Study	Study design	Number	Gender (male/female)	Age (years), median (range) or mean±SD	Nationality	Participants	Collecting method	Correlation	TP	FN	FP	TN
Williams et al,¹⁰	case-control	89	NR	NR	Australia	symptomatic	Only oral cavity saliva		33	6	1	49
Landry et al,¹³	cohort	124	NR	NR	USA	symptomatic	Only oral cavity saliva	0.851	30	5	0	89
Griesemer et al,¹⁹	cohort	463	246/117	14-77	USA	mixed	Oral cavity saliva (not defined)		91	14	13	345
Bhattacharya et al,²⁵	case-control	74	NR	NR	India	symptomatic	Oral cavity saliva (not defined)		53	5	0	106
Byrne et al,²⁶	cohort	110	61/49	NR	England	symptomatic	Only oral cavity saliva		12	2	0	96
Caulley et al,²⁰		1939	NR	NR	Canada	mixed			34	22	14	1869
Hanson et al,¹⁴		354	188/166	35 (18-75)	USA	symptomatic		0.912	75	5	6	268
Moreno-Contreras et al,¹²		182	116/137	41±14.4	Mexico		Oral cavity saliva (not defined)		41	11	28	102
Pasomsub et al,⁷	cross-sectional	200	69/131	36 (28-48)	Thailand		Only oral cavity saliva	0.851	16	3	2	179
Skolimowska et al,¹¹	cohort	131	43/89	39 (30-51)	England				15	3	1	112
Vaz et al,¹⁶		155	46/103	40 (33-48.5)	Brazil			0.922	67	4	2	82
Yokota et al,⁸ (airport)		1763	927/832/4 (unknown)	33.5 (22.6-47.4)	Japan	asymptomatic	Oral cavity saliva (not defined)		4	1	0	1758
Yokota et al,⁸ (contact)		161	44/26/91 (unknown)	44.9 (29.8-66.4)	Japan	asymptomatic			38	3	6	114
Güçlü et al,¹⁷	cross-sectional	64	37/27	51.04±17.9	Turkey	symptomatic		0.744	23	4	4	33
Senok et al,²¹		401	329/72	35.5±9.5	UAE	asymptomatic	Only oral cavity saliva	0.68	19	7	9	366
Altawalah et al,¹⁸		891	NR	NR	Kuwait	symptomatic	Enhanced saliva	0.814	287	57	18	529
Procop et al,¹⁵		224	NR	NR	USA	symptomatic	Enhanced saliva		38	0	1	177
Kandel et al,²³	cohort	429	295/134	42 (30-54)	Canada	mixed	Only oral cavity saliva	0.91	39	4	3	383
Braz-Silva et al,²⁴		201	75/126	40 (31-52)	Brazil	symptomatic	Only oral cavity saliva		55	15	0	131
Babady et al,²²		87	NR	NR	USA		Enhanced saliva		16	1	1	69
Dogan et al,²⁷	cross-sectional	98	NR	NR	Turkey		Only oral cavity saliva		30	25	5	38
Wong et al,²⁸	retrospective	229	NR	NR	China	mixed			104	18	37	70
Iwasaki et al,²⁹	cross-sectional	66	NR	NR	Japan	symptomatic		0.874	8	1	1	66
Kojima et al,³⁰	prospective cross-sectional	45	NR	45 (21-53)	USA		Enhanced saliva		20	3	6	16
McCormick-Baw et al,³¹	prospective cross-sectional	155	NR	NR	USA		Only oral cavity saliva (not defined)		47	2	1	105
Miller et al,³²	cross-sectional	91	NR	NR	USA	mixed	Only oral cavity saliva		33	1	1	56
Vogels et al,³³	prospective cross-sectional	67	NR	NR	USA		Only oral cavity saliva (not defined)		32	2	3	30
Boerger et al,³⁴	prospective cross-sectional	281	NR	NR	USA		Only oral cavity saliva		30	3	2	246
Toppings et al,³⁵	cross-sectional	63	NR	NR	Canada				28	2	0	33
Xun et al,³⁶	cross-sectional	104	NR	NR	USA				28	2	1	73
Masse et al,³⁷	prospective cross-sectional	143	63/80	35 (22.5-49)	France	symptomatic	Enhanced saliva	0.89	51	5	2	85
Sasikala et al,³⁸		200	140/60	37.9±12.8	India	mixed	Enhanced saliva		128	46	0	26
Mohd Thabit et al,³⁹		96	66/30	34±26 (12-95)	Malaysia		Only oral cavity saliva	0.69	45	11	4	36
Fernandes et al,⁴⁰	cohort	226	91/135	NR	Portugal				67	13	4	142
Marx et al,⁴¹	cross-sectional	730	420/310	NR	USA	symptomatic/mixed/asymptomatic		0.92	46	8	6	436
Abasiyanik et al,⁴²	cohort	92	NR	45 (30.58)	USA	symptomatic			16	0	7	69
Alkhateeb et al,⁴³	prospective cross-sectional	48	26/22	39.9±15.5	USA	symptomatic/mixed/asymptomatic	Enhanced saliva		12	3	0	18
Bidkar et al,⁴⁴	cross-sectional	80	49/31	36.4	India	mixed	Only oral cavity saliva		13	28	2	33
Stokes et al,⁴⁵	prospective cross-sectional	145	75/70	39.4	Canada	symptomatic			121	17	2	5
Fernández-González et al,⁴⁶	prospective cross-sectional	229	91/128	39 (21-48)	Spain	mixed		0.85	39	7	4	171
Herrera et al,⁴⁸	cross-sectional study	2107	NR	NR	Mexico	asymptomatic		0.852	139	34	10	1867
Trobajo-Sanmartín et al,⁴⁷	prospective cross-sectional	674	374/300	NR	Spain	mixed			168	156	3	309

SD: standard deviation, TP: true positive, FN: false negative, FP: false positive, TN: true negative NR: not reported