347 / 363
C
rowley
et al
.:
J
ournal of
AOAC I
nternational
V
ol
.
97, N
o
. 2, 2014
445
monocytogenes
(LMX) assay kit from bioMérieux (595 Anglum
Rd, Hazelwood, MO 63042-2330).
(
a
)
VIDAS or miniVIDAS automated immunoassay System.
(
b
)
LMX reagent strips.—
Sixty polypropylene strips of
10 wells, each strip covered with a foil seal and label. The
10 wells contain the reagents in Table
2013.11C
.
(
c
)
SPR.—
Sixty SPRs coated with proteins specific for
Listeria
receptors
.
(
d
)
Standard.—
One vial (1×6 mL). Ready-to-use. Contains
Table 2013.11A. Summary of results for the detection of
Listeria monocytogenes
in queso fresco (25 g)
Method
a
VIDAS LMX w/OXA
VIDAS LMX w/ALOA
Inoculation level
Uninoculated
Low
High Uninoculated
Low
High
Candidate presumptive positive/total
No. samples analyzed
0/156
77/156
156/156
0/156
77/156
156/156
Candidate presumptive POD (CP)
0.00
0.49
1.00
0.00
0.49
1.00
(0.00, 0.02)
(0.41, 0.58) (0.98, 1.00)
(0.00, 0.02)
(0.41, 0.58)
(0.98, 1.00)
s
r
b
0.00
0.51
0.00
0.00
0.51
0.00
(0.00, 0.15)
(0.46, 0.52) (0.00, 0.15)
(0.00, 0.15)
(0.46, 0.52)
(0.00, 0.15)
s
L
c
0.00
0.00
0.00
0.00
0.00
0.00
(0.00, 0.15)
(0.00, 0.12) (0.00, 0.15)
(0.00, 0.15)
(0.00, 0.12)
(0.00, 0.15)
s
R
d
0.00
0.51
0.00
0.00
0.51
0.00
(0.00, 0.21)
(0.47, 0.52) (0.00, 0.21)
(0.00, 0.21)
(0.47, 0.52)
(0.00, 0.21)
P
value
e
1.0000
0.9772
1.0000
1.0000
0.9772
1.0000
Candidate confirmed positive/total No. samples analyzed 0/156
75/156
156/156
0/156
75/156
156/156
Candidate confirmed POD (CC)
0.00
0.48
1.00
0.00
0.48
1.00
(0.00, 0.02)
(0.40, 0.56) (0.98, 1.00)
(0.00, 0.02)
(0.40, 0.56)
(0.98, 1.00)
s
r
0.00
0.51
0.00
0.00
0.51
0.00
(0.00, 0.15)
(0.46, 0.52) (0.00, 0.15)
(0.00, 0.15)
(0.46, 0.52)
(0.00, 0.15)
s
L
0.00
0.00
0.00
0.00
0.00
0.00
(0.00, 0.15)
(0.00, 0.14) (0.00, 0.15)
(0.00, 0.15)
(0.00, 0.14)
(0.00, 0.15)
s
R
0.00
0.51
0.00
0.00
0.51
0.00
(0.00, 0.21)
(0.46, 0.52) (0.00, 0.21)
(0.00, 0.21)
(0.46, 0.52)
(0.00, 0.21)
P
value
1.0000
0.8718
1.0000
1.0000
0.8718
1.0000
Positive reference samples/total No. samples analyzed
0/156
69/156
153/156
0/156
69/156
153/156
Reference POD
0.00
0.44
0.98
0.00
0.44
0.98
(0.00, 0.02)
(0.36, 0.52) (0.94, 0.99)
(0.00, 0.02)
(0.36, 0.52)
(0.94, 0.99)
s
r
0.00
0.51
0.13
0.00
0.51
0.13
(0.00, 0.15)
(0.46, 0.52) (0.12, 0.15)
(0.00, 0.15)
(0.46, 0.52)
(0.12, 0.15)
s
L
0.00
0.00
0.03
0.00
0.00
0.03
(0.00, 0.15)
(0.00, 0.13) (0.00, 0.07)
(0.00, 0.15)
(0.00, 0.13)
(0.00, 0.07)
s
R
0.00
0.51
0.14
0.00
0.51
0.14
(0.00, 0.21)
(0.46, 0.52) (0.12, 0.16)
(0.00, 0.21)
(0.46, 0.52)
(0.12, 0.16)
P
value
1.0000
0.9320
0.0877
1.0000
0.9320
0.0877
dLPOD (candidate vs reference)
0.00
0.04
0.02
0.00
0.04
0.02
(–0.02, 0.02) (–0.08, 0.15) (–0.01, 0.06)
(–0.02, 0.02)
(–0.08, 0.15) (–0.01, 0.06)
dLPOD (candidate presumptive vs candidate confirmed)
0.00
0.01
0.00
0.00
0.01
0.00
(–0.02, 0.02) (–0.10, 0.13) (–0.02, 0.02) (–0.02, 0.02)
(–0.10, 0.13) (–0.02, 0.02)
a
Results include 95% confidence intervals.
b
Repeatability standard deviation.
c
Among-laboratory standard deviation.
d
Reproducibility standard deviation.
e
P
value = Homogeneity test of laboratory PODs.
Candidates for 2016 Method of the Year
346