NISTIR 7880-22 

NIST Micronutrients Measurement 

Quality Assurance Program 

Summer 2001 

Comparability Studies 

Results for Round Robin L 

Fat-Soluble Vitamins and Carotenoids in Human Serum 

and Round Robin 15 Ascorbic Acid in Human Serum 

David L. Duewer 

Sam A. Margolis (Retired) 

Katherine E. Sharpless 

Jeanice B. Thomas 

 

 

 

 

NISTIR 7880-22
 

NIST Micronutrients Measurement 

Quality Assurance Program 

Summer 2001 

Comparability Studies 

Results for Round Robin L 

Fat-Soluble Vitamins and Carotenoids in Human Serum 

and Round Robin 15 Ascorbic Acid in Human Serum 

David L. Duewer 

Sam A. Margolis (Retired) 

Katherine E. Sharpless 

Jeanice B. Thomas 

Chemical Sciences Division 

Materials Measurement Laboratory 

-XQH 2013 

U.S. Department of Commerce 

&DPHURQ).HUU\, Acting Secretary 

National Institute of Standards and Technology 

Patrick D. Gallagher, Under Secretary of Commerce for Standards and Technology and Director 
(This page intentionally blank) 

ii
 
 

 

 

Abstract 

The National Institute of Standards and Technology coordinates the Micronutrients Measurement 

Quality Assurance Program (MMQAP) for laboratories that measure fat- and water-soluble vitamins 

and carotenoids in human serum and plasma. This report describes the design of and results for the 

Summer 2001 MMQAP measurement comparability improvement studies: 1) Round Robin L FatSoluble Vitamins and Carotenoids in Human Serum and 2) Round Robin 15 Total Ascorbic Acid in 

Human Serum. The materials for both studies were shipped to participants in June 2001; 

participants were requested to provide their measurement results by mid-September, 2001. 

Keywords 

Human Serum
 

Retinol, α-Tocopherol, γ-Tocopherol, Total and Trans-β-Carotene
 

Total Ascorbic Acid
 

iii 
 

 

 

 

 

 

 

Table of Contents 

Abstract............................................................................................................................................... iii
 

Keywords ............................................................................................................................................ iii
 

Table of Contents ............................................................................................................................... iv
 

Introduction......................................................................................................................................... 1
 

Round Robin L: Fat-Soluble Vitamins and Carotenoids in Human Serum ................................ 1
 

Round Robin 15: Vitamin C in Human Serum............................................................................... 2
 

References ............................................................................................................................................ 3
 

Appendix A. Shipping Package Inserts for RR15........................................................................ A1
 

Appendix B. Final Report for RR15 ..............................................................................................B1
 

Appendix C. “All-Lab Report” for RR15 ......................................................................................C1
 

Appendix D. Representative “Individualized Report” for RR15 ............................................... D1
 

Appendix E. Shipping Package Inserts for RR15 ......................................................................... E1
 

Appendix F. Final Report for RR15............................................................................................... F1
 

Appendix G. “All-Lab Report” for RR15..................................................................................... G1
 

Appendix H. Representative “Individualized Report” for RR15............................................... H1
 

iv 
 

Introduction 

Beginning in 1988, the National Institute of Standards and Technology (NIST) has coordinated the 

Micronutrients Measurement Quality Assurance Program (MMQAP) for laboratories that measure 

fat- and water-soluble vitamins and carotenoids in human serum and plasma. The MMQAP 

provides participants with measurement comparability assessment through use of interlaboratory 

studies, Standard Reference Materials (SRMs) and control materials, and methods development and 

validation. Serum-based samples with assigned values for the target analytes (retinol, alphatocopherol, gamma/beta-tocopherol, trans- and total beta-carotene, and total ascorbic acid) and 

performance-evaluation standards are distributed by NIST to laboratories for analysis. 

Participants use the methodology of their choice to determine analyte content in the control and 

study materials. Participants provide their data to NIST, where it is compiled and evaluated for 

trueness relative to the NIST value, within-laboratory precision, and concordance within the 

participant community. NIST provides the participants with a technical summary report concerning 

their performance for each exercise and suggestions for methods development and refinement. 

Participants who have concerns regarding their laboratory’s performance are encouraged to consult 

with the MMQAP coordinators. 

All MMQAP interlaboratory studies consist of individual units of batch-prepared samples that are 

distributed to each participant. For historical reasons these studies are referred to as “Round 

Robins”. The MMQAP program and the nature of its studies are described elsewhere. [1,2] 

Round Robin L: Fat-Soluble Vitamins and Carotenoids in Human Serum 

Participants in the MMQAP Fat-Soluble Vitamins and Carotenoids in Human Serum Round Robin L 

comparability study (hereafter referred to as RR15) received three lyophilized and two liquid-frozen 

human serum test samples for analysis. Unless multiple vials were previously requested, 

participants received one vial of each serum. These sera were shipped on dry ice to participants in 

June 2001. The communication materials included in the sample shipment are provided in 

Appendix A. 

Participants are requested to report values for all fat-soluble vitamin-related analytes that are of 

interest to their organizations. Not all participants report values for the target analytes, and many 

participants report values for non-target analytes. 

The final report delivered to every participant in RR15 consists of three documents: 

•	 A cover letter for the current study, a brief description of the other two documents, and a 

discussion of our analysis of the overall results that may be of broad interest. This cover 

letter is reproduced as Appendix B. 

•	 The “All-Lab Report” that lists all of the reported measurement results, a number of 

consensus statistics for analytes reported by more than one participant, and the mean median 

and pooled SD from any prior distributions of the serum. This report also provides a 

numerical “score card” for each participant’s measurement comparability for the more 

commonly reported analytes. This report is reproduced as Appendix C. 

1
 
 

 

•	 An “Individualized Report” that graphically analyzes each participant’s results for all 

analytes reported by at least five participants. This report also provides a graphical summary 

of their measurement comparability. The graphical tools used in this report are described in 

detail elsewhere [3]. An example “Individualized Report” is reproduced as Appendix D. 

Round Robin 15: Vitamin C in Human Serum 

Participants in the MMQAP Vitamin C in Human Serum Round Robin 15 comparability study 

(hereafter referred to as RR15) received three frozen serum test samples and a solid ascorbic acid 

control material for analysis. Unless multiple vials were previously requested, participants received 

one vial of each material. These sample materials were shipped on dry ice to participants in June 

2001. The communication materials included in the sample shipment are provided in Appendix E. 

The test serum materials were prepared by adding equal volumes of 10 % metaphosphoric acid 

(MPA) to human serum that had been spiked with ascorbic acid. While these samples contain some 

dehydroascorbic acid, its content is variable. Therefore, the participants report only total ascorbic 

acid (TAA, ascorbic acid plus dehydroascorbic acid). Participants are also encouraged to prepare 

calibration solutions from the supplied solid control to enable calibrating their serum measurements 

to the same reference standard. 

The final report delivered to every participant in RR15 consists of three documents: 

•	 A cover letter for the current study, a brief description of the other two documents, and a 

discussion of our analysis of overall results that may be of broad interest. This cover letter is 

reproduced as Appendix F. 

•	 The “All-Lab Report” that summarizes all of the reported measurement results and provides 

several consensus statistics. This report is reproduced as Appendix G. 

•	 An “Individualized Report” that graphically analyzes each participant’s results for TAA, 

including a graphical summary of their measurement comparability. The graphical tools 

used in this report are described in detail elsewhere [3]. An example “Individualized Report” 

is reproduced as Appendix H. 

2
 
 

 

References 

1 Duewer DL, Brown Thomas J, Kline MC, MacCrehan WA, Schaffer R, Sharpless KE, May WE, 

Crowell JA. NIST/NCI Micronutrients Measurement Quality Assurance Program: Measurement 

Repeatabilities and Reproducibilities for Fat-Soluble Vitamin-Related Compounds in Human 

Sera. Anal Chem 1997;69(7):1406-1413. 

2 Margolis SA, Duewer DL. Measurement Of Ascorbic Acid in Human Plasma and Serum: 

Stability, Intralaboratory Repeatability, and Interlaboratory Reproducibility. Clin Chem 

1996;42(8):1257-1262. 

3 Duewer DL, Kline MC, Sharpless KE, Brown Thomas J, Gary KT, Sowell AL. Micronutrients 

Measurement Quality Assurance Program: Helping Participants Use Interlaboratory Comparison 

Exercise Results to Improve Their Long-Term Measurement Performance. Anal Chem 

1999;71(9):1870-1878. 

3
 
Appendix A. Shipping Package Inserts for RR15 

The following three items were included in each package shipped to an RR15 participant: 

• Cover letter 

• Datasheet 

• Packing List and Shipment Receipt Confirmation Form 

The cover letter and datasheet were enclosed in a sealed waterproof bag along with the 

samples themselves. The packing list was placed at the top of the shipping box, between 

the cardboard covering and the foam insulation. 

A1
June 8, 2001 

Dear Colleague: 

UNITED STATES DEPARTMENT OF COMMERCE 

National Institute of Standards and Technology 

Gaithersburg, Maryland 20899-0001 

Enclosed is the set of samples for the second quality assurance round robin exercise (Round Robin L) for 

2001. You will find one vial of each of three lyophilized and two liquid-frozen serum samples for 

analysis along with a form for reporting your results. When reporting your results, please submit one 

value for each analyte for a given serum sample. If an obtained value is below your limit of quantitation, 

please indicate this result on the form by using NQ (Not Quantitated). For" analytes not measured, please 

leave a blank. Results are due to NIST by September 14, 2001. Results received two weeks after the 

due date will not be included in the summary report for this round robin study. The feedback report 

concerning the study will be provided around mid-October. 

Lyophilized samples should be reconstituted with 1.0 mL of HPLC-grade water or equivalent. We 

recommend that dissolution be facilitated with 3 to 5 min agitation in an ultrasonic bath or at least 30 

min at room temperature with intermittent swirling. (CAUTION: Vigorous shaking will cause foaming 

and possibly interfere with accurate measurement.· The rubber stopper contains phthalate esters that will 

leach into the sample upon intermittent contact of the liquid sample with the stopper. These esters 

absorb strongly in the UV region and elute near retinal in most LC systems creating analytical 

problems.) Pipette a known volume of serum from the vial for analysis. (The final volume of the 

reconstituted sample is greater than 1.0 mL). Liquid-frozen samples 274 and 275 should not be 

reconstituted. 

For consistency, we request that laboratories use the following absorptivities (E 1 % cm) in ethanol: 

retinal, 18~3 at 325 nm; retinyl palmitate, 975 at 325 nm; a-tocopherol, 75.8 at 292 nm; y-tocopherol, 

91.4 at 298 nm; a-carotene, 2800 at 444 nm (in hexane); P-carotene, 2560 at 450 nm (in ethanol), 2592 

at 452 nm (in hexane); lycopene, 3450 at 472 nm (in hexane). 

Please mail or fax your results for Round Robin L to: 

Micronutrients Measurement Quality Assurance Program 

NIST 

100 Bureau Drive Stop 8392 

Gaithersburg, MD 20899-8392 

Fax: (301) 977-0685 

If you have questions regarding this round robin exercise, please call me at (301) 975-3120;e-mail me at 

jbthomas@nist.gov; or mail/fax queries to the above address. 

e~13~ lmtn 

ce Brown Thoma'.s 

arch Chemist 

Analytical Chemistry Division 

Chemical Science and Technology Laboratory 

Enclosures 

NISI 

A2
 

 

 

Participant #: ________ Date: _____________ 

Round Robin L 

NIST Micronutrients Measurement Quality Assurance Program 

Analyte 274 275 276 277 278 Units* 

total retinol 

trans-retinol 

retinyl palmitate 

α-tocopherol 

γ/β-tocopherol 

δ-tocopherol 

total β-carotene 

trans-β-carotene 

total cis-β-carotene 

total α-carotene 

trans-α-carotene 

total lycopene 

trans-lycopene 

total β-cryptoxanthin 

total α-cryptoxanthin 

total lutein 

total zeaxanthin 

total lutein&zeaxanthin 

ubiquinone-10 (Q10) 

phylloquinone (K1) 

25-hydroxyvitamin D 

Other analytes? 

* we prefer μg/mL 

Was sera 274 & 275 frozen when received? Yes | No 

Comments: 

Mail: M2QAP 

NIST, Stop 8392 Please return results on-or-before Fax: 301-977-0685 

Gaithersburg, MD 20899-8392 14-Sep-2001 Email: David.Duewer@NIST.gov 

A3
 

 

 

 

Participant #: ________ Date: _____________ 

Round Robin L
 

NIST Micronutrients Measurement Quality Assurance Program
 

Packing List and Shipment Receipt Confirmation Form
 

The enclosed bubble-pack (should) contain one vial each of the following five sera: 

Serum Form Reconstitute? 

#274 Liquid frozen No 

#275 

#276 

#277 

#278 

Liquid frozen 

Lyophilized 

Lyophilized 

Lyophilized 

No 

Yes (1 ml H2O) 

Yes (1 ml H2O) 

Yes (1 ml H2O) 

Please 1) Open the pack immediately 

2) Check that it contains one vial each of the above samples 

3) Check if sera #274 and #275 arrived frozen 

4) Store the samples upright at -20  ̊C or below until analysis 

5) Complete the following information 

6) Fax the completed form to us at 301-977-0685 

(or email requested information to david.duewer@nist.gov) 

1) Date this shipment arrived: ___________________________ 

2) Are all five vials intact? Yes | No 

If "No", which one(s) were damaged? 

3) Was there any dry-ice left in cooler? Yes | No 

4) Did sera #274 and #275 arrive frozen? Yes | No 

5) At what temperature are you storing the samples? _______  ̊C 

6) When do you anticipate analyzing these samples? ________________________ 

Your prompt return of this information will help control M2QAP expenses. 

The M2QAP Gang 

Mail: M2QAP 

NIST, Stop 8392 Fax: 301-977-0685 

Gaithersburg, MD 20899-8392 Email: David.Duewer@NIST.gov 

A4
 

 

Appendix B. Final Report for RR15 

The following three pages are the final report as provided to all participants: 

•	 Cover letter. 

•	 An information sheet that: 

o	 describes the contents of the “All-Lab” report, 

o	 describes the content of the “Individualized” report, 

o	 describes the nature of the test samples and details their previous distributions, 

if any, and 

o	 summarizes aspects of the study that we believe may be of interest to the 

participants. 

B1
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NIST CENTENNIALC 

October 31, 2001 

Dear Colleague: 

UNITED STATES DEPARTMENT OF COMMERCE 

National Institute of Standards and Technology 

Gaithersburg, Maryland 20899-

Enclosed is the summary report of the results for Round Robin L (RR 50) for fat-soluble 

vitamins and carotenoids. Included in this report are: a summary of data for all 

laboratories; the measurement comparability summary for evaluating laboratory 

performance; lyophilized vs. fresh-frozen commutability data, a summary of individual 

laboratory performance and interlaboratory accuracy and precision; and a summary of the 

NIST assigned value (NA V) vs. your laboratory value for the analytes that you measured. 

As in previous reports, the NIST-assigned values are equally weighted means of the 

medians from this interlaboratory comparison exercise and the means from the analyses 

performed by NIST. 

Data for evaluating laboratory performance in RR 50 are provided in the comparability 

summary (Score Card) on page 6 of the "All Lab Report." Laboratory comparability is 

summarized as follows: results rated 1 to 3 are within 1 to 3 standard deviation(s) of the 

assigned value, respectively; those rated 4 are >3 standard deviations from the assigned 

value. 

If you have concerns regarding your laboratory's performance, we suggest that you obtain 

and analyze a unit of SRM 968c, Fat-Soluble Vitamins, Carotenoids, and Cholesterol in 

Human Serum. If your measured values do not agree with the certified values, we 

suggest that you contact us for consultation. 

Intent-to-participate forms for the 2002 QA program were mailed about two weeks ago. 

This form will provide us with formal notification of your intent to participate in the 

program for the upcoming year. The program will consist of two round robin studies for 

the fat-soluble vitamins and carotenoids and one study for vitamin C in serum. To 

participate in the fat-soluble vitamins and carotenoids in serum studies, the participation 

fee is $1600 for U.S. laboratories and $2000 for non-U.S. laboratories. To participate in 

the vitamin C in serum study, the participation fee is $800 for U.S. laboratories and 

$1000 for non-U.S. laboratories. We ask that you return the form to us by no later than 

November 30, 2001. 

B2
The following publication has been released. Please contact the corresponding author for 

reprints. 

"Stability of Ascorbic Acid in Solutions Stored in Autosampler Vials," Margolis, S. A. 

and Park, E., Clin. Chem., 47, 1463-4, 2001. 

If you have any questions regarding this report, please contact David Duewer at 301/975-

3935; e-mail: david.duewer@nist.gov, or me at 301/975-3120; e-mail: 

jbthomas@nist.gov; fax: 301/977-0685. 

· ce Brown Thomas 

Research Chemist 

Analytical Chemistry Division 

Chemical Science and Technology Laboratory 

cc: L. C. Sander 

S. A. Wise 

Enclosures 

B3
 

The NIST M2QAP Round Robin XLIX (RR50) report consists of: 

Page 

1 Your values, the number of labs reporting values, and our assigned values. 

2 to “Four Plot” summaries of your current and past measurement performance, one page for 

n each analyte you report that is also reported by at least 10 other participants. 

n+1 The “target” plot version of your “Comparability Summary” scores. 

Page “All Lab” Report 

1-4 

5a 

5b 

6 

Samples. 

Serum 

274 

275 

276 

277 

278 

“Individualized” Report 

A listing of all results and statistics for analytes reported by at least two laboratories.
 

A list of results for the four analytes reported by only one laboratory. 

A legend for the above two lists.
 

The “Comparability Summary” (or “Score Card”).
 

The five sera below were distributed in RR50. 

Description 

liquid-frozen material prepared from a native 

serum; partner to lyophilized serum 276 

liquid-frozen material prepared from a native 

serum; partner to lyophilized serum 277 

lyophilized material prepared from a native 

serum; partner to liquid-frozen serum 274 

lyophilized material prepared from a native 

serum; partner to liquid-frozen serum 275 

lyophilized material prepared from a native 

serum 

Prior Distribution 

as serum 267 in RR48 

as serum 271 in RR49 

as serum 270 in RR49 

as serum 266 in RR48 

as serum 192 in RR30 (3/94); serum 199 in 

RR32 (9/94); serum 218 in RR36 (3/96); 

and serum 250 in RR44 (9/98) 

Qualitative Observations 

Several participants noted the presence an “insoluble stringy clot” in Serum 275 and/or 277. We had 

similar reports from the earlier distributions of these sera. However, since the solids do not appear to 

affect measurements, we chose to redistribute this {liquid-frozen, lyophilized} pair to help complete our 

commutability study. 

All participants received their samples still frozen. We thank all of you who promptly confirmed receipt 

of the samples. Such prompt confirmation greatly simplifies our package delivery tracking and thus 

helps contain M2

QAP costs. We will be requesting similar confirmation in all future studies. 

Quantitative Results 

There has been no significant change in the median level or in the variability of any measurand in serum 

278 over eight years storage at –80 °C. 

While the liquid frozen and lyophilized sera of the commutability pairs were prepared from the same 

serum pool, the measurand concentrations in the lyophilized sera are expected and generally observed to 

be about 0.96x that of their liquid-frozen analogues. This is a simple dilution effect, since the lyophilized 

sera are reconstituted with 1 mL of water rather than to their original 1 mL total volume. 

B4
 

 

Appendix C. “All-Lab Report” for RR15 

The following six pages are the “All-Lab Report” as provided to all participants, with two 

exceptions: 

• the participant identifiers (Lab) have been altered. 

• the order in which the participant results are listed has been altered. 

The data summary in the “All-Lab Report” has been altered to ensure confidentiality of 

identification codes assigned to laboratories. The only attributed results are those 

reported by NIST. The NIST results are not used in the assessment of the consensus 

summary results of the study. 

C1
Round Robin L Laboratory Results
 

All Results in μg/mL
 

Total Retinol trans-Retinol Retinyl Palmitate α-Tocopherol γ/β-Tocopherol δ-To

C2

Lab 274 275 276 277 278 274 275 276 277 278 274 275 276 277 278 274 275 276 277 278 274 275 276 277 278 274 275 

FSV-BA 0.654 0.452 0.608 0.431 1.050 0.012 0.067 0.003 0.062 0.053 6.38 6.84 5.94 6.53 6.89 2.61 2.01 2.40 1.91 2.55 

FSV-BB 0.657 0.455 0.602 0.432 1.049 0.024 0.049 0.024 0.045 0.034 6.41 7.08 5.98 6.78 7.12 2.34 1.91 2.20 1.80 2.28 

FSV-BD 0.624 0.435 0.607 0.429 1.043 6.00 5.50 5.40 6.20 6.50 

FSV-BE 0.670 0.470 0.670 0.420 1.120 6.50 7.30 6.50 6.90 7.50 2.40 2.00 2.40 1.80 2.40 

FSV-BF 0.671 0.464 0.629 0.460 1.121 5.97 7.38 6.16 7.37 8.04 2.19 1.90 2.20 1.90 2.46 

FSV-BG 0.634 0.485 0.622 0.443 1.145 0.043 0.083 0.049 0.054 0.047 5.56 7.03 5.63 6.56 6.86 2.04 1.89 2.00 1.67 2.27 

FSV-BH 0.745 0.524 0.720 0.522 1.200 6.59 7.45 6.27 7.04 7.69 2.30 1.92 2.17 1.83 2.31 

FSV-BI 0.664 0.460 0.618 0.440 1.119 6.06 7.00 5.61 6.70 7.13 2.33 2.04 2.16 1.93 2.38 

FSV-BJ >0.638 >0.452 >0.632 >0.452 >1.077 0.638 0.452 0.632 0.452 1.077 nq 0.054 nq 0.055 nq 5.60 6.88 5.53 6.59 6.88 2.26 1.98 2.21 1.89 2.43 

FSV-BK 0.630 0.440 0.592 0.412 1.071 4.60 5.65 4.40 5.15 5.58 

FSV-BL 0.740 0.490 0.690 0.490 1.000 6.89 7.97 6.72 7.54 8.14 

FSV-BM 0.665 0.483 0.671 0.465 1.113 6.96 7.70 6.22 6.93 7.50 

FSV-BN 0.743 0.510 0.617 0.450 1.159 0.017 0.037 0.017 0.045 0.023 5.70 6.34 4.79 5.73 6.39 2.00 1.55 1.65 1.49 1.99 0.140 0.153 0

FSV-BO 0.713 0.484 0.581 0.444 1.054 6.00 6.60 5.80 6.90 6.80 

FSV-BP 0.675 0.464 0.636 0.451 1.033 7.61 6.90 5.69 6.22 6.70 

FSV-BQ 0.700 0.500 0.680 0.490 1.100 6.00 6.70 5.80 6.30 6.70 

FSV-BR >0.62 >0.45 >0.61 >0.44 >1.06 0.62 0.45 0.61 0.44 1.06 5.77 6.71 5.61 6.32 7.27 

FSV-BU 0.585 0.384 0.540 0.351 1.022 4.88 5.78 4.41 5.47 5.69 2.36 2.04 2.09 1.81 2.20 

FSV-BV 0.684 0.470 0.567 0.472 0.958 6.64 7.15 6.20 6.41 6.76 2.40 1.93 2.30 1.82 2.26 

FSV-BW 0.710 0.500 0.680 0.480 1.190 0.023 0.066 0.021 0.055 0.030 6.45 7.54 6.10 7.07 7.50 2.26 1.90 2.12 1.79 2.29 

FSV-BX >0.647 >0.463 >0.659 >0.436 >1.083 0.647 0.463 0.659 0.436 1.083 6.30 7.22 6.16 6.75 7.14 2.20 1.83 2.21 1.72 2.32 

FSV-CB 0.614 0.419 0.593 0.412 0.987 5.84 6.42 5.51 6.20 6.46 

FSV-CC 0.720 0.510 0.710 0.480 1.150 0.710 0.500 0.700 0.470 1.140 6.80 7.10 6.10 6.70 7.20 

FSV-CD >0.661 >0.464 >0.633 >0.434 >1.116 0.661 0.464 0.633 0.434 1.116 0.035 0.098 0.028 0.091 0.037 6.09 6.75 5.66 6.36 7.03 2.39 1.95 2.21 1.88 2.31 

FSV-CE 0.568 0.394 0.570 0.384 0.986 5.58 6.27 5.32 5.95 6.42 

FSV-CF 0.665 0.465 0.642 0.432 1.050 7.00 7.60 6.60 7.00 7.20 

FSV-CG 0.705 0.495 0.682 0.497 1.099 5.57 6.26 5.11 5.72 5.33 2.54 2.09 2.32 1.94 2.45 0.283 0.340 0

FSV-CH 0.580 0.378 0.521 0.361 0.847 6.01 6.49 5.42 6.19 5.88 1.98 1.59 1.84 1.56 1.72 

FSV-CI 0.800 0.540 0.750 0.520 1.060 0.030 0.050 0.020 0.040 0.040 6.92 7.51 6.49 7.13 8.56 2.38 2.10 2.27 1.97 2.61 

FSV-CK 0.670 0.470 0.700 0.510 1.190 6.03 7.12 6.58 7.52 8.04 2.63 2.20 2.67 2.20 2.95 

FSV-CL 0.444 0.330 0.437 0.316 0.668 8.75 10.08 8.31 9.14 8.68 2.67 2.21 3.02 2.06 2.58 

FSV-CR 0.720 0.580 0.700 0.500 1.160 5.70 7.80 5.60 7.10 6.60 

FSV-CV 0.510 !0.88 0.467 0.217 1.463 0.050 0.050 nd 0.020 0.030 7.18 7.97 6.50 7.93 8.05 2.27 1.88 2.10 1.91 2.34 0.101 0.338 0

FSV-CW >0.587 >0.397 >0.554 >0.387 >0.945 0.587 0.397 0.554 0.387 0.945 0.016 0.048 0.015 0.045 0.020 7.35 8.32 6.83 7.98 8.21 2.47 2.06 2.31 1.99 2.42 0.090 0.110 0

FSV-CX >0.59 >0.40 >0.56 >0.38 >0.89 0.59 0.40 0.56 0.38 0.89 6.55 7.36 6.24 6.91 7.21 

FSV-CZ 0.700 0.470 0.650 0.460 1.210 2.40 2.70 2.20 2.60 2.80 

FSV-DB 0.640 0.470 0.620 0.460 1.110 6.74 7.98 6.25 7.71 7.15 

FSV-DD >0.715 >0.486 >0.639 >0.322 >1.072 0.715 0.486 0.639 0.322 1.072 

FSV-DF 0.660 0.470 0.620 0.440 1.096 

FSV-DI 0.688 0.469 0.660 0.452 1.091 0.015 0.038 0.010 0.048 0.020 7.30 8.30 7.19 8.16 8.59 2.30 1.89 2.25 1.84 2.38 0.129 0.156 0

FSV-DQ 6.58 7.15 5.88 6.42 6.62 2.66 1.96 2.24 1.81 2.32 

FSV-DR 0.610 0.420 0.560 0.400 1.090 5.96 6.67 5.59 6.65 6.47 

FSV-DU !0.93 0.510 0.690 0.470 1.120 !6.78 6.44 5.50 6.24 6.24 

FSV-EH 0.585 0.415 0.568 0.400 0.944 0.035 0.058 0.033 0.056 0.032 6.26 7.03 5.79 6.36 9.34 1.96 1.83 2.10 1.65 2.86 0.133 0.121 0

FSV-EQ 0.619 0.442 0.578 0.386 1.036 5.72 6.86 5.42 5.91 7.00 

FSV-FB 0.680 0.490 0.690 0.480 1.250 7.33 7.65 6.73 7.39 8.02 

FSV-FJ 0.700 0.500 0.670 0.480 1.190 7.33 8.38 6.92 8.51 8.55 2.31 2.00 2.22 1.92 2.36 

N 38 38 39 39 39 8 8 8 8 8 11 12 10 12 11 44 45 45 45 45 25 25 25 25 25 6 6 

Min 0.444 0.330 0.437 0.217 0.668 0.587 0.397 0.554 0.322 0.890 0.012 0.037 0.003 0.020 0.020 2.40 2.70 2.20 2.60 2.80 1.96 1.55 1.65 1.49 1.72 0.090 0.110 0

Median 0.668 0.470 0.622 0.450 1.096 0.642 0.457 0.633 0.435 1.074 0.024 0.052 0.021 0.051 0.032 6.28 7.08 5.88 6.70 7.12 2.33 1.95 2.21 1.84 2.36 0.131 0.155 0

Max 0.800 0.580 0.750 0.522 1.463 0.715 0.500 0.700 0.470 1.140 0.050 0.098 0.049 0.091 0.053 8.75 10.08 8.31 9.14 9.34 2.67 2.21 3.02 2.20 2.95 0.283 0.340 0

SD 0.055 0.037 0.069 0.047 0.080 0.045 0.024 0.034 0.043 0.054 0.014 0.013 0.009 0.008 0.009 0.74 0.65 0.55 0.64 0.81 0.12 0.11 0.13 0.09 0.12 0.022 0.121 0

CV 8 8 11 11 7 7 5 5 10 5 57 25 42 15 28 12 9 9 10 11 5 6 6 5 5 17 79 

Npast 44 35 35 44 45 11 12 12 11 0 11 14 12 15 8 52 44 44 52 45 29 25 25 29 21 6 7 

Medianpast 0.663 0.470 0.650 0.446 1.079 0.668 0.445 0.603 0.440 0.028 0.057 0.027 0.053 0.053 6.32 7.12 6.00 6.81 7.14 2.34 2.01 2.30 1.85 2.45 0.121 0.118 0

SDpast 0.081 0.051 0.050 0.045 0.106 0.033 0.023 0.031 0.030 0.014 0.014 0.013 0.014 0.035 0.64 0.58 0.54 0.68 0.55 0.27 0.16 0.19 0.15 0.27 0.201 0.065 0

NISTa 

NISTb 

NNIST 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 1 

Mean 0.624 0.441 0.599 0.435 1.016 0.624 0.441 0.599 0.435 0.959 5.83 6.88 5.75 6.41 6.88 2.22 1.91 2.10 1.71 2.25 0.214 0

0.641 0.448 0.631 0.460 1.068 0.641 0.448 0.631 0.460 1.019 

0.607 0.435 0.569 0.411 0.970 0.607 0.435 0.569 0.411 0.909 

5.49 6.55 5.49 6.65 6.87 2.14 1.76 1.92 1.63 2.12 

6.25 7.21 6.06 6.17 6.89 2.31 2.06 2.27 1.80 2.37 nq 0.214 0

Srep 0.005 0.012 0.007 0.019 0.026 0.005 0.012 0.007 0.019 0.027 0.16 0.16 0.14 0.12 0.28 0.14 0.06 0.07 0.06 0.13 0.032 0

Shet 0.006 0.017 0.006 0.022 0.019 0.006 0.017 0.006 0.022 0.033 0.25 0.13 0.16 0.48 0.15 0.05 0.10 0.04 0.07 0.09 

Sanl 0.025 0.009 0.042 0.035 0.073 0.025 0.009 0.042 0.035 0.086 0.48 0.47 0.45 0.34 0.02 0.11 0.21 0.24 0.11 0.18 

SNIST 0.026 0.023 0.043 0.046 0.080 0.026 0.023 0.043 0.046 0.096 0.56 0.51 0.50 0.60 0.32 0.18 0.24 0.25 0.15 0.24 

NAV 

NAU 

0.646 0.456 0.610 0.443 1.056 

0.063 0.043 0.071 0.049 0.101 

0.631 0.447 0.615 0.436 1.018 

0.052 0.037 0.055 0.046 0.127 

0.024 0.052 0.021 0.051 0.032 

0.017 0.021 0.017 0.021 0.018 

6.05 6.98 5.81 6.55 7.00 

0.81 0.66 0.55 0.67 0.83 

2.27 1.93 2.15 1.78 2.30 

0.25 0.25 0.26 0.21 0.25 

0.126 0.184 0

0.101 0.128 0

All Lab Report 
Round Robin L Laboratory Results
 

All Results in μg/mL
 

Total β-Carotene trans-β-Carotene Total cis-β-Carotene Total α-Carotene trans-α-Caroten

C3

Lab 274 275 276 277 278 274 275 276 277 278 274 275 276 277 278 274 275 276 277 278 274 275 276 27

FSV-BA 0.498 0.313 0.449 0.304 0.492 0.294 0.425 0.286 0.458 0.476 0.022 0.019 0.024 0.018 0.033 0.024 0.020 0.024 0.016 0.019 

FSV-BB 0.500 0.331 0.452 0.318 0.534 0.314 0.435 0.301 0.509 0.481 0.019 0.017 0.017 0.017 0.025 0.030 0.017 0.030 0.009 0.024 

FSV-BD 

FSV-BE 0.478 0.349 0.471 0.327 0.530 

FSV-BF 0.583 0.405 0.632 0.407 0.790 0.024 0.013 0.027 0.009 0.011 

FSV-BG 0.513 0.362 0.474 0.313 0.518 0.038 0.022 0.029 0.024 0.022 

FSV-BH 0.619 0.450 0.589 0.411 0.683 0.410 0.547 0.374 0.624 0.581 0.038 0.040 0.042 0.037 0.059 0.040 0.016 0.025 0.012
 0.017 

FSV-BI
 0.525 0.348 0.493 0.331 0.557 0.035 0.020 0.033 0.016
 0.022 

FSV-BJ
 0.573 0.357 0.546 0.323 0.578 0.038 0.025 0.038 0.016 0.025 

FSV-BK 

FSV-BL 

FSV-BM 

FSV-BN 0.560 0.364 0.461 0.325 0.588 0.337 0.435 0.304 0.544 0.528 0.032 0.027 0.026 0.021 0.044 0.028 0.014 0.024 0.015 0.019 

FSV-BO 0.509 0.369 0.472 0.353 0.641 0.037 0.024 0.039 0.021 0.032 

FSV-BP 0.549 0.383 0.495 0.346 0.565 0.025 0.015 0.020 0.023 0.017 

FSV-BQ 

FSV-BR 

FSV-BU 0.576 0.359 0.502 0.400 0.596 0.032 0.025 0.033 0.022 0.026 

FSV-BV 0.542 0.349 0.498 0.340 0.552 0.024 0.015 0.023 0.012 0.017 

FSV-BW 0.540 0.360 0.510 0.330 0.560 0.041 0.023 0.038 0.030 0.024 

FSV-BX >0.498 >0.336 >0.483 >0.313 >0.522 0.336 0.483 0.313 0.522 0.498 0.033 0.023 0.033 0.021 0.023 

FSV-CB 0.508 0.351 0.473 0.340 0.535 0.024 0.014 0.023 0.011 0.015 

FSV-CC 

FSV-CD 0.522 0.331 0.509 0.310 0.566 0.031 0.019 0.027 0.013 0.018 

FSV-CE 0.487 0.311 0.438 0.308 0.491 

FSV-CF 

FSV-CG 0.580 0.393 0.529 0.360 0.618 0.365 0.498 0.335 0.571 0.548 0.031 0.028 0.030 0.026 0.041 0.035 0.021 0.032 0.021 0.024 

FSV-CH 0.466 0.283 0.425 0.292 0.427 0.024 0.016 0.023 0.012 0.014 

FSV-CI 

FSV-CK 0.447 0.434 0.631 0.516 0.859 0.052 0.034 0.062 0.030
 0.027 

FSV-CL
 0.430 0.286 0.399 0.279 0.434 0.023 0.016 0.022 0.011 0.015 

FSV-CR 

FSV-CV 0.568 0.386 0.593 0.388 0.741 0.063 0.024 0.051 0.169 0.032 

FSV-CW 0.512 0.346 0.485 0.338 0.526 0.324 0.460 0.313 0.492 0.488 0.024 0.022 0.025 0.025 0.034 0.031 0.022 0.031 0.017 0.023 

FSV-CX >0.36 >0.24 >0.34 >0.21 >0.37 0.240 0.340 0.210 0.370 0.360 >0.02 >0.02 >0.02 >0.02 >0.02 0.020 0.020 0.0

0.020 

FSV-CZ 0.600 0.440 0.560 0.430 0.680 

FSV-DB 0.360 0.210 0.360 0.260 0.420 

FSV-DD 

FSV-DF 

FSV-DI >0.508 >0.319 >0.509 >0.342 >0.512 0.319 0.509 0.342 0.512 0.508 

FSV-DQ 0.550 0.347 0.508 0.307 0.547 0.036 0.025 0.036 0.019 0.025 

FSV-DR 0.410 0.300 0.400 0.280 0.590 

FSV-DU >0.25 >0.37 >0.24 >0.55 !0.40 0.25 0.37 0.24 0.55 

FSV-EH 0.424 0.299 0.406 0.297 0.447 0.274 0.377 0.265 0.408 0.395 0.029 0.025 0.029 0.032 0.039 0.036 0.015 0.036 0.014 0.021 

FSV-EQ 0.493 0.316 0.453 0.304 0.506 0.309 0.447 0.295 0.495 0.487 0.006 0.007 0.006 0.009 0.011 0.020 0.012 0.019 0.010
 0.013 

FSV-FB
 0.606 0.414 0.560 0.393 0.659 0.314 0.431 0.296 0.475 0.464 0.142 0.099 0.129 0.097 0.185 0.030 0.020 0.027 0.016
 0.018 

FSV-FJ
 1.270 0.910 1.310 0.780 1.380 0.060 0.030 0.050 0.010 0.030 

N 

Min 

Median 

Max 

SD 

CV 

Npast 

Medianpast 

SDpast 

NISTa 

NISTb 

NNIST 

Mean 

Srep 

Shet 

Sanl 

SNIST 

31 

0.360 

0.522 

1.270 

0.060 

11 

33 

0.508 

0.069 

3 

0.503 

0.009 

0.019 

0.100 

0.102 

31 

0.210 

0.351 

0.910 

0.045 

13 

32 

0.352 

0.035 

3 

0.345 

0.007 

0.001 

0.042 

0.043 

31 

0.360 

0.493 

1.310 

0.063 

13 

32 

0.499 

0.046 

3 

0.470 

0.011 

0.011 

0.074 

0.076 

31 

0.260 

0.330 

0.780 

0.049 

15 

33 

0.307 

0.063 

3 

0.325 

0.007 

0.005 

0.032 

0.033 

31 

0.420 

0.560 

1.380 

0.080 

14 

33 

0.582 

0.078 

3 

0.537 

0.010 

0.008 

0.036 

0.038 

12 13 13 13 13 

0.240 0.340 0.210 0.370 0.360 

0.314 0.435 0.301 0.509 0.488 

0.410 0.547 0.374 0.624 0.581 

0.031 0.043 0.020 0.051 0.030 

6 10 10 7 10 

17 14 14 17 11 

0.316 0.442 0.287 0.535 0.470 

0.025 0.034 0.041 0.065 0.047 

2 2 2 2 2 

0.345 0.494 0.292 0.517 0.528 

0.015 0.020 0.016 0.006 0.008 

0.004 0.003 0.022 0.003 0.013 

0.015 0.020 0.027 0.007 0.015 

9 

0.006 

0.029 

0.142 

0.007 

26 

11 

0.024 

0.008 

9 

0.007 

0.025 

0.099 

0.007 

27 

10 

0.023 

0.005 

9 

0.006 

0.026 

0.129 

0.004 

17 

10 

0.025 

0.004 

9 

0.009 

0.025 

0.097 

0.010 

42 

11 

0.020 

0.006 

9 

0.011 

0.039 

0.185 

0.008 

21 

8 

0.041 

0.027 

27 27 27 27 27 

0.020 0.012 0.019 0.009 0.011 

0.032 0.020 0.030 0.016 0.022 

0.063 0.034 0.062 0.169 0.032 

0.010 0.006 0.009 0.007 0.005 

25 31 30 30 42 

28 24 23 29 22 

0.029 0.018 0.030 0.017 0.021 

0.007 0.004 0.007 0.008 0.006 

3 1 3 1 

0.021 0.031 0.022 0.034 

0.002 0.001 0.003 0.003 

0.001 0.001 

0.003 0.002 

0.004 0.003 

1 1 1 

0.020 0.020 0.00.020 

0 0 0 

2 2 2 

0.026 0.017 0.00.016 

0.000 0.001 0.00.003 

0.001 0.001 0.00.001 

0.001 0.002 0.00.003 

0.432 0.316 0.422 0.302 0.511 

0.574 0.375 0.523 0.348 0.562 0.531 0.345 0.494 0.292 0.518 0.043 0.031 0.029 0.056 0.044 

nq 0.036 nq 0.029 nq 

>0.016 0.032 0.021 0.032 0.022 0.016 0.026 0.017 0.0

NAV 

NAU 

0.513 0.348 0.482 0.327 0.548 0.508 0.329 0.464 0.296 0.513 0.027 0.024 0.026 0.023 0.040 0.022 0.033 0.021 0.030 0.019 

0.103 0.050 0.077 0.049 0.081 0.059 0.040 0.062 0.033 0.054 0.006 0.004 0.003 0.006 0.014 0.008 0.011 0.007 0.010 0.008 

All Lab Report 
Round Robin L Laboratory Results
 

All Results in μg/mL
 

Total Lycopene trans-Lycopene Total β-Cryptoxanthin Total α-Cryptoxanthin Total Lutein 

C4

Lab 274 275 276 277 278 274 275 276 277 278 274 275 276 277 278 274 275 276 277 278 274 275 276 277 278 274 

FSV-BA 0.185 0.129 0.181 0.333 0.144 0.076 0.069 0.081 0.062 0.078 

FSV-BB 0.330 0.207 0.311 0.572 0.222 0.152 0.107 0.141 0.273 0.117 0.055 0.049 0.052 0.049 0.052 0.025 0.023 0.023 0.019 0.024 0.102 0.092 0.092 0.088 0.077 

FSV-BD 

FSV-BE 

FSV-BF 0.374 0.208 0.386 0.768 0.199 0.042 0.036 0.043 0.040 0.035 

FSV-BG 0.362 0.192 0.252 0.549 0.227 0.208 0.126 0.143 0.335 0.130 0.045 0.042 0.043 0.048 0.046 0.081 0.089 0.083 0.086 0.089 

FSV-BH 0.337 0.207 0.307 0.542 0.223 0.090 0.073 0.086 0.090
 0.078 

FSV-BI
 0.281 0.172 0.256 0.509 0.183 0.065 0.056 0.062 0.048 0.062 0.092 0.104 0.085 0.097 0.081
 

FSV-BJ
 0.290 0.179 0.263 0.493 0.212 0.053 0.051 0.055 0.048 0.051 0.080 0.074 0.076 0.074 0.065 

FSV-BK 

FSV-BL 

FSV-BM 

FSV-BN 0.456 0.267 0.425 0.823 0.313 0.239 0.146 0.226 0.470 0.175 0.060 0.049 0.057 0.052 0.061 0.024 0.021 0.023 0.018 0.027 0.112 0.104 0.092 0.098 0.087 

FSV-BO 0.368 0.237 0.227 0.722 0.270 0.045 0.042 0.045 0.047 0.044 0.147 0.144 0.132 0.144 0.139 

FSV-BP 0.407 0.276 0.363 0.632 0.297 0.055 0.049 0.050 0.047 0.057 

FSV-BQ 

FSV-BR 

FSV-BU 0.291 0.178 0.281 0.512 0.201 0.048 0.044 0.045 0.041 0.046 

FSV-BV 0.343 0.217 0.335 0.567 0.238 0.033 0.030 0.031 0.027 0.032 

FSV-BW 0.370 0.230 0.340 0.650 0.230 

FSV-BX 0.155 0.113 0.151 0.290 0.120 0.045 0.044 0.042 0.041 0.045 0.095 0.084 0.097 0.081 0.069 

FSV-CB 0.308 0.184 0.302 0.524 0.198 0.049 0.044 0.048 0.045 0.047 0.094 0.079 0.072 0.072 

FSV-CC 

FSV-CD 0.299 0.220 0.280 0.491 0.229 0.047 0.043 0.044 0.056 0.043 

FSV-CE 

FSV-CF 

FSV-CG 0.353 0.213 0.323 0.569 0.234 0.177 0.117 0.160 0.306 0.132 0.047 0.038 0.043 0.044 0.042 0.130 0.115 0.119 0.107 0.106 

FSV-CH 0.266 0.180 0.253 0.404 0.181 

FSV-CI 

FSV-CK 0.328 0.264 0.376 0.697 0.173 0.081 0.059 0.063 0.064 0.048 0.042 0.038 0.044 0.043 0.046 0.099 0.099 0.099 0.099 0.083
 

FSV-CL
 0.318 0.200 0.305 0.501 0.220 0.048 0.045 0.049 0.037 0.047 0.026 0.024 0.026 0.019 0.026 

FSV-CR 

FSV-CV 0.473 0.312 0.490 0.927 0.304 

FSV-CW 0.346 0.215 0.332 0.553 0.222 0.164 0.113 0.155 0.287 0.123 0.053 0.046 0.051 0.049 0.049 0.025 0.022 0.024 0.021 0.024 >0.084 >0.08 >0.079 >0.076 >0.061 0

0.084 

FSV-CX 0.270 0.170 0.250 0.460 0.180 0.140 0.100 0.130 0.250 0.110 0.060 0.050 0.050 0.040 0.050 0.070 0.070 0.070 0.070 0.060 

FSV-CZ 

FSV-DB 0.321 0.204 0.334 0.541 0.207 0.056 0.046 0.052 0.045 0.056 

FSV-DD 

FSV-DF 

FSV-DI 0.241 0.165 0.247 0.403 0.172 0.095 0.089 0.092 0.085 0.078 

FSV-DQ 0.402 0.236 0.366 0.599 0.280 0.063 0.061 0.059 0.054 0.065 0.095 0.108 0.102 0.102 0.095 

FSV-DR 

FSV-DU 

FSV-EH 0.359 0.226 0.349 0.622 0.230 0.193 0.120 0.206 0.373 0.124 0.059 0.051 0.054 0.052 0.048 0.088 0.081 0.084 0.079 0.071 

FSV-EQ 0.337 0.213 0.330 0.573 0.231 0.056 0.047 0.055 0.056 0.050 

FSV-FB 0.340 0.220 0.320 0.580 0.210 0.287 0.187 0.270 0.491 0.176 0.059 0.053 0.054 0.051 0.059 0.064 0.066 0.060 0.060 0.060
 

FSV-FJ
 

N 26 26 26 26 26 11 11 11 11 11 25 25 25 25 25 5 5 5 5 5 15 15 15 14 15 1 

Min 0.173 0.266 0.170 0.227 0.404 0.110 0.140 0.100 0.130 0.250 0.032 0.033 0.030 0.031 0.027 0.024 0.024 0.021 0.023 0.018 0.064 0.066 0.060 0.060 0.060 

Median 0.223 0.339 0.213 0.322 0.568 0.130 0.185 0.120 0.160 0.333 0.049 0.055 0.047 0.051 0.048 0.026 0.025 0.023 0.024 0.019 0.095 0.089 0.092 0.087 0.078 0.084 0

Max 0.313 0.473 0.312 0.490 0.927 0.176 0.287 0.187 0.270 0.491 0.078 0.090 0.073 0.086 0.090 0.046 0.042 0.038 0.044 0.043 0.147 0.144 0.132 0.144 0.139 

SD 0.023 0.042 0.026 0.049 0.085 0.027 0.048 0.018 0.051 0.074 0.008 0.010 0.005 0.008 0.006 0.002 0.001 0.001 0.002 0.001 0.012 0.018 0.014 0.014 0.013 

CV 10 12 12 15 15 21 26 15 32 22 17 18 12 15 12 9 5 6 9 8 13 20 15 16 17 

Npast 29 27 27 29 24 12 12 12 12 11 29 25 25 29 20 7 5 5 7 9 16 15 15 16 14 0 

Medianpast 0.228 0.363 0.230 0.330 0.575 0.135 0.189 0.124 0.165 0.380 0.050 0.057 0.051 0.054 0.061 0.029 0.027 0.024 0.026 0.027 0.092 0.089 0.088 0.083 0.083 

SDpast 0.042 0.046 0.037 0.057 0.135 0.018 0.042 0.032 0.015 0.083 0.010 0.007 0.013 0.014 0.016 0.006 0.007 0.009 0.007 0.009 0.017 0.025 0.029 0.012 0.024 

NISTa
 

NISTb
 0.370 0.227 0.334 0.621 0.288 

NNIST 2 2 2 2 2 4 3 3 3 3 2 1 1 1 1 4 4 4 4 4 2 

Mean 0.282 0.370 0.227 0.330 0.620 

0.048 0.046 0.048 0.042 0.044 

0.040 0.052 0.048 0.047 0.046 0.016 0.030 0.030 0.029 0.024 0.091 0.087 0.080 0.091 0.077 0.073 0

0.108 0.094 0.087 0.107 0.086 

0.065 0.058 0.049 0.052 0.047 0.032 0.030 0.030 0.029 0.024 >0.076 >0.080 >0.073 >0.075 >0.069 0.076 0

Srep 0.010 0.006 0.031 0.001 0.015 0.004 0.003 0.004 0.004 0.005 0.003 0.002 0.004 0.000 0.007 0.004 0.004 0.004 0.003 0.006 0.000 0

Shet 0.024 0.004 0.029 0.015 0.001 0.032 0.001 0.002 0.000 0.003 0.023 0.007 0.001 0.003 0.004 0.009 0.010 0

Sanl 0.011 0.009 0.001 0.007 0.002 0.024 0.010 0.010 0.022 0.013 

SNIST 0.026 0.007 0.043 0.015 0.015 0.034 0.009 0.005 0.008 0.006 0.023 0.026 0.011 0.011 0.022 0.017 0.010 0

0.027 0.026 0.026 0.023 0.024 0.093 0.088 0.086 0.089 0.077 

0.003 0.004 0.003 0.004 0.004 0.026 0.018 0.020 0.023 0.017 

NAV 

NAU 

0.252 0.354 0.220 0.326 0.594 0.130 0.185 0.120 0.160 0.333 0.045 0.053 0.048 0.049 0.047 

0.068 0.078 0.053 0.072 0.121 0.027 0.048 0.021 0.051 0.074 0.035 0.013 0.012 0.013 0.012 

All Lab Report 
Round Robin L Laboratory Results
 

All Results in μg/mL
 

Total Zeaxanthin Total Lutein&Zeaxanthin Coenzyme Q10 Phylloquinone (K1) x1000 

C5

Lab 274 275 276 277 278 274 275 276 277 278 274 275 276 277 278 274 275 276 277 278 

FSV-BA 0.187 0.186 0.166 0.181 0.136 

FSV-BB 0.046 0.037 0.040 0.037 0.048 0.148 0.129 0.132 0.125 0.125 

FSV-BD 

FSV-BE 0.44 1.04 0.40 0.30 1.24 

FSV-BF 0.138 0.131 0.128 0.122 0.119 

FSV-BG 0.030 0.024 0.026 0.021 0.024 0.101 0.102 0.098 0.098 0.104 

FSV-BH 

FSV-BI 0.039 0.031 0.036 0.029 0.035 0.131 0.135 0.121 0.126 0.116 

FSV-BJ 0.545 0.551 0.480 0.733 0.546 

FSV-BK 

FSV-BL 

FSV-BM 

FSV-BN 0.050 0.030 0.042 0.030 0.034 0.160 0.134 0.133 0.127 0.120 

FSV-BO 0.044 0.036 0.042 0.021 0.053 0.191 0.180 0.174 0.165 0.192 

FSV-BP 0.160 0.140 0.140 0.140 0.120 

FSV-BQ 

FSV-BR 

FSV-BU 0.082 0.120 0.132 0.117 0.110 

FSV-BV 0.120 0.100 0.112 0.095 0.089 

FSV-BW 

FSV-BX 0.031 0.024 0.030 0.021 0.024 0.127 0.108 0.128 0.102 0.093 

FSV-CB 0.039 0.025 0.034 0.034 0.134 0.104 0.106 0.124 0.106 

FSV-CC 

FSV-CD 0.117 0.110 0.117 0.105 0.098 

FSV-CE 

FSV-CF 

FSV-CG 0.020 0.020 0.018 0.017 0.018 0.150 0.135 0.137 0.124 0.124 

FSV-CH 0.562 0.415 0.572 0.449
 0.545 

FSV-CI
 0.19 0.59 0.20 0.10 0.59 

FSV-CK 0.041 0.031 0.041 0.032 0.038 0.129 0.128 0.141 0.134 0.135
 

FSV-CL
 0.113 0.099 0.102 0.089 0.079 

FSV-CR 

FSV-CV 0.116 0.109 0.107 0.108 0.096 0.873 0.830 0.947 0.935 0.683 

FSV-CW 0.039 0.028 0.037 0.027 0.031 >0.123 >0.108 >0.116 >0.103 >0.092 0.940 0.830 0.910 0.960 0.860 

FSV-CX 0.040 0.030 0.040 0.030 0.040 0.110 0.100 0.110 0.100 0.100 

FSV-CZ 0.990 0.930 0.920 1.030 1.090 

FSV-DB 0.128 0.117 0.123 0.108 0.100 

FSV-DD 

FSV-DF 

FSV-DI 0.480 0.517 0.609 0.549 0.420 0.28 1.10 0.32 0.11 1.07 

FSV-DQ 0.036 0.023 0.029 0.020 0.023 0.131 0.131 0.131 0.122 0.118 

FSV-DR 

FSV-DU 

FSV-EH 0.026 0.022 0.026 0.020 0.021 0.114 0.103 0.110 0.099 0.092 0.960 0.845 0.858 1.043 0.882 

FSV-EQ 0.208 0.205 0.197 0.198 0.218
 

FSV-FB
 0.033 0.025 0.031 0.022 0.030 0.097 0.091 0.091 0.082 0.090
 

FSV-FJ
 

NISTa 

NISTb 

NNIST 

0.031 0.015 0.026 nq 0.028 0.139 0.109 0.113 >0.107 0.114 

>0.043 >0.036 >0.037 >0.035 >0.044 >0.119 >0.115 >0.110 >0.110 >0.113 

4 4 4 2 4 4 4 4 2 4 

N 14 14 14 13 14 23 23 23 23 23 7 7 7 7 7 3 3 3 3 3 

Min 0.020 0.020 0.018 0.017 0.018 0.082 0.091 0.091 0.082 0.079 0.420 0.480 0.415 0.480 0.449 0.59 0.19 0.59 0.20 0.10 

Median 0.039 0.027 0.035 0.022 0.032 0.129 0.120 0.128 0.122 0.110 0.683 0.873 0.830 0.858 0.935 1.07 0.28 1.04 0.32 0.11 

Max 0.050 0.037 0.042 0.037 0.053 0.208 0.205 0.197 0.198 0.218 1.090 0.990 0.930 0.947 1.043 1.24 0.44 1.10 0.40 0.30 

SD 0.007 0.005 0.008 0.007 0.010 0.025 0.023 0.019 0.019 0.019 0.242 0.294 0.225 0.241 0.263 

CV 17 20 23 31 30 20 19 15 15 17 35 34 27 28 28 

Npast 15 13 13 15 10 29 22 22 29 16 0 5 5 0 0 0 0 0 0 0 

Medianpast 0.035 0.024 0.034 0.027 0.034 0.133 0.121 0.132 0.114 0.117 0.950 0.830 

SDpast 0.009 0.006 0.007 0.005 0.011 0.025 0.027 0.029 0.017 0.030 0.151 0.162 

Mean 0.036 0.025 0.031 0.035 0.037 0.127 0.112 0.111 0.110 0.113
 

Srep 0.003 0.003 0.003 0.007 0.002 0.006 0.003 0.005 0.010 0.009
 

Shet 0.007 0.002 0.002 0.001 0.004 0.015 0.002 0.006 0.003 0.008
 

Sanl 0.007 0.015 0.008 0.012 0.017 0.005 0.002 0.001
 

SNIST 0.011 0.015 0.009 0.007 0.013 0.024 0.006 0.008 0.010 0.012 

NAV 

NAU 

0.038 0.026 0.033 0.028 0.034 0.128 0.116 0.120 0.116 0.112 0.683 0.912 0.830 0.858 0.935 

0.011 0.015 0.010 0.011 0.014 0.027 0.025 0.029 0.027 0.023 0.242 0.166 0.139 0.241 0.263 

All Lab Report 
 

 

 

 

 

Round Robin L Laboratory Results
 

All Results in μg/mL
 

Analytes Reported By One Laboratory 

Term 

N 

Min 

Medianpart 

Max 

SD 

CV 

Npast 

Medianpast 

SDpast 

NISTa, NISTb 

NNIST 

MeanNIST 

Srep 

Shet 

Sanl 

SNIST 

NAV 

NAU 

nd 

nq 

>x 

!

italics

Analyte Code 274 275 276 277 278 

trans-β-Cryptoxanthin NISTb 0.047 0.053 0.048 0.042 0.0160 

trans-Zeaxanthin NISTb 0.043 0.036 0.037 0.035 0.076 

trans-Lutein&Zeaxanthin NISTb 0.119 0.115 0.110 0.110 0.037 

9-cis-β-Carotene FSV-FB 0.02 0.02 0.02 0.02 0.14 

13-cis-β-Carotene FSV-FB 0.12 0.08 0.11 0.08 0.04 

Phytofluene FSV-CL 0.011 0.032 0.010 0.030 0.113 

Phytoene FSV-CL 0.059 0.079 0.058 0.077 0.044 

25-hydroxyvitamin D FSV-BN 0.0073 0.0079 0.0258 nq 0.041 

Legend 

Definition

 Number of (non-NIST) quantitative values reported for this analyte

 Minimum (non-NIST) quantitative value reported

 Median (non-NIST) quantitative value reported 

 Maximum (non-NIST) quantitative value reported

 Standard deviation for (non-NIST) results: 0.741*(3rd Quartile - 1st Quartile)

 Coefficient of Variation for (non-NIST) results: 100*SD/Median

 Mean of N(s) from past RR(s)

 Mean of Median(s) from past RR(s)

 Pooled SD from past RR(s)
 

 Mean of all analyses (vials x duplicates) reported by given NIST analyst

 Number of total vials analyzed in duplicate by NIST analysts

 Mean of the NIST-analyzed vial means

 W ithin-vial pooled standard deviation

 Among-vial pooled standard deviation

 Between NIST analyst standard deviation

2

)

0.5 Total standard deviation for NIST analyses: (Srep 2

 + Shet 2 + Sanl 

 NIST Assigned Value

 = (Medianpart + MeanNIST)/2 for analytes reported by NIST analyst(s)

 = Medianpart for analytes reported by ≥ 10 labs but not NIST

2

)

0.5 NIST Assigned Uncertainty: (S2

 + Sbtw 

 S is the maximum of (0.05*NAV, SD, SNIST, eSD) and Sbtw is the standard

 deviation between Medianpart and MeanNIST. The expected long-term SD, eSD,

 is defined in: Duewer, et al. Anal Chem 1997;69(7):1406-1413.

 Not detected (i.e., no detectable peak for analyte)

 Detected but not quantitatively determined

 Concentration greater than x

 Non-quantitative value: heterogeneous serum, damaged sample, malfunction, etc.
 

 Not explicitly reported but calculated by NIST from reported values
 

All Lab Report Page 5 / 6 

C6
 

 

 

 

 

 

Lab 

FSV-BA 

FSV-BB 

FSV-BD 

FSV-BE 

FSV-BF 

FSV-BG 

FSV-BH 

FSV-BI 

FSV-BJ 

FSV-BK 

FSV-BL 

FSV-BM 

FSV-BN 

FSV-BO 

FSV-BP 

FSV-BQ 

FSV-BR 

FSV-BU 

FSV-BV 

FSV-BW 

FSV-BX 

FSV-CB 

FSV-CC 

FSV-CD 

FSV-CE 

FSV-CF 

FSV-CG 

FSV-CH 

FSV-CI 

FSV-CK 

FSV-CL 

FSV-CR 

Round Robin L Laboratory Results 

Comparability Summary 

TR tR RP aT g/bT bC tbC aC TLy tLy TbX TLu TZ L&Z 

1 1 1 1 1 1 1 1 2 1 1 1 

1 1 1 1 1 1 1 1 1 1 1 1 1 

1 2 

1 1 1 1 1 

1 1 1 2 1 1 1 

1 2 1 1 1 1 1 1 1 2 

2 1 1 2 3 1 1 3 1 1 1 

1 1 1 1 1 1 1 

1 1 1 1 1 1 1 1 1 1 1 

1 3 1 1 1 

1 2 

1 1 1 

1 1 2 2 1 1 1 2 2 1 

1 1 1 1 2 1 1 

1 1 1 1 1 1 

1 1 2 

1 1 1 1 1 

2 3 1 1 1 1 1 1 1 1 

1 1 1 1 1 1 2 1 

1 1 1 1 1 2 1 1 1 1 

1 1 1 1 1 1 1 3 1 3 

1 1 1 1 1 1 

1 2 1 

1 2 1 1 1 1 1 1 2 2 1 

2 2 1 

1 1 

1 2 1 1 2 1 1 1 1 1 

2 1 2 2 1 1 1 

2 1 2 1 1 

1 1 2 3 3 1 2 1 

4 4 2 2 1 1 1 1 1 1 

2 1 

Label 

Lab 

TR 

tR 

RP

aT 

g/bT

bC 

tbC 

aC 

TLy 

tLy 

TbX 

TLu 

TZ 

L&Z

n 

% 1 

% 2 

% 3 

% 4 

Definition 

 Participant code 

 Total Retinol 

 trans-Retinol 

 Retinyl palmitate 

α-Tocopherol 

 γ/β-Tocopherol 

 Total β-Carotene 

 trans-β-Carotene 

 Total α-Carotene 

 Total Lycopene 

 trans-Lycopene 

Total β-Cryptoxanthin 

 Total Lutein 

 Total Zeaxanthin 

 Total Lutein&Zeaxanthin 

 number of participants providing quantitative data 

 Percent of CS = 1 (within 1 SD of medians) 

 Percent of CS = 2 (within 2 SD of medians) 

 Percent of CS = 3 (within 3 SD of medians) 

 Percent of CS = 4 (3 or more SD from medians) 

“Comparability Score” 



















 

The Comparability Score (CS) summarizes your measurement 

performance for a given analyte relative to the consensus 

medians in this study. CS is the average distance (in units of 

standard deviation) of your measurement performance 

characteristics from the consensus performance. CS is 

calculated when the number of quantitative values you reported, 

Nyou, is at least two and at least six participants reported 

quantitative values for the analyte. 

We define CS as follows: 

MINIMUM 4,INTEGER 1 

i 





 





 

2 2 CS = + C + AP

i 

N 

i 

N

C = Concordance = 

you 

N 2

−Median 

NAU i 

1 

FSV-CV 4 2 2 1 2 4 3 

N − 

FSV-CW 2 1 2 1 1 1 1 1 1 1 

you

∑ 

= 









− ∑ 

= 

you You Median 

NAU i 1 i 

Youi 

i 1 

FSV-DQ 1 1 1 1 1 1 4 NAU = NIST Assigned Uncertainty 

FSV-DR 1 1 2 

For further details, please see FSV-DU 1 1 2 1 

FSV-CX 2 1 3 1 1 1 

FSV-CZ 1 4 2 

FSV-DB 1 2 2 1 1 1 1 1 

FSV-DD 2 

FSV-DF 1 

AP = Apparent Precision = FSV-DI 1 1 2 1 1 2 you 

Duewer DL, Kline MC, Sharpless KE, Brown Thomas J, Gary FSV-EH 2 1 2 2 2 2 1 1 1 1 1 KT. Micronutrients Measurement Quality Assurance 

FSV-EQ 1 1 1 1 2 1 1 

FSV-FB 1 2 2 1 1 1 3 1 2 1 2 

FSV-FJ 1 2 1 4 2 

NISTa 1 1 1 1 1 1 1 1 1 1 

NISTb 1 1 1 1 1 1 1 1 1 

n 41 10 12 47 27 33 14 29 27 11 27 16 15 24 

TR tR RP aT g/bT bC tbC aC TLy tLy TbX TLu TZ L&Z 

% 1 78 60 75 64 81 64 64 83 89 73 85 81 93 79 

% 2 17 40 25 28 19 30 21 10 7 18 11 13 7 13 

% 3 0 0 0 4 0 3 14 3 4 9 4 6 0 4 

% 4 5 0 0 4 0 3 0 3 0 0 0 0 0 4 

Program: Helping participants use interlaboratory comparison 

exercise results to improve their long-term measurement 

performance. Anal Chem 1999;71(9):1870-8. 

All Lab Report Page 6 / 6 

C7
 

Appendix D. Representative “Individualized Report” for RR15 

Each participant in RR15 received an “Individualized Report” reflecting their reported 

results. Each report included a detailed analysis for analytes that were assayed by at least 

five participants. The following analytes met this criterion in RR15: 

• Total Retinol 

• trans-Retinol 

• Retinyl Palmitate 

• α-Tocopherol 

• γ/β-Tocopherol 

• δ-Tocopherol 

• Total β-Carotene 

• trans-β-Carotene 

• Total cis-β-Carotene 

• Total α-Carotene 

• Total Lycopene 

• trans-Lycopene 

• Total β-Cryptoxanthin 

• Total α-Cryptoxanthin 

• Total Lutein 

• Total Zeaxanthin 

• Total Lutein & Zeaxanthin 

• Coenzyme Q10 

The following 12 pages are the “Individualized Report” for the analytes evaluated by 

participant FSV-BA. 

D1
 Set 1 of 49

Individualized Round Robin L Report: FSV-BA 

Summary 

Serum 274 Serum 275 Serum 276 Serum 277 

Analyte You NAV n You NAV n You NAV n You NAV n 

Total Retinol 0.654 0.646 39 0.452 0.456 39 0.608 0.610 40 0.431 0.443 40 

Retinyl Palmitate 0.01 0.02 11 0.1 0.1 12 0.0 0.0 10 0.06 0.05 12 

α-Tocopherol 6.38 6.05 44 6.84 6.98 45 5.94 5.81 45 6.53 6.55 45 

γ/β-Tocopherol 2.612 2.275 25 2.008 1.929 25 2.397 2.154 25 1.908 1.777 25 

Total β-Carotene 0.498 0.513 31 0.313 0.348 31 0.449 0.482 31 0.304 0.327 31 

trans-β-Carotene 0.476 0.508 12 0.294 0.329 13 0.425 0.464 13 0.286 0.296 13 

Total cis-β-Carotene 0.022 9 0.019 9 0.024 9 0.018 9 

Total α-Carotene 0.019 0.022 27 0.024 0.033 27 0.020 0.021 27 0.024 0.030 27 

trans-Lycopene 0.144 0.130 11 0.185 0.185 11 0.129 0.120 11 0.181 0.160 11 

Total β-Cryptoxanthin 0.078 0.045 25 0.076 0.053 25 0.069 0.048 25 0.081 0.049 25 

Total Lutein&Zeaxanthin 0.187 0.128 23 0.186 0.116 23 0.166 0.120 23 0.181 0.116 23 

D2

You : Your reported values for the listed analytes (micrograms/milliliter) 

NAV : NIST Assigned Values, equal to (NIST's average-of-averages + this RR's median) / 2 

n : Number of non-NIST laboratories reporting quantitative values for this analyte in this serum 

Please check our records against your records. Send corrections and/or updates to... 

Micronutrients Measurement Quality Assurance Program 

National Institute of Standards and Technology 

100 Bureau Drive Stop 8392 

Gaithersburg, MD 20899-8392 USA Email: d

 Individualized Report 
 

 

 

 Set 1 of 49

Individualized Round Robin L Report: FSV-BA 

Total Retinol 

Apparent Precision, SD 

[Analyte], μg/mL 

192199218250278267274270276271275266277 

Your [Analyte], μg/mL

Median [Analyte], μg/mL 

Apparent Precision, SD 

Long-term Precision, SD 

Median (50%) 

Concordance, SD 

3rd Quartile (75%) You, this RR You, >x, this RR NIST, this RR 

1st Quartile (25%) 

You, >x, past RRs You, past RRs Others, this RR 

For details of the construction and interpretation of these plots, see:
 

Duewer, Kline, Sharpless, Brown Thomas, Gary, Sowell. Anal Chem 1999;71(9):1870-8.
 

Serum History Comments 

#274 #267 RR48, same pool as #276 Fresh frozen 

#275 #271 RR49, same pool as #277 Fresh frozen 

#276 #270 RR49, same pool as #274 Lyophilized 

#277 #266 RR48, same pool as #275 Lyophilized 

#278 #192 RR30, #199 RR32, #218 RR36, #250 RR44 Lyophilized 

 Individualized Report Page 2 / 12 

D3
 

 

 

 Set 1 of 49

Individualized Round Robin L Report: FSV-BA 

Retinyl Palmitate 

Apparent Precision, SD 

[Analyte], μg/mL 

192199218250278267274270276271275266277 

Your [Analyte], μg/mL

Median [Analyte], μg/mL 

Apparent Precision, SD 

Long-term Precision, SD 

Median (50%) 

Concordance, SD 

3rd Quartile (75%) You, this RR You, >x, this RR NIST, this RR 

1st Quartile (25%) 

You, >x, past RRs You, past RRs Others, this RR 

For details of the construction and interpretation of these plots, see:
 

Duewer, Kline, Sharpless, Brown Thomas, Gary, Sowell. Anal Chem 1999;71(9):1870-8.
 

Serum History Comments 

#274 #267 RR48, same pool as #276 Fresh frozen 

#275 #271 RR49, same pool as #277 Fresh frozen 

#276 #270 RR49, same pool as #274 Lyophilized 

#277 #266 RR48, same pool as #275 Lyophilized 

#278 #192 RR30, #199 RR32, #218 RR36, #250 RR44 Lyophilized 

 Individualized Report Page 3 / 12 

D4
 

 

 

 Set 1 of 49

Individualized Round Robin L Report: FSV-BA 

α-Tocopherol 

Apparent Precision, SD 

[Analyte], μg/mL 

192199218250278267274270276271275266277

Your [Analyte], μg/mL

Median [Analyte], μg/mL 

Apparent Precision, SD 

Long-term Precision, SD 

Median (50%) 

Concordance, SD 

3rd Quartile (75%) You, this RR You, >x, this RR NIST, this RR 

1st Quartile (25%) 

You, >x, past RRs You, past RRs Others, this RR 

For details of the construction and interpretation of these plots, see:
 

Duewer, Kline, Sharpless, Brown Thomas, Gary, Sowell. Anal Chem 1999;71(9):1870-8.
 

Serum History Comments 

#274 #267 RR48, same pool as #276 Fresh frozen 

#275 #271 RR49, same pool as #277 Fresh frozen 

#276 #270 RR49, same pool as #274 Lyophilized 

#277 #266 RR48, same pool as #275 Lyophilized 

#278 #192 RR30, #199 RR32, #218 RR36, #250 RR44 Lyophilized 

 Individualized Report Page 4 / 12 

D5
 

 

 

 Set 1 of 49

Individualized Round Robin L Report: FSV-BA 

γ/β-Tocopherol 

Apparent Precision, SD 

[Analyte], μg/mL 

192199218250278267274270276271275266277

Your [Analyte], μg/mL

Median [Analyte], μg/mL 

Apparent Precision, SD 

Long-term Precision, SD 

Median (50%) 

Concordance, SD 

3rd Quartile (75%) You, this RR You, >x, this RR NIST, this RR 

1st Quartile (25%) 

You, >x, past RRs You, past RRs Others, this RR 

For details of the construction and interpretation of these plots, see:
 

Duewer, Kline, Sharpless, Brown Thomas, Gary, Sowell. Anal Chem 1999;71(9):1870-8.
 

Serum History Comments 

#274 #267 RR48, same pool as #276 Fresh frozen 

#275 #271 RR49, same pool as #277 Fresh frozen 

#276 #270 RR49, same pool as #274 Lyophilized 

#277 #266 RR48, same pool as #275 Lyophilized 

#278 #192 RR30, #199 RR32, #218 RR36, #250 RR44 Lyophilized 

 Individualized Report Page 5 / 12 

D6
 

 

 

 Set 1 of 49

Individualized Round Robin L Report: FSV-BA 

Total β-Carotene 

Apparent Precision, SD 

[Analyte], μg/mL 

192199218250278267274270276271275266277

Your [Analyte], μg/mL

Median [Analyte], μg/mL 

Apparent Precision, SD 

Long-term Precision, SD 

Median (50%) 

Concordance, SD 

3rd Quartile (75%) 

You, this RR You, >x, this RR NIST, this RR 

1st Quartile (25%) 

You, >x, past RRs You, past RRs Others, this RR 

For details of the construction and interpretation of these plots, see:
 

Duewer, Kline, Sharpless, Brown Thomas, Gary, Sowell. Anal Chem 1999;71(9):1870-8.
 

Serum History Comments 

#274 #267 RR48, same pool as #276 Fresh frozen 

#275 #271 RR49, same pool as #277 Fresh frozen 

#276 #270 RR49, same pool as #274 Lyophilized 

#277 #266 RR48, same pool as #275 Lyophilized 

#278 #192 RR30, #199 RR32, #218 RR36, #250 RR44 Lyophilized 

 Individualized Report Page 6 / 12 

D7
 

 

 

 Set 1 of 49

Individualized Round Robin L Report: FSV-BA 

trans-β-Carotene 

Apparent Precision, SD 

[Analyte], μg/mL 

192199218250278267274270276271275266277

Your [Analyte], μg/mL

Median [Analyte], μg/mL 

Apparent Precision, SD 

Long-term Precision, SD 

Median (50%) 

Concordance, SD 

3rd Quartile (75%) You, this RR You, >x, this RR NIST, this RR 

1st Quartile (25%) 

You, >x, past RRs You, past RRs Others, this RR 

For details of the construction and interpretation of these plots, see:
 

Duewer, Kline, Sharpless, Brown Thomas, Gary, Sowell. Anal Chem 1999;71(9):1870-8.
 

Serum History Comments 

#274 #267 RR48, same pool as #276 Fresh frozen 

#275 #271 RR49, same pool as #277 Fresh frozen 

#276 #270 RR49, same pool as #274 Lyophilized 

#277 #266 RR48, same pool as #275 Lyophilized 

#278 #192 RR30, #199 RR32, #218 RR36, #250 RR44 Lyophilized 

 Individualized Report Page 7 / 12 

D8
 

 

 

 Set 1 of 49

Individualized Round Robin L Report: FSV-BA 

Total α-Carotene 

Apparent Precision, SD 

[Analyte], μg/mL 

192199218250278267274270276271275266277

Your [Analyte], μg/mL

Median [Analyte], μg/mL 

Apparent Precision, SD 

Long-term Precision, SD 

Median (50%) 

Concordance, SD 

3rd Quartile (75%) You, this RR You, >x, this RR NIST, this RR 

1st Quartile (25%) 

You, >x, past RRs You, past RRs Others, this RR 

For details of the construction and interpretation of these plots, see:
 

Duewer, Kline, Sharpless, Brown Thomas, Gary, Sowell. Anal Chem 1999;71(9):1870-8.
 

Serum History Comments 

#274 #267 RR48, same pool as #276 Fresh frozen 

#275 #271 RR49, same pool as #277 Fresh frozen 

#276 #270 RR49, same pool as #274 Lyophilized 

#277 #266 RR48, same pool as #275 Lyophilized 

#278 #192 RR30, #199 RR32, #218 RR36, #250 RR44 Lyophilized 

 Individualized Report Page 8 / 12 

D9
 

 

 

 Set 1 of 49

Individualized Round Robin L Report: FSV-BA 

trans-Lycopene 

Apparent Precision, SD 

[Analyte], μg/mL 

192199218250278267274270276271275266277 

Your [Analyte], μg/mL

Median [Analyte], μg/mL 

Apparent Precision, SD 

Long-term Precision, SD 

Median (50%) 

Concordance, SD 

3rd Quartile (75%) You, this RR You, >x, this RR NIST, this RR 

1st Quartile (25%) 

You, >x, past RRs You, past RRs Others, this RR 

For details of the construction and interpretation of these plots, see:
 

Duewer, Kline, Sharpless, Brown Thomas, Gary, Sowell. Anal Chem 1999;71(9):1870-8.
 

Serum History Comments 

#274 #267 RR48, same pool as #276 Fresh frozen 

#275 #271 RR49, same pool as #277 Fresh frozen 

#276 #270 RR49, same pool as #274 Lyophilized 

#277 #266 RR48, same pool as #275 Lyophilized 

#278 #192 RR30, #199 RR32, #218 RR36, #250 RR44 Lyophilized 

 Individualized Report Page 9 / 12 

D10
 

 

 

 Set 1 of 49

Individualized Round Robin L Report: FSV-BA 

Total β-Cryptoxanthin 

Apparent Precision, SD 

[Analyte], μg/mL 

192199218250278267274270276271275266277

Your [Analyte], μg/mL

Median [Analyte], μg/mL 

Apparent Precision, SD 

Long-term Precision, SD 

Median (50%) 

Concordance, SD 

3rd Quartile (75%) You, this RR You, >x, this RR NIST, this RR 

1st Quartile (25%) 

You, >x, past RRs You, past RRs Others, this RR 

For details of the construction and interpretation of these plots, see:
 

Duewer, Kline, Sharpless, Brown Thomas, Gary, Sowell. Anal Chem 1999;71(9):1870-8.
 

Serum History Comments 

#274 #267 RR48, same pool as #276 Fresh frozen 

#275 #271 RR49, same pool as #277 Fresh frozen 

#276 #270 RR49, same pool as #274 Lyophilized 

#277 #266 RR48, same pool as #275 Lyophilized 

#278 #192 RR30, #199 RR32, #218 RR36, #250 RR44 Lyophilized 

 Individualized Report Page 10 / 12 

D11
 

 

 

 Set 1 of 49

Individualized Round Robin L Report: FSV-BA 

Total Lutein&Zeaxanthin 

Apparent Precision, SD 

[Analyte], μg/mL 

192199218250278267274270276271275266277

Your [Analyte], μg/mL

Median [Analyte], μg/mL 

Apparent Precision, SD 

Concordance, SD Long-term Precision, SD 

3rd Quartile (75%) You, this RR You, >x, this RR 

Median (50%) NIST, this RR 

1st Quartile (25%) 

You, >x, past RRs You, past RRs Others, this RR 

For details of the construction and interpretation of these plots, see:
 

Duewer, Kline, Sharpless, Brown Thomas, Gary, Sowell. Anal Chem 1999;71(9):1870-8.
 

Serum History Comments 

#274 #267 RR48, same pool as #276 Fresh frozen 

#275 #271 RR49, same pool as #277 Fresh frozen 

#276 #270 RR49, same pool as #274 Lyophilized 

#277 #266 RR48, same pool as #275 Lyophilized 

#278 #192 RR30, #199 RR32, #218 RR36, #250 RR44 Lyophilized 

 Individualized Report Page 11 / 12 

D12
Set 1 of 49 

Individualized Round Robin L Report: FSV-BA
 

Graphical Comparability Summary
 

Total Retinol α-Tocopherol Total β-Carotene 

D13

Retinyl Palmitate γ/β-Tocopherol trans-β-Carotene To

Total Lycopene δ-Tocopherol Total cis-β-Carotene Total L

trans-Lycopene Total β-Cryptoxanthin Total α-Carotene Co

Individualized Report 
 

 

Appendix E. Shipping Package Inserts for RR15 

The following five items were included in each package shipped to an RR15 participant: 

•	 Cover letter 

•	 Protocol for Preparation and Analysis of the Ascorbic Acid Solid Control
 

Material
 

•	 Preparation and Validation of Ascorbic Acid Solid Control Material Datasheet 

•	 Analysis of Control Materials and Test Samples Datasheet 

•	 Packing List and Shipment Receipt Confirmation Form 

The cover letter, preparation protocol, and the two datasheets were enclosed in a sealed 

waterproof bag along with the samples themselves. The packing list was placed at the 

top of the shipping box, between the cardboard covering and the foam insulation. 

E1
June 25, 2001 

Dear Colleague: 

UNITED STATES DEPARTMENT OF COMMERCE 

National Institute of Standards and Technology 

Gaithersburg, Maryland 20899· 

The enclosed group of samples constitutes Vitamin C Round Robin XV of the 2001 

Micronutrients Measurement Quality Assurance Program. Three vials of frozen serum (test 

samples) and a vial of solid ascorbic acid (control sample) are enclosed. Please follow the 

attached protocol when you analyze these samples. 

We recommend that you obtain Standard Reference Material (SRM) 970, Ascorbic Acid in 

Serum to validate your methodology and value assign in-house control materials. This SRM 

may be purchased from the Standard Materials Reference Program at NIST (Tel. (301) 975-6776, 

Fax (301) 948-3730, or e-mail: srmminfo@nist.gov. 

Return your results using the attached form by September 17, 2001. We also request that you 

send us a representative chromatogram from the analysis of each sample and indicate whether 

peak height or peak area was used in the calculation of the ascorbic acid concentration. Your 

results will be kept confidential. 

Please send your results to: 

Micronutrients Measurement Quality Assurance Program 

NIST 

100 Bureau Drive, Stop 8392 

Gaithersburg, MD 20899-8392 

If you have any questions or concerns please call me at (301) 975-3137, or contact me by Fax 

(301) 977-0685 or E-mail sam.margolis@nist.gov 

Thank you for your participation. We look forward to receiving your results. 

Sincerely, 

~~~ 

Sam A. Margolis, Ph.D. 

Research Chemist 

Analytical Chemistry Division 

Chemical Science and Technology Laboratory 

Enclosures 

NISI 

E2
 

 

 

 

 

 

 

Protocol for analyzing samples 

The control sample consists of a sample of solid ascorbic acid in an amber vial and should be used in 

the following manner (please record your mass on the attached report form): 

1.	 Prepare 250 mL of 5% metaphosphoric acid (MPA) in distilled water. 

2.	 Weigh 180-220 mg of the solid ascorbic acid sample to 0.1 mg (if possible), dissolve it in 

5% MPA in a 100 mL volumetric flask, and dilute to the 100 mL mark. Weigh the 

amount of MPA solution that was added. This will be referred to as the Stock 

Solution. 

3.	 Prepare three dilute solutions of the Stock Solution as follows: 

Dilute Solution 1: Weigh 0.500 mL of the stock solution into a 100 mL volumetric 

flask. Then dilute with 5% MPA solution to 100 mL mark and weigh the amount of 

MPA solution that was added. 

Dilute Solution 2: Weigh 0.250 mL of the stock solution into a 100 mL volumetric 

flask. Then dilute with 5% MPA solution to 100 mL mark and weigh the amount of 

MPA solution that was added. 

Dilute Solution 3: Weigh 0.125 mL of the stock solution into a 100 mL volumetric 

flask. Then dilute with 5% MPA solution to 100 mL mark and weigh the amount 

ofMPA solution that was added. 

4.	 Record the ultraviolet absorbance spectrum of Dilute Solution 1 against 5% MPA 

solution as the blank using paired cuvettes. Record the wavelength in the region of 240­

245 nm at which you observe the maximum absorbance and record the absorbance at that 

wavelength. 

5.	 Record the absorbance of the sample at 242, 243 and 244 nm. 

6.	 Measure the concentration of the ascorbic acid in all three dilute solutions and the 5% 

MPA diluent in duplicate along with the ampouled test samples using your usual 

methods. 

The purpose of measuring the absorbance at the wavelength maximum is to check the concentration 

of your sample. If your spectrophotometer is properly calibrated, the maximum absorbance should 

be between 243 and 244 nm. If the concentration is correct, the molar extinction coefficient (E1

%) of 

ascorbic acid at this wavelength (using a cell with a 1 cm path length) should be close to 550 ± 30 

nm. The extinction coefficient of your solution can be calculated using the following equation: 

E1% dl/g·cm = Observed Absorbanceλmax 

(g AA/100 mL stock)(g stock in 100 mL dilute solution)

 (g AA stock solution) + (g MPA solution in 100 mL dilute solution 1) 

E3
 

The test samples are in sealed ampoules and were prepared by adding equal volumes of 10% 

metaphosphoric acid to spiked human serum. We have checked the samples for stability and 

homogeneity. Only the total ascorbic acid is stable. While these samples contain some 

dehydroascorbic acid, its content is variable. Therefore, only total AA should be reported. The test 

samples sho_uld be defrosted by warming at 20 °C for not more than 10 min otherwise some 

irreversible degradation may occur. 

Each test sample should contain between 0 and 100 μmol of ascorbic acid/L of solution. The total 

ascorbic acid in each ampoule should be measured in duplicate by the method(s) used in your 

laboratory. Please report your results in μg/L of sample. 

E4
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

REPORT OF ANALYSIS
 

NAME: 

ADDRESS: 

Method of Analysis: 

Please note the type of method that you use. 

Please attach representative chromatograms. 

Method used for calculating ascorbic acid concentration. 

Was SRM 970 used to validate your method or value-assign your in-house controls? 

Peak height Peak area 

Manufacturer of ascorbic acid used to make in-house standards 

Were samples frozen upon receipt? Yes No 

Date of Analysis: 

PREPARATION OF STOCK SOLUTION AND DILUTED SOLUTION 

STOCK SOLUTION 

Mass of ascorbic acid in the Stock Solution mg 

Mass of 5% MPA added to the 100 mL volumetric flask g 

DILUTE SOLUTION 1 

Mass of added stock solution (0.5 mL) mg 

Mass of 5% MPA added to the 100 mL volumetric flask g 

Absorbance of Dilute Solution 1 at 242 nm AU 

Absorbance of Dilute Solution 1 at 243 nm AU 

Absorbance of Dilute Solution 1 at 244 nm AU 

Wavelength of maximum absorbance nm 

Calculated molar absorptivity dL/g·cm 

DILUTE SOLUTION 2 

Mass of added stock solution (0.250 mL) mg 

Mass of 5% MPA added to the 100 mL volumetric flask g 

DILUTE SOLUTION 3 

Mass of added stock solution (0.125 mL) mg 

Mass of 5% MPA added to the 100 mL volumetric flask g 

COMMENTS: (use other side if necessary) 

E5
 

REPORT OF ANALYSIS
 

RESULTS (μmol/L of Sample)
 

DILUTE SOLUTION 1 

REPLICATE 1 μmol/L of dilute solution 1 

REPLICATE 2 μmol/L of dilute solution 1 

DILUTE SOLUTION 2 

REPLICATE 1 μmol/L of dilute solution 2 

REPLICATE 2 μmol/L of dilute solution 2 

DILUTE SOLUTION 3 

REPLICATE 1 μmol/L of dilute solution 3 

REPLICATE 2 μmol/L of dilute solution 3 

5% MPA SOLUTION (DILUENT) 

REPLICATE 1 μmol/L of diluent 

REPLICATE 2 μmol/L of diluent 

TEST SAMPLE #1 

REPLICATE 1 μmol/L of Sample 1 

REPLICATE 2 μmol/L of Sample 1 

TEST SAMPLE #2 

REPLICATE 1 μmol/L of Sample 2 

REPLICATE 2 μmol/L of Sample 2 

TEST SAMPLE #3 

REPLICATE 1 μmol/L of Sample 3 

REPLICATE 2 μmol/L of Sample 3 

Return by September 17, 2001 to: Fax: 301-977-0685 Micronutrients 

Micronutrients Measurement Quality Assurance Program E-mail: sam.margolis@nist.gov 

NIST, 100 Bureau Drive, Stop 8392 

Gaithersburg, MD 20899-8392 

E6
 

 

 

 

Participant #: ________ Date: _____________ 

Vitamin C Round Robin 15
 

NIST Micronutrients Measurement Quality Assurance Program
 

Packing List and Shipment Receipt Confirmation Form
 

This box contains (we hope) one vial each of the following four VitC M2QAP samples: 

Sample Form 

#1 Liquid frozen (1:1 serum:10% MPA) 

#2 Liquid frozen (1:1 serum:10% MPA) 

#3 Liquid frozen (1:1 serum:10% MPA) 

Control Solid AA 

Please 1) Open the pack immediately 

2) Check that it contains one vial each of the above samples 

3) Check if samples #1, #2, and #3 arrived frozen 

4) Store the samples upright at -20  ̊C or below until analysis 

5) Complete the following information 

6) Fax the completed form to us at 301-977-0685 

(or email requested information to david.duewer@nist.gov) 

1) Date this shipment arrived: ___________________________ 

2) Are all four vials intact? Yes | No 

If "No", which one(s) were damaged? 

3) Was there any dry-ice left in cooler? Yes | No 

4) Did samples #1, #2, and #3 arrive frozen? Yes | No 

5) At what temperature are you storing the samples? _______  ̊C 

6) When do you anticipate analyzing these samples? ________________________ 

Your prompt return of this information will help control M2QAP expenses. 

The M2QAP Gang 

Mail: M2QAP 

NIST, Stop 8392 Fax: 301-977-0685 

Gaithersburg, MD 20899-8392 Email: David.Duewer@NIST.gov 

E7
 

 

Appendix F. Final Report for RR15 

The following three pages are the final report as provided to all participants: 

•	 Cover letter. 

•	 An information sheet that: 

o	 describes the contents of the “All-Lab” report, 

o	 describes the content of the “Individualized” report, 

o	 describes the nature of the test samples and details their previous distributions, 

if any, and 

o	 summarizes aspects of the study that we believe may be of interest to the 

participants. 

F1
January 10, 2002 

Dear Colleague: 

UNITED STATES DEPARTMENT OF COMMERCE 

National Institute of Standards and Technology 

Gaithersburg, Maryland 20899-

Enclosed is the summary report of the results for Round Robin 15 (RR15) for the measurement of 

total ascorbic acid (T AA, ascorbic acid plus dehydroascorbic acid) in human serum. Included in 

this report are: a summary of data for all laboratories and a summary of individual laboratory 

performance and interlaboratory accuracy and repeatability. As in previous reports, the estimated 

standard deviations (eSD) for the measurements are defined as 0.74 x interquartile range and the 

estimate coefficients of variation ( eCV) are defined as 100 x eSD/median. 

RR 15 consists of three unlmowns and one solid reference ascorbic acid for preparation of control 

solutions. Details regarding the samples can be found in the enclosed report. 

If you have concerns regarding your laboratory's performance, we suggest that you obtain and 

analyze a unit of Standard Reference Material (SRM) 970, Vitamin C in Frozen Human Serum. 

SRM 970 can be purchased from the NIST SRM Program at phone: 301-975-6776; fax: 301-

948-3730. If your measured values do not agree with the certified values, we suggest that you 

contact us for consultation. 

Also enclosed is a reprint of the newly released technical brief on the "Stability of Ascorbic Acid 

in Solutions Stored in Autosampler Vials" by S. A. Margolis and E. Park. If you have any 

questions regarding this report, please contact David Duewer at david.duewer@nist.gov, phone: 

301-975-3935 or Sam Margolis at sam.margolis@nist.gov, phone: 301-975-3137, fax: 301-977-

0685. 

ice Brown Thomas 

es arch Chemist 

lytical Chemistry Division 

Chemical Science and Technology Laboratory 

SamA~h.D. Research Chemist 

Analytical Chemistry Division 

Chemical Science and Technology Laboratory 

Enclosures 

Cc: S.A. Wise 

L.C. Sander 

F2

NlSI 
 

The NIST M2QAP Vitamin C Round Robin 15 (RR15) report consists of 

Page 

1 Summarizes your reported values for the nominal 55 mmol/L control solution and the SRM 

970 Level 1 and 2 samples distributed in RR11 through RR15. 

2 Graphical summary of your RR15 sample measurements. 

3 Graphical summary of your RR15 control solution measurements. 

Page “All Lab” Report 

1 A listing of the 

• Total Ascorbic Acid concentration [TAA] for the four control/calibration solutions, 

calculated from your reported gravimetric measurements 

• Measured [TAA] values and summary statistics for the control/calibration solutions 

• Calibration parameters - intercept, slope, r2, and mean square error (MSE) of calibration, 

calculated by regressing the gravimetric [TAA] vs the measured [TAA] 

• Density of the 5% (nominal) metaphosphoric acid (MPA) used to prepare the 

control/calibration solutions, calculated from your reported gravimetric measurements, 

and summary statistics 

• Wavelength of maximum absorption, maximum absorbance, and molar extinction 

coefficient (El%), calculated from your gravimetric and UV/vis spectrophotometric 

measurements, and summary statistics 

• Measured [TAA] values and summary statistics for the three 1:1 serum:MPA samples 

• [TAA] values and summary statistics for the three samples after correction to the 

calibration curve defined by the control/calibration solutions 

“Individualized” Report 

Samples. Three unknowns, one solid reference AA for control solutions. Sera samples 1 and 2 were 

prepared (05/98) as SRM 970, Level 1 and Level 2, respectively. Serum sample 3 was prepared 

(03/95) as sample 188b. Each serum sample was prepared by adding ascorbic acid to a serum pool 

that was depleted of ascorbic acid. 

Observations. 

1)	 Most of the molar extinction coefficients are within 2% of the literature value of 550 dL/gcm. (Most

were also correctly reported, despite our factor-of-I0 error in the equation--our apologies.) However,

there remain a few values outside this roughly limiting volumetric accuracy. Two of the relatively

high values are attributable to known weighing difficulties. Some of the remaining errors may be

attributable to the spectrophotometric measurements; given that there was some variability in the

location of the absorbance maximum, instrument calibration (both wavelength and absorbance

scales) and/or measurement practice (matching of sample and blank cuvettes?) could be an issue. 

2)	 Almost everyone prepared their MPA within about 10% of the nominal 5% weight/weight target

value. (One participant evidently prepared their control/calibration solutions in DI water.) We concur

with the participant who suggested that our instructions should specify preparation of at least 500 mL

of the 5% MPA. 

3)	 We have finally demonstrated that some of the reported sample differences can be attributed to

calibration inaccuracies. Regression of the calculated control/calibration solution [TAA] against the 

measured values enables "recalibration" of the reported sample [TAA] values against a common

standard. Nearly all of these corrected values are "better" (closer to the consensus median) than the 

F3
original measurements. The improvement for the 27 μmol/L sample S15:2 is fairly dramatic, from a

CV of 15% down to 5%. 

4)	 There is no sign of degradation (change in median [TAA] or increase in estimated standard 

deviation) in either SRM 970 Level 1 or Level 2 since their certification in 1998. We will continue to 

periodically monitor these materials. 

F4
Appendix G. “All-Lab Report” for RR15 

The following single page is the “All-Lab Report” as provided to all participants, with 

two exceptions: 

• the participant identifiers (Lab) have been altered. 

• the order in which the participant results are listed has been altered. 

The data summary in the “All-Lab Report” has been altered to ensure confidentiality of 

identification codes assigned to laboratories. 

G1
 

 

NIST Micronutrients Measurement Quality Assurance Program for Total Ascorbic A

"Round Robin" 15 - Sep 2001 

Control / Calibration Samples MPA Dilute Solution 1 

G2

Calibration Parameters Density Spectrophotometry Mea

Gravimetric, μmol/L Measured, μmol/L 

E1% Lab Date [Dil1] [Dil2] [Dil3] MPA Ctrl:1 Ctrl:2 Ctrl:3 Ctrl:4 Inter Slope R2 SEE g/mL S15:1 

λmax Amax 

VC-MA 18/09/01 55.8 27.8 13.6 0 57.9 28.9 14.2 0.0 0.04 1.04 1.000 0.0 1.033 243. 0.5465 556.5 8.8 

VC-MB 05/09/01 59.4 29.7 14.8 0 65.6 33.8 18.1 5.2 4.01 1.03 0.998 1.3 1.033 245. 0.5662 541.3 12.4 

VC-MC 12/07/01 56.3 27.1 14.4 0 54.5 26.6 13.7 0.0 -0.04 0.97 1.000 0.3 1.030 243. 0.539 543.4 7.8 

VC-ME 11/09/01 58.1 29.0 14.1 0 57.8 29.6 14.6 0.0 0.39 0.99 1.000 0.5 1.032 243. 0.5721 558.7 8.0 

VC-MG 05/09/01 56.7 28.9 15.0 0 57.5 29.0 13.7 0.0 -0.67 1.02 0.999 0.9 1.033 243.6 0.544 544.4 9.4 

VC-MH 12/07/01 55.2 27.5 13.5 0 53.3 26.9 13.0 0.0 0.01 0.97 1.000 0.2 1.032 244. 0.539 554.9 7.6 

VC-MI 03/08/01 61.6 30.7 14.9 0 51.9 23.6 9.5 0.0 -1.66 0.86 0.996 1.9 1.028 5.1 

VC-ML 06/09/01 55.9 27.9 14.0 0 46.4 23.3 12.6 0.0 0.41 0.82 0.999 0.6 1.034 243. 0.5905 599.6 8.2 

VC-MO 17/09/01 57.9 28.4 14.2 0 56.6 28.2 14.4 0.0 0.30 0.98 1.000 0.3 1.031 243. 0.563 552.5 9.3 

VC-MQ 12/07/01 0 55.5 28.3 14.4 0.0 243.6 0.592 572.0 6.4 

VC-MR 28/06/01 58.8 29.0 14.5 0 57.5 28.5 14.0 0.0 -0.06 0.98 1.000 0.2 1.031 244. 0.557 538.2 8.5 

VC-MS 11/07/01 56.9 28.5 14.6 0 58.3 29.5 15.3 0.0 0.17 1.02 1.000 0.2 1.032 243. 0.5389 537.3 10.6 

VC-NH 05/10/01 52.0 26.2 12.9 0 53.7 27.2 13.4 0.0 0.03 1.03 1.000 0.0 1.032 243. 0.5163 563.2 8.3 

VC-NI 10/09/01 55.3 27.6 13.8 0 50.9 26.5 12.4 0.0 0.05 0.93 0.999 0.7 1.027 243. 0.559 574.0 6.3 

VC-NK 14/09/01 57.8 28.7 14.4 0 67.6 41.4 32.4 15.3 16.94 0.88 0.992 2.4 1.000 243. 0.556 545.9 27.3 

NIST 14/09/01 61.9 30.3 15.0 0 59.1 29.9 14.9 0.0 0.41 0.95 1.000 0.6 1.032 243. 0.6011 550.9 10.1 

N 15 15 15 15 N 14 14 14 14 15 

Average 56.3 28.7 15.0 1.4 Average 1.029 243.4 0.5557 555.9 9.6 

SD 5.3 4.3 5.1 4.1 SD 0.009 0.6 0.0207 17.2 5.2 

Min 46.4 23.28 9.5 0.0 Min 1.000 243.0 0.5163 537.3 5.1 

%25 53.5 26.75 13.2 0.0 %25 1.031 243.0 0.5403 543.7 7.7 

Median 56.6 28.30 14.0 0.0 Median 1.032 243.0 0.5565 553.7 8.3 

%75 57.9 29.24 14.5 0.0 %75 1.033 243.6 0.5654 562.1 9.3 

Max 67.6 41.40 32.4 15.3 Max 1.034 245.0 0.5920 599.6 27.3 

eSD 3.1 1.98 0.9 0.0 eSD 0.002 0.0208 14.7 1.5 

CV 6 7 7 CV 0 4 3 19 

All Lab Report 
Appendix H. Representative “Individualized Report” for RR15 

Each participant in RR15 received an “Individualized Report” reflecting their reported 

results. The following three pages are the “Individualized Report” for participant 

“VC-MA”. 

H1
Set 1 of 16 

Vitamin C 'Round Robin' 15 Report: Participant VC-MA
 

Date Method RR Control 

09/23/98 HPLC-EC (Height) 11 55 mmol/L 

04/02/99 HPLC-EC (Height) 12 55 mmol/L 

09/17/01 HPLC-EC (Height) 13 55 mmol/L 

09/27/01 HPLC-EC (Height) 14 55 mmol/L, Crtl-1 

09/18/01 HPLC-EC (Height) 15 55 mmol/L, Crtl:1 

AA MPA Stock MPA 

mg g mg g Calc Obs 

[AA] mmol/L 

200.0 103.09 526.0 102.45 

215.0 103.10 517.1 102.52 

200.8 103.16 508.0 102.58 

200.3 103.23 510.0 102.31 

200.5 103.12 506.0 102.19 

57.8 6.1 

61.1 53.1 

0.0 55.9 

56.1 57.1 

55.8 57.9 

A242 A243 

OD OD 

0.0525 

0.0721 

0.5650 

0.5409 

0.5461 0.5465 

[TAA] mmol/Lsample 

RR Sample 

11 SRM Lv 1, A 

11 SRM Lv 1, B 

12 SRM Lv 1, A 

12 SRM Lv 1, B 

13 SRM Lv 1, S13:1 

14 SRM Lv 1, S14:3 

15 SRM Lv 1, S15:1 

H2

Rep1 Rep2 Factor Mean SDdup 

15.5 13.9 

14.0 14.5 

14.5 15.8 

16.1 15.1 

8.0 7.7 

8.9 8.7 

0.5 

0.5 

0.5 

0.5 

0.7 

1.0 

1.0 

7.4 0.6 

7.1 0.2 

7.6 0.5 

7.8 0.3 

8.4 8.5 

7.8 0.2 

8.8 0.1 

Mean SDrepeat 

8.0 3.2 

Grand Ave

11 SRM Lv 2, A 

11 SRM Lv 2, B 

12 SRM Lv 2, A 

12 SRM Lv 2, B 

13 SRM Lv 2, S13:2 

14 SRM Lv 2, S14:4 

15 SRM Lv 2, S15:2 

50.7 47.7 

48.8 54.0 

49.5 45.9 

46.2 47.9 

8.5 0.1 

25.7 26.4 

25.4 25.6 

0.5 

0.5 

0.5 

0.5 

0.7 

1.0 

1.0 

24.6 1.1 

25.7 1.8 

23.9 1.3 

23.5 0.6 

27.6 27.7 

26.0 0.5 

25.5 0.2 

25.6 10.5 

14 S14:2 (188B) 

15 S15:3 (188B) 

0.0 0.0 

0.0 0.0 

1.0 

1.0 

0.0 0.0 

0.0 0.0 

0.0 0.0 

Please check our records against your records. Send corrections and/or updates to... 

Micronutrients Measurement Quality Assurance Program 

National Institute of Standards and Technology 

100 Bureau Drive Stop 8392 

Gaithersburg, MD 20899-8392 USA 

Individualized Report 
 

 

 

Set 1 of 16 

Vitamin C 'Round Robin' 15 Report: Participant VC-MA 

Total Ascorbic Acid 

S14:2S15:3 S11:1S12:1S13:1S14:3S15:1S11:2S12:2S13:2S14:4S15:2 

[Total Ascorbic Acid], μmol/L 

Your [Total Ascorbic Acid], μmol/L

Median [Total Ascorbic Acid], μmol/L 

SRM 970 Lv 1 SRM 970 Lv 2 Apparent Precision, SD 

Concordance, SD 

3rd Quartile (75%) You, RR 15 NIST, RR 15 Median (50%) 

You, RR 11-14 Others, RR 11-14 

1st Quartile (25%) 

For details of the construction and interpretation of these plots, see: 

Duewer, Kline, Sharpless, Brown Thomas, Gary, Sowell. Anal Chem 1999;71(9):1870-8. 

Sample Comments 

S15:1 SRM 970 Level 1 

S15:2 SRM 970 Level 2 

S15:3 Serum 188B, no augmentation 

Individualized Report Page 2 / 3 

H3
 

 

 

Set 1 of 16 

Vitamin C 'Round Robin' 15 Report: Participant VC-MA 

Total Ascorbic Acid Adjusted to Gravimetrically Prepared Calibrants 

S14:2'S15:3' 

S11loS12lo

S13:1

S14:3'S15:1'

S11hiS12hi

S13:2

S14:4'S15:2' 

[Total Ascorbic Acid], μmol/L 

Your [Total Ascorbic Acid], μmol/L

Median [Total Ascorbic Acid], μmol/L 

SRM 970 Lv 1 SRM 970 Lv 2 Apparent Precision, SD 

Concordance, SD 

3rd Quartile (75%) You, RR 15 NIST, RR 15 Median (50%) 

You, RR 11-14 Others, RR 11-14 

1st Quartile (25%) 

For details of the construction and interpretation of these plots, see: 

Duewer, Kline, Sharpless, Brown Thomas, Gary, Sowell. Anal Chem 1999;71(9):1870-8. 

Sample Comments 

S15:1 SRM 970 Level 1 

S15:2 SRM 970 Level 2 

S15:3 Serum 188B, no augmentation 

Individualized Report Page 3 / 3 

H4