. 2017 Apr 6;12(4):e0175247. doi: 10.1371/journal.pone.0175247

Table 1. Methods evaluated during the interlaboratory test performance study.

Methods			M1	M2	Ma	M3	M4	M5	M6
Type of amplification			End-point PCR	End-point PCR	End-point PCR	Real-time PCR	Real-time PCR	Real-time PCR	Real-time PCR
Type of amplification			Nested-PCR	Duplex nested-PCR	Nested-PCR followed by RFLP analysis	Simplex PCR	Simplex PCR	Triplex PCR	Triplex PCR
Targeted area of the genome			16S rDNA	SecY gene	16S rDNA	16S rDNA	SecY gene	map gene	unknown
Bibliographical references			[11, 14]	[18] [13, 15]	[11]	[15]	[16]	[17]	Under-patent (IPADLAB)
Evaluation of analytical specificity	Number of laboratories^a		14	12 (13)^c	5 (6)^c	7	10	7 (8)^c	9
	Number of results^a ^b	overall	336	288 (312)	120 (144)	168	240	168 (192)	216
		from positive samples	210	180 (195)	75 (90)	105	150	105 (120)	135
		from negative samples	126	108 (117)	45 (54)	63	90	63 (72)	81
	Number of indeterminate results^a	overall	16	11 (11)	3 (3)	4	8	5 (11)	14
		from positive samples	9	8 (8)	2 (2)	0	3	2 (4)	5
		from negative samples	7	3 (3)	1 (1)	4	5	3 (7)	9
	Rate of indeterminate results (%)^a	overall	4.76	3.82 (3.53)	2.50 (2.08)	2.38	3.33	2.98 (5.73)	6.48
		from positive samples	4.29	4.44 (4.10)	2.67 (2.22)	0.00	2.00	1.90 (3.33)	3.70
		from negative samples	5.56	2.78 (2.56)	2.22 (1.85)	6.35	5.56	4.76 (9.72)	10.23
Evaluation of analytical sensitivity, repeatability and reproducibility	Number of laboratories		5	5	2	5	5	5	5
	Number of results		375	375	150	375	375	375	375

^aThe number in brackets indicates the value without exclusion of data

^bThe number of results was calculated as follows: number of laboratories x number of results per method and laboratory (overall, from positive samples and from negative samples). The number of results per method and laboratory from positive samples was 15; the number of results per method and laboratory from negative samples was 9 and the number of overall results per method and laboratory was 24

^cExclusion of results of P6 for method M2, results of P5 for method Ma and results of P9 for method M5 (considered as outliers, for more details: see “outlier results” section)