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Table 1. Multilaboratory collaborative study data for vitamin B
12
a
Lab
No. NIST 1849a
Adult milk
powder
Infant partially
hydrolyzed milk powder
Infant partially
hydrolyzed soy powder
Adult low-fat
powder
Child powder
Infant elemental
powdered
Infant milk
powder
Infant soy
powder
Infant milk RTF
Adult high-fat
RTF
Adult high-
protein RTF
1 42.1 45.4 0.306 0.308 0.360
0.359
0.212
0.222 0.687 0.680 0.934 0.963 0.532 0.516 0.227 0.230 0.415 0.431 0.290 0.295 1.53 1.19
b
0.19 0.17
2 43.7 47.1 0.313 0.341 0.423
0.436
0.283
0.280 0.698 0.665 0.932 0.938 0.562 0.577 0.248 0.230 0.444 0.466 0.269 0.300 1.58 1.70 1.33 1.31
3 39.5 43.1 0.300 0.293 0.305
0.292
0.228
0.276 0.638 0.625 0.987 0.978 0.487 0.465 0.226 0.245 0.429 0.363 0.304 0.266 1.37 1.37 0.953 0.830
4 44.0 40.7 0.283 0.310 0.273
0.306
0.246
0.268 0.660 0.606 1.01 0.972 0.532 0.537 0.201 0.226 0.420 0.413 0.305 0.311 0.804
c
0.683
c
0.989 0.944
5 42.9 38.0 0.250 0.238 0.331
0.402
0.183
0.261 0.590 0.510 0.885
c
0.767
c
0.520
d
0.670
d
0.183 0.187 0.416 0.375 0.155 0.242 1.27 1.25 0.941 0.793
6 35.2
c
19.9
c
NA
e
NA 0.305
0.312
0.173
0.155 0.627 0.570 NA NA 0.466 0.491 NA NA 0.271
c
0.345
c
NA NA NA NA NA NA
7 44.8 54.9 0.304 0.250 0.395
0.355
0.236
0.234 0.671 0.609 0.950 0.899 0.584 0.633 0.248 0.243 0.436 0.420 0.225 0.252 1.33 0.872
b
0.973 0.992
8 47.8 47.6 0.379 0.376 0.431
0.430
0.344
0.305 0.661 0.650 0.957 0.991 0.635 0.657 0.230 0.218 0.475 0.441 0.300 0.286 1.63 1.34 1.36 1.32
9 40.5 39.9 0.257 0.271 0.300
0.319
0.241
0.242 0.584 0.549 1.03 0.959 0.501 0.477 0.250 0.236 0.409 0.402 0.229 0.241 1.44 0.929
b
1.13 0.893
10 42.6 40.2 0.363 0.279 0.471
0.487
0.317
0.284 0.686 0.757 0.965 1.01 0.564 0.556 0.330
f
0.270
f
0.469 0.477 0.296 0.327 1.79 1.57 1.33 1.26
11 43.3 45.0 0.267 0.319 0.463
0.456
NA
NA NA NA NA NA NA NA 0.244 0.221 0.438 0.421 NA NA 1.59 0.932
b
0.938 1.01
a
Concentration in g/100 µg RTF liquid for all products except NIST 1849a; NIST 1849a concentration in µg/kg powder.
b
Data excluded. Sample was mislabeled. Sample is really adult high-protein RTF liquid.
c
Data excluded. Failed single Grubbs’ test.
d
Data excluded. Failed Cochran’s test.
e
NA = Not applicable. Laboratory did not receive sample.
f
Data excluded. Failed double Grubbs’ test.
Table 2. Multilaboratory collaborative study results for vitamin B
12
Sample type
Total No. labs
a
Total No. replicates
b
Mean, µg/100 g RTF
SD
r
SD
R
RSD
r
, % RSD
R
, %
HorRat
Infant formula (NIST SRM 1849a)
11 (1)
22 (2)
43.70
c
3.010
3.86
6.90
8.84
0.34
Infant formula powder soy-based
11 (1)
22 (2)
0.428
0.021
0.0305
4.85
7.13
0.20
Infant formula powder milk-based
10 (1)
20 (2)
0.227
0.011
0.0202
4.90
8.90
0.22
Infant formula RTF milk-based
9 (0)
18 (0)
0.272
0.026
0.0427
9.46
15.70
0.40
Infant formula powder partial hydrolyzed milk-based
11 (0)
22 (0)
0.373
0.020
0.0694
5.35
18.60
0.50
Infant formula powder partial hydrolyzed soy-based
10 (0)
20 (0)
0.250
0.024
0.0487
9.77
19.50
0.50
Adult nutritional powder milk-based
10 (0)
20 (0)
0.300
0.027
0.0416
8.99
13.80
0.36
Adult nutritional RTF high protein
10 (0)
20 (0)
1.080
0.073
0.1900
6.74
17.50
0.55
Child formula powder
9 (1)
18 (2)
0.967
0.029
0.0342
2.98
3.54
0.11
Adult nutritional RTF high fat
10 (1)
16 (2)
1.480
0.122
0.1710
8.23
11.50
0.38
Infant elemental powder
10 (1)
20 (2)
0.543
0.017
0.0603
3.11
11.10
0.32
Adult nutritional powder low fat
10 (0)
20 (0)
0.636
0.035
0.0587
5.47
9.23
0.27
a
Number of laboratories submitting data (number of laboratories with data removed as outliers).
b
Number of samples with results submitted (number of samples removed as outliers).
c
Data reported as µg/kg powder.
14