NA	30 min	(Xia and Chen, 2020)
	RT-NEAR	•Isothermal •Using nicking endonuclease	55°C–59°C	0.13 copy/μL	100%	<15 min	(Abbott, 2020)
	DETECTR	•RT-LAMP (amplification) •CRISPR/Cas12 (detection)	62°C for RT-LAMP 37°C for LbCas12a	10 copy/μL	PPV: 95% NPV: 100%	30 min	(Broughton et al., 2020)
	STOP	•RT-LAMP (amplification) •CRISPR/Cas12 (detection)	60°C for RT-LAMP 60°C for AapCas12b	2 copy/μL	100%	70 min	(Joung et al., 2020)
•Detecting viral antigens •Potential for patient triaging	ELISA	•Immunoassay for virus •Lower sensitivity than PCR	Ambient	100 pg/mL	99.3%	3–5 h	(Freeman et al., 2020)
•Detecting antibodies developed by hosts •Applications in immunity check and serosurvey	RDT	•Immunoassay for IgG and IgM •Lateral flow device	Ambient	Qualitative	84.2%–100%	<15 min	(Liu et al., 2020c)
	ELISA	•Micro-well plate •Fluorescent or chromogenic	Ambient	100 pg/mL	67%–98.6%	3–5 h	(SinoBiological, 2020)
	Neutralization test	•Detecting active antibodies •Checking seroconversion	Ambient	0.22 copy/μL	100%	2–3 days	(Tan et al., 2020)

RT, reverse transcription; PCR, polymerase chain reaction; qPCR, quantitative PCR; ddPCR, digital droplet PCR; LAMP, loop-mediated isothermal amplification; RPA, recombinase polymerase amplification; NEAR, nicking endonuclease amplification reaction; DETECTR, DNA endonuclease-targeted CRISPR transreporter; STOP, SHERLOCK Testing in One Pot; NA, not available for clinical samples; PPV, positive predictive value; NPV, negative predictive value; ELISA, enzyme=linked immunoabsorbent assay; RDT, rapid diagnostic test.