Table 7. Statistical summary for the POD model applied to the different methods evaluated during the test performance study.

Performance criteria or parameters	Dilution levelsb	Results obtained for each method
		M1	M2	Maa	M3	M4	M5	M6
LPOD c (95%CI)	D1	0.89	0.43	0.77	0.77	0.83	1.00	1.00
		(0.80; 0.94)	(0.00; 0.93)	(0.00; 1.00)	(0.59; 0.96)	(0.56; 1.00)	(0.95; 1.00)	(0.95; 1.00)
	D2	0.91	0.39	0.87	0.88	0.99	1.00	0.96
		(0.82; 0.95)	(0.00; 1.00)	(0.70; 0.95)	(0.79; 0.94)	(0.92; 1.00)	(0.95; 1.00)	(0.87; 0.99)
	D3	0.75	0.33	0.80	0.93	0.96	0.97	0.91
		(0.67; 0.82)	(0.00; 0.89)	(0.80; 0.80)	(0.85; 0.97)	(0.88; 0.99)	(0.91; 0.99)	(0.82; 0.95)
	D4	0.51	0.27	0.70	0.87	0.83	0.92	0.84
		(0.37; 0.65)	(0.00; 0.70)	(0.63; 0.77)	(0.77; 0.93)	(0.69; 0.96)	(0.84; 0.96)	(0.81; 0.87)
	D5	0.64	0.20	0.73	0.67	0.73	0.87	0.71
		(0.44; 0.84)	(0.00; 0.41)	(0.24; 1.00)	(0.47; 0.86)	(0.61; 0.85)	(0.77; 0.93)	(0.61; 0.81)
dLPOD d (95%CI) vs. M5e	D1	-0.11	-0.57	-0.23	-0.23	-0.17	-	0.00
		(-0.20; -0.04)	(-1 .00; -0.07)	(-1.00; 0.00)	(-0.41; -0.04)	(-0.44; 0.00)		(-0.05; 0.05)
	D2	-0.09	-0.61	-0.13	-0.12	-0.01	-	-0.04
		(-0.18;-0.03)	(-1.00; -0.00)	(-0.30;-0.04)	(-0.21; -0.05)	(-0.07; 0.04)		(-0.11; 0.02)
	D3	-0.23	-0.64	-0.17	-0.04	-0.01	-	-0.07
		(-0.31;-0.12)	(-0.97;-0.08)	(-0.19;-0.11)	(-0.12; 0.04)	(-0.09; 0.06)		(-0.16; 0.01)
	D4	-0.41	-0.65	-0.22	-0.05	-0.09	-	-0.08
		(-0.56;-0.25)	(-0.92;-0.21)	(-0.30;-0.11)	(-0.16; 0.05)	(-0.23; 0.06)		(-0.13; 0.00)
	D5	-0.23	-0.67	-0.13	-0.20	-0.13	-	-0.16
		(-0.43;-0.01)	(-0.87;-0.44)	(-0.63;0.15)	(-0.40; 0.02)	(-0.27; 0.02)		(-0.28;-0.02)
Repeatability standard deviation (sr)	D1	0.276	0.335	0.365	0.400	0.324	0.000	0.000
	D2	0.269	0.115	0.345	0.258	0.115	0.000	0.185
	D3	0.443	0.243	0.414	0.218	0.200	0.157	0.293
	D4	0.498	0.309	0.473	0.315	0.370	0.276	0.378
	D5	0.462	0.373	0.436	0.454	0.460	0.340	0.460
Laboratory standard deviation (sL)	D1	0.159	0.409	0.316	0.148	0.223	0.000	0.000
	D2	0.128	0.529	0.031	0.223	0.000	0.000	0.076
	D3	0.000	0.453	0.000	0.138	0.000	0.044	0.008
	D4	0.084	0.356	0.000	0.149	0.100	0.000	0.000
	D5	0.158	0.169	0.151	0.155	0.000	0.034	0.000
Reproducibility standard deviation (sR)	D1	0.318	0.529	0.483	0.426	0.393	0.000	0.000
	D2	0.298	0.542	0.346	0.341	0.115	0.000	0.200
	D3	0.443	0.514	0.414	0.258	0.2	0.163	0.293
	D4	0.505	0.471	0.473	0.348	0.384	0.276	0.378
	D5	0.488	0.409	0.462	0.479	0.460	0.343	0.460
p-value of Fisher-Snedecor test (ANOVA)f	D1	3.52e-4 S***	2.82e-12 S***	1.58e-3 S**	0.023 S*	1.881e-05 S***	-	-
	D2	3.04e-3 S***	< 2.2e-16 S***	0.299 NS	1.40e-07 S***	0.414 NS	-	0.012 S*
	D3	0.680 NS	< 2.2e-16 S***	1.000 NS	8.451e-05 S***	0.736 NS	0.083 NS	0.408 NS
	D4	0.234 NS	2.08e-11 S***	0.703 NS	3.25e-3 S***	0.091 NS	0.655 NS	0.967 NS
	D5	0.035 S*	5.00 e-3 S***	0.105 NS	0.035 S*	0.252 NS	0.342 NS	0.479 NS

^aValues for method Ma were calculated from the results of 2 laboratories (vs 5 for other methods)

^bD1: dilution 1.0·10⁻¹ (= samples A1-B1-C1); D2: dilution 1.0·10⁻² (= samples A2-B2-C2), D3: dilution 3.3·10⁻³ (= samples A3-B3-C3); D4: dilution 1.1·10⁻³ (= samples A4-B4-C4); D5: dilution 3.7·10⁻⁴ (= samples A5-B5-C5)

^cLaboratory probability of detection values: probability of detection values obtained during an interlaboratory comparison

^dDifference in laboratory probability of detection values

^eDifferences in LPOD values between each method and method M5 (considered in the calculation as the reference method). The shaded cells indicate a statistical significance between the compared method and M5 based on the fact that the confidence interval for dLPOD does not include zero

^fThe shaded cells indicate statistical significance for POD between laboratories. NS: not significant (p ≥ 0.05); S*: 0.01≤ p < 0.05; S**: 0.001 ≤ p < 0.01; S***: p < 0.001