4. AOACRIMicroMethods-2018Awards

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C rowley et al .: J ournal of AOAC I nternational V ol . 97, N o . 2, 2014  439

Table 3. Individual collaborator results for queso fresco a (25 g test portions) VIDAS LPT b High-level test portions Low-level test portions

Uninoculated test portions Lab 1 2 3 4 5 6 7 8 9 10 11 12 1 2 3 4 5 6 7 8 9 10 11 12 1 2 3 4 5 6 7 8 9 10 11 12 1 + + + + + + + + + + + + + + + – – – – + – + – + – – – – – – – – – – – – 2 + + + + + + + + + + + + + – + – – – – + – – – + – – – – – – – – – – – – 3 + + + + + + + + + + + + – – + + – + – – – + – – – – – – – – – – – – – – 4 + + + + + + + + + + + + + – + + + – + – – + + – – – – – – – – – – – – – 5 + + + + + + + + + + + + + – + – – + + – – – – + – – – – – – – – – – – – 6 + + + + + + + + + + + + + – – – – + – + + – + + – – – – – – – – – – – – 7 + + + + + + + + + + + + – – + + – – – + – + + + – – – – – – – – – – – – 8 + + + + + + + + + + + + + + – + – – + + + + – + – – – – – – – – – – – – 9 + + + + + + + + + + + + + + – + – + – – + – + + – – – – – – – – – – – – 10 + + + + + + + + + + + + – – – + + – – + – + + + – – – – – – – – – – – – 11 c + + + + + + + + + + + + – – – + + – – + – + + + – – – – – – – – – – – – 12 + + + + + + + + + + + + + – – – + – + + + + + – – – – – – – – – – – – – 13 + + + + + + + + + + + + – – – + + – + + + – + + – – – – – – – – – – – – 14 + + + + + + + + + + + + – + – + + – – – + + – d – d – – – – – – – – – – d – – AOAC 993.12 1 + + + + + + + + + + + + – + – + + + – – + – – – – – – – – – – – – – – – 2 + + + + + + + + + + + + + + + + – + – – – – – – – – – – – – – – – – – – 3 + + + + + + + + + + + + + – + + + – – + + – – – – – – – – – – – – – – – 4 + + + + + + + + + + + + + + – + + – – – + – + + – – – – – – – – – – – – 5 + + + + + + + + + + + + + + + – + – – – – – – – – – – – – – – – – – – – 6 + + + + + + + + + + + + – – – – – + + + + – + + – – – – – – – – – – – – 7 + + + + + + + + + + + + – – – – + + – + + + + + – – – – – – – – – – – – 8 + + + + + + + + + + + + – – – – – – + + + + + + – – – – – – – – – – – – 9 + + + + + + + + + + + + – – – – + + – + + + + + – – – – – – – – – – – – 10 + + + + + + + + + + + + – – + + – – + – + – + + – – – – – – – – – – – – 11 c + + + + + + + + + + + + – + e + + + + – – + – + + + e + e + e – – – + e + e – – + e + c 12 + + + + + + + + + + + + + + – + + – – – + – – + – – – – – – – – – – – – 13 + + + + + + + + + + + + – – + + + – – – – – + + – – – – – – – – – – – – 14 + + + + + + + + + + + + – – – – + – – + + + + + – – – – – – – – – – – – a + = Listeria spp. were detected in samples; – = Listeria spp. were not detected in sample. b Confirmed results from OXA and ALOA were identical for each test portion. c Results were not used in statistical analysis. d Sample was presumptive positive on VIDAS LPT but confirmed negative indicating a false-positive result. e Result reported as L. grayi (doubtful API Profile).

LPT. The confidence intervals obtained for dLPOD C indicated no significant difference between the two methods. dLPOD CP values of 0.00 (–0.03, 0.03) were obtained between presumptive and confirmed VIDAS LPT results. The confidence intervals obtained for dLPOD CP indicated no significant difference between the presumptive and confirmed results. Detailed results of the POD statistical analysis are presented in Table 2013.10B , as supplemental data on the J. AOAC Int. website, Tables 2C–D, and Figures  2 A–D.

portions confirmed positive. For the uninoculated controls, 0 out of 144 test portions confirmed positive. For the low-level inoculum, dLPOD C values of 0.01 (–0.10, 0.13) were obtained between AOAC 993.12 and VIDAS LPT. The confidence intervals obtained for dLPOD C indicated no significant difference between the two methods. dLPOD CP values of 0.00 (–0.12, 0.12) were obtained between presumptive and confirmed VIDAS LPT results. The confidence intervals obtained for dLPOD CP indicated no significant difference between the presumptive and confirmed results using either confirmation process. For the high-level inoculum, dLPOD C values of 0.00 (–0.03, 0.03) were obtained between AOAC 993.12 and VIDAS 03/10/2019

ALOA Chromogenic Agar

Confirmatory results obtained from the ALOA chromogenic