NISTIR 7880-15 

NIST Micronutrients Measurement 

Quality Assurance Program 

Winter 2005 

Comparability Studies 

Results for Round Robin LVII 

Fat-Soluble Vitamins and Carotenoids in Human Serum 

and Round Robin 22 Ascorbic Acid in Human Serum 

David L. Duewer 

Jeanice B. Thomas 

 

 

 

 

 

 

NISTIR 7880-15
 

NIST Micronutrients Measurement 

Quality Assurance Program 

Winter 2005 

Comparability Studies 

Results for Round Robin LVII 

Fat-Soluble Vitamins and Carotenoids in Human Serum 

and Round Robin 22 Ascorbic Acid in Human Serum 

David L. Duewer 

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) 

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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 

Winter 2005 MMQAP measurement comparability improvement studies: 1) Round Robin LVII FatSoluble Vitamins and Carotenoids in Human Serum and 2) Round Robin 22 Total Ascorbic Acid in 

Human Serum. The materials for both studies were shipped to participants in November 2004; 

participants were requested to provide their measurement results by March 2, 2005. 

Keywords 

Human Serum
	

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

Total Ascorbic Acid
	

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Table of Contents 

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

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

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

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

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

Round Robin 22: Vitamin C in Human Serum............................................................................... 2
	

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

Appendix A. Shipping Package Inserts for RR57........................................................................ A1
	

Appendix B. Final Report for RR57 .............................................................................................. B1 

Appendix C. “All-Lab Report” for RR57 ...................................................................................... C1
	

Appendix D. Representative “Individualized Report” for RR57 ............................................... D1
	

Appendix E. Shipping Package Inserts for RR22 ......................................................................... E1
	

Appendix F. Final Report for RR22............................................................................................... F1
	

Appendix G. “All-Lab Report” for RR22..................................................................................... G1
	

Appendix H. Representative “Individualized Report” for RR22............................................... H1
	

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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 LVII: Fat-Soluble Vitamins and Carotenoids in Human Serum 

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

LVII comparability study (hereafter referred to as RR57) received four lyophilized and one liquidfrozen 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 

November 2004. 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 RR57 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. 

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•	 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 22: Vitamin C in Human Serum 

Participants in the MMQAP Vitamin C in Human Serum Round Robin 22 comparability study 

(hereafter referred to as RR22) received four frozen serum test samples, two frozen control sera, 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 November 2004. The communication materials included in the sample shipment are 

provided in Appendix E. 

The test and control 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 RR22 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. 

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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. 

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Appendix A. Shipping Package Inserts for RR57 

The following three items were included in each package shipped to an RR57 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
November 8, 2004 

Dear Colleague: 

UNITED STATES DEPARTMENT OF COMMERCE 

Nat:ianal lnsMute at Standards and Technology 

Gaithersburg, Maryland 20899-CDJ1 

Enclosed are the samples (Sera 309 - 313) for the first fat-soluble vitamins and carotenoids in serum 

round 'robin study (Round Robin L viI) for the fiscal year (FY) OS NIST Micronutrients Measurement 

Quality Assurance Program. You will find one vial of each of one liquid-frozen and four lyophilized 

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 a value is obtained below your 

limit of quantification, please indicate this result on the form by using NQ (Not Quantified). Results are 

due to NIST by March 2, 2005. Results received more than two weeks after the due date will not be 

included in the summary report for this round robin study. The feedback report conceining the study will 

be provided in April. 

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

recommend that dissolution be facilitated with 3 to S 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 may 

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 retinol 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. Water should not be added to the liquid-frozen sample 313. 

For- consistency, we request that laboratories use the following absorptivities (E 1 % cm): retinol, 1843 at 

325 nm (ethanol); retinyl palmitate, 975 at 325 nm (ethanol); a-tocopherol, 75.8 at 292 nm (ethanol); ytocopherol, 91.4 at 298 nm (ethanol); a-carotene, 2800 at 444 nm (hexane); P-carotene, 2560 at 450 nm 

(ethanol), 2592 at 452 nm (hexane); lycopene, 3450 at 472 nm (hexane). 

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

Micronutrients Measurement Quality Assurance Program 

NIST 

100 Bureau Drive Stop 8392 

Gaithersburg, MD 20899-8392 

Fax: (301) 977-0685 

If you have questions or comments regarding this study, please call me at (301) 975-3120; e-mail me at 

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

. 

i Brown Thomas 

oh Chemist 

Analytical Chemistry Division 

Chemical Science and Technology Laboratory 

·Enclosures 

N•Si 

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Participant #: ________ Date: _____________ 

Round Robin LVII 

NIST Micronutrients Measurement Quality Assurance Program 

Analyte 309 310 311 312 313 Units* 

total retinol 

trans-retinol 

didehydroretinol 

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

 total Coenzyme Q10 

ubiquinol (QH2) 

ubiquinone (Qox) 

phylloquinone (K1) 

25-hydroxyvitamin D 

Other analytes? 

* we prefer μg/mL 

Was serum 309 frozen when received? Yes | No 

Comments: 

Mail: M2QAP 

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

Gaithersburg, MD 20899-8392 2-Mar-2005 Email: David.Duewer@NIST.gov 

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Participant #: ________ Date: _____________ 

Fat-Soluble Vitamins Round Robin LVII 

NIST Micronutrients Measurement Quality Assurance Program 

Packing List and Shipment Receipt Confirmation Form 

This box contains (we hope) one vial each of the following five FSV M2QAP sera: 

Serum Form Reconstitute? 

#309 Lyophilized Yes (1 ml H2O) 

#310 Lyophilized Yes (1 ml H2O) 

#311 Lyophilized Yes (1 ml H2O) 

#312 Lyophilized Yes (1 ml H2O) 

#313 Liquid frozen No 

Please 1) Open the pack immediately 

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

3) Check if serum 313 arrived frozen 

4) Store the samples 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 serum 313 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 is appreciated. 

The M2QAP Gang 

Mail: M2QAP 

NIST, Stop 8392 Fax: 301-977-0685 

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

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Appendix B. Final Report for RR57 

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
April 14, 2005 

Dear Colleague: 

UNITED STATES DEPARTMENT OF COMMERCE 

National Institute of Standards and Technology 

Gaithersburg, Maryland 20899-CXJ01 

Enclosed is the summary report of the results for round robin LVII (RR57) of the 2005 NIST 

Micronutrients Measurement Quality Assurance Program (M2

QAP) for the fat-soluble vitamins and 

carotenoids in human serum. Included in this report are: (1) a summary of data and measurement 

comparability scores for all laboratories, (2) a detailed graphical analysis of your results; and (3) a 

graphical summary of your measurement comparabilities relatiye to the NIST assigned values. 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 57 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 deviations 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. 

Samples for the second 2005 QA interlaboratory exercise will be shipped starting the week of May 16. 

We will send you a reminder via e-mail or fax a week prior to shipment. It is critical that you carefully 

inspect all samples upon arrival and that you promptly confirm to us that they have arrived. We will 

replace samples (lost or damaged in shipment or miss-packaged by us) only for participants who report 

the problem within one calendar week after the package arrives. 

If you have any questions regarding this report, please contact Dave Duewer at david.duewer@nist.gov 

or me atjbthomas@nist.gov, tel: 301/975-3120, or fax: 301/977-0685. 

~Sincerely, 

ce Brown Thomas 

earch Chemist 

Analytical Chemistry Division 

Chemical Science and Technology Laboratory 

Enclosures 

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6 

The NIST M2QAP Round Robin LVII (RR57) report consists of: 

Page “All Lab” Report
	

1-4
	 A listing of all results and statistics for analytes reported by at least two laboratories. 

5a A list of results for the analytes reported by only one laboratory. 

5b A legend for the above two lists. 

The text version of the “Comparability Summary” (or “Score Card”). 

Page “Individualized” Report 

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 8 other participants. 

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

Samples. The five sera below were distributed in RR57. 

Serum Description		 Prior Distributions 

309 Lyophilized blended serum with native carotenoid #249:RR44-9/98, #256:RR46-6/99, 

levels, augmented with α- and δ-tocopherol; SRM #264:RR48-3/01, #284:RR52-9/02, 

968c Level II. #299:RR55-3/04 

310 Lyophilized blend of the #311 augmented serum and #197:RR31-6/94, #211:RR35-9/95, 

stripped serum, in 1+3 ratio (i.e., measurand levels #245:RR43-6/98 

should be 1⁄4 those of #311). 

311 Lyophilized blended serum with native carotenoid #198:RR31-6/94, #212:RR35-9/95, 

levels, augmented with retinol, retinyl palmitate, and #246:RR43-6/98 

α- and γ-tocopherol. 

312 Lyophilized, native, single-donor, commercially #290:RR53-2/03, #300:RR55-3/04 

obtained serum prepared in 2002. The same 

material was used to prepare #313. 

313 Fresh-frozen, native, single-donor, commercially #292:RR53-2/03, #301:RR55-3/04 

obtained serum prepared in 2002. The same 

material was used to prepare #312. 

Results 

1)		 Sera Stability. There was no significant change in the median level or increase in the variability of 

any measurand in any of the sera. Note that Sera 310 and 311 were prepared more than 10 years ago. 

2)		 Relative Accuracy at Low Measurand Levels: Sera 310 and 311 were prepared to evaluate relative 

accuracy of measurements made at low measurand levels. The Serum 311 material was created by 

augmenting a blended serum pool having with fairly high native carotenoid levels with retinol, 

retinyl palmitate, α-tocopherol, and γ-tocopherol. The Serum #310 material was created by blending 

one part of the Serum 311 material with 3 parts stripped serum. The measurand levels in the 

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resulting Serum 310 pool should be ≈ 25% of those in the Serum 311 pool. The Table below reports 

the observed ratios for the measurands reported by at least 8 participants. Only the ratio for retinyl 

palmitate is significantly different from the expected 0.25 value in Serum 310; this could result from 

systematic underestimation of low retinyl palmitate levels or about half of the retinyl palmitate in 

Serum 310 has been lost since the materials were prepared or about half of the retinyl palmitate that 

should be in Serum 310 was lost during preparation. The ratio data from earlier comparisons of these 

materials agree well with the current values, suggesting that retinyl palmitate has not degraded during 

storage. However, we cannot yet distinguish between the other two possibilities. 

Ratio, Sera 310/311 

Measurand Mean -SD +SD 

Retinyl Palmitate 0.15 0.13 0.17 

trans-β-Carotene 0.21 0.19 0.24 

trans-Lycopene 0.21 0.20 0.23 

Total β-Carotene 0.22 0.18 0.27 

Total Lycopene 0.23 0.19 0.29 

Total α-Carotene 0.24 0.16 0.36 

α-Tocopherol 0.24 0.23 0.26 

Total Lutein&Zeaxanthin 0.25 0.21 0.29 

Total Retinol 0.25 0.23 0.27 

Total Lutein 0.26 0.21 0.32 

γ/β -Tocopherol 0.26 0.24 0.28 

Total β-Cryptoxanthin 0.28 0.22 0.38 

If your serum 310/311 ratio for any measurand is much different from 0.25, you should review the 

manner by which you integrate low-level signals. 

3)		 Matrix (Lyophilized vs. Fresh-Frozen) Differences. Sera 312 and 313 were prepared from the same 

serum pool. Since we suggest that you reconstitute our lyophilized samples with 1.0 mL water rather 

than to a total volume of 1.0 mL, the measurand levels in Serum 312 should be ≈ 95% of those in 

Serum 313. The observed average ratio ± SD over all measurands with 8 or more quantitative 

measurements is 0.952 ± 0.008. If any of your Sera 312/313 ratios are much different than 0.95, you 

should look at your measurement system for those measurands. If your lyophilized/fresh frozen 

ratios are consistently much different from 0.95, you should review how you reconstitute lyophilized 

materials. 

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Appendix C. “All-Lab Report” for RR57 

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 LVII Laboratory Results 

All Results in μg/mL 

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

Lab 309 310 311 312 313 

C2

FSV-BA 0.489 0.204 0.787 0.649 0.670 

FSV-BB 0.487 0.205 0.778 0.641 0.657 

FSV-BC 0.477 0.111 0.730 0.613 0.647 

FSV-BD 0.490 0.190 0.740 0.720 0.700 

FSV-BE 0.520 0.250 0.790 0.600 0.690 

FSV-BF 0.480 0.170 0.700 0.610 0.640 

FSV-BG 0.477 0.191 0.760 0.595 0.627 

FSV-BH 0.412 0.145 0.648 0.579 0.586 

FSV-BI 0.459 0.179 0.707 0.567 0.542 

FSV-BJ 0.480 0.188 0.724 0.551 0.596 

FSV-BK 0.509 0.190 0.784 0.643 0.679 

FSV-BL 0.490 0.110 0.460 0.690 0.720 

FSV-BM 0.486 0.180 0.752 0.623 0.646 

FSV-BN 0.456 0.190 0.693 0.545 0.601 

FSV-BO 0.470 - 0.705 0.690 0.667 

FSV-BP 0.482 - - 0.596 0.632 

FSV-BQ 0.580 0.183 0.908 0.708 0.731 

FSV-BR ≥0.510 ≥0.180 ≥0.730 ≥0.600 ≥0.660

FSV-BS 0.493 0.176 0.873 0.668 0.714 

FSV-BU 0.489 0.177 0.748 0.574 0.637 

FSV-BV 0.600 0.192 0.733 0.681 0.681 

FSV-BW 0.470 0.170 0.750 0.600 0.620 

FSV-BX ≥0.470 ≥0.183 ≥0.750 ≥0.596 ≥0.618

FSV-CC 0.510 0.200 0.770 0.600 0.620 

FSV-CD ≥0.496 ≥0.196 ≥0.813 ≥0.627 ≥0.657

FSV-CE 0.536 0.207 0.458 0.523 0.518 

FSV-CF 0.480 0.178 0.802 0.626 0.652 

FSV-CG 0.539 0.189 0.729 0.561 0.618 

FSV-CI 0.439 0.151 0.618 0.561 0.584 

FSV-CP 

FSV-CS 0.485 0.198 0.802 0.668 0.662 

FSV-CT 

FSV-CW 0.403 0.263 0.748 0.569 0.562 

FSV-CZ 0.490 0.210 0.790 0.630 0.650 

FSV-DA ≥0.471 ≥0.213 ≥0.758 ≥0.601 ≥0.633

FSV-DB 0.481 0.171 0.712 0.582 0.617 

FSV-DD 0.456 0.187 0.700 0.575 0.580 

FSV-DF 0.477 0.180 0.776 0.607 0.645 

FSV-DI 0.518 0.141 0.770 0.660 0.670 

FSV-DV 1.250 0.450 1.720 1.360 1.450 

FSV-DW 0.520 0.220 0.750 0.630 0.630 

FSV-ET 0.430 0.180 0.790 0.560 0.580 

309 310 311 312 313 

0.510 0.180 0.730 0.600 0.660 

0.470 0.183 0.750 0.596 0.618 

0.480 0.190 0.740 0.600 0.620 

0.496 0.196 0.813 0.627 0.657 

0.471 0.213 0.758 0.601 0.633 

309 310 311 312 313 

0.088 0.031 0.219 0.110 0.115 

0.069 0.017 0.225 0.066 0.073 

0.081 0.036 0.250 0.123 0.123 

0.097 0.048 0.296 0.107 0.103 

0.086 nq 0.278 0.094 0.095 

0.073 0.048 0.272 0.086 0.092 

0.110 0.050 0.340 0.120 0.130 

0.075 0.068 0.493 0.153 0.212 

0.077 0.033 0.254 0.091 0.099 

0.046 0.041 0.220 0.059 0.051 

0.070 0.048 

0.065 0.048 

0.291 0.084 0.086 

0.249 0.060 0.084 

309 310 311 312 313 

16.63 3.46 14.75 10.05 10.40 

17.11 3.52 14.99 10.09 10.33 

16.80 3.90 14.40 10.30 11.40 

18.10 4.00 14.90 10.20 10.80 

17.00 1.40 13.70 10.10 10.40 

16.41 3.42 14.28 9.64 10.09 

15.92 3.30 13.73 10.57 9.88 

18.32 3.73 15.34 10.73 10.23 

17.05 3.52 13.70 9.53 10.17 

16.96 3.03 13.91 9.42 9.96 

15.07 3.01 12.49 9.48 9.91 

16.40 3.60 15.20 10.30 10.90 

14.69 3.02 12.15 8.37 9.25 

15.69 4.05 13.70 9.48 9.86 

16.65 - - 10.70 9.57 

16.60 3.50 14.30 10.10 10.70 

14.84 3.10 14.35 9.92 10.93 

12.16 3.13 10.73 7.28 8.63 

16.02 3.84 13.94 9.97 10.44 

15.69 3.29 13.36 9.83 9.66 

15.55 3.74 13.48 9.12 10.00 

12.11 3.39 14.15 10.08 10.45 

18.82 4.01 16.50 10.55 11.28 

18.92 2.98 16.13 10.10 10.40 

18.46 3.26 10.94 6.55 9.87 

15.70 4.70 13.80 9.40 10.00 

14.65 2.37 12.20 7.93 8.96 

16.21 3.50 14.82 9.59 10.23 

16.71 5.89 14.51 10.49 10.41 

17.05 3.13 15.64 10.36 11.15 

18.60 3.80 15.20 10.20 11.60 

16.20 3.40 14.40 9.80 10.10 

17.63 3.80 14.72 10.46 11.02 

16.12 3.89 13.57 9.44 9.99 

17.30 3.68 14.60 10.50 11.20 

17.10 2.90 14.30 8.50 9.80 

16.65 3.31 13.71 10.17 10.45 

14.60 3.68 14.41 9.23 9.64 

309 310 311 31

1.589 0.706 2.693 1.8

1.537 0.687 2.512 1.7

1.700 0.900 2.800 1.8

1.700 0.300 2.600 1.8

1.561 0.678 2.575 1.7

1.449 0.639 2.461 1.6

1.750 0.660 2.830 1.8

1.527 0.718 2.429 1.6

1.289 0.587 2.013 1.2

1.029 0.504 1.668 1.1

1.548 0.719 2.432 1.7

1.570 0.670 2.540 1.7

1.617 0.633 2.637 1.7

1.905 0.859 3.288 1.9

1.544 0.634 2.523 1.6

1.430 0.660 2.470 1.5

1.910 0.740 2.980 2.4

1.553 0.707 3.318 2.6

1.700 0.700 2.600 1.8

1.550 0.704 2.690 1.8

1.536 0.574 2.392 1.7

1.480 0.620 2.510 1.6

1.240 0.570 2.570 1.5

N 36 34 35 36 36 5 5 5 5 5 12 11 12 12 12 38 37 37 38 38 23 23 23 

Min 0.403 0.110 0.458 0.523 0.518 0.470 0.180 0.730 0.596 0.618 0.046 0.017 0.219 0.059 0.051 12.11 1.40 10.73 6.55 8.63 1.029 0.300 1.668 1.1

Median 0.486 0.187 0.750 0.609 0.643 0.480 0.190 0.750 0.600 0.633 0.076 0.048 0.263 0.093 0.097 16.61 3.50 14.30 10.01 10.23 1.550 0.670 2.570 1.7

Max 1.250 0.450 1.720 1.360 1.450 0.510 0.213 0.813 0.627 0.660 0.110 0.068 0.493 0.153 0.212 18.92 5.89 16.50 10.73 11.60 1.910 0.900 3.318 2.6

SD 0.025 0.017 0.057 0.057 0.042 0.012 0.010 0.037 0.024 0.023 1.04 0.50 0.78 0.61 0.56 0.115 0.059 0.168 0.1

CV 5 9 8 9 7 0 0 0 0 0 16 21 14 26 24 6 14 5 6 5 7 9 7 

Npast 42 44 44 33 33 7 0 0 7 7 14 9 11 13 13 44 44 44 36 37 25 20 20 

Medianpast 0.482 0.196 0.730 0.601 0.638 0.480 0.605 0.648 0.081 0.052 0.277 0.095 0.103 16.61 3.59 14.20 9.85 10.47 1.579 0.701 2.610 1.7

SDpast 0.036 0.020 0.065 0.034 0.045 0.037 0.025 0.024 0.017 0.014 0.055 0.020 0.023 1.28 0.54 1.25 0.75 0.71 0.123 0.130 0.178 0.1

NIST 

NNIST 3 3 3 3 3 3 3 3 3 3 3 3 3 3 

Srep 0.009 0.008 0.029 0.019 0.017 0.006 0.08 0.11 0.14 0.01 0.38 0.019 0.004 0.092 0.0

Shet 0.005 0.004 0.008 0.016 0.005 0.007 0.26 0.04 0.18 0.21 0.10 0.012 0.012 0.047 0.0

SNIST 0.010 0.009 0.031 0.025 0.018 0.009 0.27 0.11 0.23 0.21 0.39 0.022 0.013 0.103 0.0

NAV 

0.497 ≥0.188 ≥0.789 ≥0.689 ≥0.673 0.489 0.188 0.789 0.689 0.673 16.76 3.49 14.54 10.95 10.47 1.549 0.695 2.570 1.7

0.491 0.188 0.769 0.650 0.658 0.484 0.190 0.750 0.600 0.633 0.076 0.048 0.263 0.093 0.097 16.69 3.49 14.42 10.51 10.37 1.550 0.684 2.571 1.7

NAU 0.040 0.016 0.065 0.080 0.055 0.039 0.016 0.059 0.048 0.050 0.021 0.016 0.060 0.025 0.026 1.29 0.42 1.11 1.00 0.81 0.171 0.090 0.255 0.1

All Lab Report 
Round Robin LVII Laboratory Results 

All Results in μg/mL 

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

Lab 309 310 311 312 313 

C3

FSV-BA 0.443 0.167 0.689 0.130 0.133 

FSV-BB 0.424 0.148 0.692 0.111 0.117 

FSV-BC 

FSV-BD 

FSV-BE 0.531 0.124 0.800 0.136 0.142 

FSV-BF 0.390 0.113 0.695 0.090 0.094 

FSV-BG 0.461 0.137 0.729 0.144 0.157 

FSV-BH 0.395 0.151 0.775 0.139 0.123 

FSV-BI 0.473 0.160 0.688 0.122 0.113 

FSV-BJ 0.491 0.133 0.788 0.124 0.119 

FSV-BK 

FSV-BL 

FSV-BM 

FSV-BN 0.401 0.139 0.606 0.103 0.114 

FSV-BO 0.456 0.130 0.723 0.110 0.117 

FSV-BP 0.444 - - 0.109 0.122 

FSV-BQ 

FSV-BR 

FSV-BS ≥0.414 ≥0.150 ≥0.633 ≥0.130 ≥0.144

FSV-BU 0.441 0.688 0.112 0.120 

FSV-BV 0.403 0.160 0.637 0.106 0.113 

FSV-BW 0.490 0.130 0.740 0.120 0.120 

FSV-BX ≥0.380 ≥0.134 ≥0.628 ≥0.115 ≥0.122

FSV-CC
 

FSV-CD
 0.436 0.103 0.583 0.081 0.107 

FSV-CE 0.496 0.132 0.547 0.049 0.123 

FSV-CF 

FSV-CG 0.369 0.111 0.569 0.097 0.111 

FSV-CI ≥0.367 ≥0.114 ≥0.582 ≥0.113 ≥0.123

FSV-CP 0.417 0.165 0.665 0.122 0.121 

FSV-CS 0.449 0.180 0.684 0.117 0.124 

FSV-CT 0.544 0.178 0.748 0.127 0.135 

FSV-CW 

FSV-CZ 0.440 0.170 0.560 0.130 0.160 

FSV-DA 0.440 0.157 0.724 0.130 0.140 

FSV-DB 0.377 0.131 0.620 0.106 0.114 

FSV-DD 

FSV-DF 

FSV-DI 0.417 0.150 0.680 0.065 0.075 

FSV-DV 

FSV-DW 0.260 0.140 0.380 0.060 0.050 

FSV-ET 0.380 0.140 0.690 0.110 0.120 

309 310 311 312 313 

0.414 0.155 0.643 0.123 0.127 

0.394 0.139 0.643 0.106 0.111 

0.369 0.138 0.718 0.139 0.123 

0.361 0.122 0.547 0.095 0.105 

0.414 0.150 0.633 0.130 0.144 

0.380 0.134 0.628 0.115 0.122 

0.339 0.099 0.519 0.091 0.104 

0.37 0.11 0.58 0.11 0.12 

0.375 0.183 0.718 0.116 0.122 

0.409 0.134 0.663 0.123 0.130 

309 310 311 312 313 

0.029 0.012 0.046 0.007 0.006 

0.030 0.009 0.048 0.005 0.006 

0.026 0.013 0.057 nq nq 

0.035 0.012 0.054 0.004 0.004 

0.030 0.012 0.050 0.006 0.008 

0.031 0.023 0.061 0.007 0.008 

309 310 311 312 313 

0.090 0.006 0.029 0.073 0.075 

0.090 0.008 0.035 0.064 0.068 

0.105 0.016 0.033 0.094 0.096 

0.096 0.014 0.038 0.080 0.084 

0.076 nq 0.040 0.071 0.069 

0.108 0.008 0.031 0.082 0.079 

0.118 nq 0.040 0.085 0.086 

0.095 0.002 0.031 0.073 0.080 

0.095 nq 0.038 0.070 0.074 

0.085 - - 0.065 0.079 

0.108 0.017 0.046 0.093 0.099 

0.099 0.035 0.075 0.080 

0.068 0.005 0.022 0.054 0.057 

0.150 nq 0.031 0.102 0.108 

0.093 0.007 0.032 0.085 0.087 

0.102 0.009 0.038 0.065 0.081 

0.106 0.008 0.040 0.075 0.086 

0.078 <0.016 0.031 0.061 0.067 

0.105 0.011 0.043 0.082 0.081 

0.106 0.010 0.037 0.079 0.083 

0.092 0.020 0.045 0.080 0.082 

0.100 0.008 0.040 0.079 0.085 

0.048 0.006 0.014 0.041 0.041 

309 

0.45

0.41

0.42

0.44

0.33

0.40

0.51

0.36

0.43

0.40

0.48

0.43

0.45

0.53

0.40

0.39

0.40

0.45

0.53

0.44

0.39

0.38

0.22

N 26 24 25 26 26 10 10 10 10 10 6 6 6 5 5 23 16 22 23 23 2

Min 0.260 0.103 0.380 0.049 0.050 0.339 0.099 0.519 0.091 0.104 0.026 0.009 0.046 0.004 0.004 0.048 0.002 0.014 0.041 0.041 0.22

Median 0.440 0.140 0.688 0.111 0.120 0.378 0.136 0.638 0.116 0.123 0.030 0.012 0.052 0.006 0.006 0.096 0.008 0.036 0.075 0.081 0.42

Max 0.544 0.180 0.800 0.144 0.160 0.414 0.183 0.718 0.139 0.144 0.035 0.023 0.061 0.007 0.008 0.150 0.020 0.046 0.102 0.108 0.53

SD 0.043 0.022 0.077 0.017 0.008 0.028 0.017 0.048 0.011 0.009 0.002 0.001 0.006 0.001 0.001 0.012 0.004 0.007 0.011 0.008 0.04

CV 10 16 11 15 7 7 12 7 10 7 5 5 11 19 25 12 45 19 14 10 1

Npast 30 32 32 26 26 14 10 10 13 13 10 8 8 7 7 26 22 26 23 23 2

Medianpast 0.424 0.154 0.678 0.112 0.120 0.386 0.152 0.634 0.108 0.115 0.030 0.016 0.052 0.007 0.007 0.096 0.009 0.034 0.071 0.076 0.41

SDpast 0.047 0.032 0.089 0.014 0.018 0.034 0.020 0.048 0.010 0.012 0.009 0.009 0.020 0.002 0.002 0.018 0.004 0.010 0.012 0.013 0.06

NIST 0.037 nq nq nq nq 0.431 ≥0.140 ≥0.669 ≥0.124 ≥0.125 0.394 0.140 0.669 0.124 0.125 0.100 nq nq 0.076 0.076
 

NNIST 3 3 3 3 3 3 3 3 3 3
 

Srep 0.007 0.002 0.017 0.004 0.001 0.016 0.011 0.003 0.002 0.003
 

Shet 0.006 0.001 0.021 0.002 0.001 0.010 0.010 0.006 0.002 0.001
 

SNIST 0.009 0.003 0.027 0.004 0.001 0.019 0.015 0.007 0.003 0.003
 

NAV 0.436 0.140 0.679 0.118 0.123 0.386 0.136 0.638 0.116 0.123 0.034 0.012 0.052 0.006 0.006 0.098 0.008 0.036 0.076 0.078 0.43

NAU 0.062 0.022 0.094 0.021 0.020 0.042 0.017 0.066 0.014 0.015 0.016 0.004 0.021 0.003 0.003 0.028 0.004 0.012 0.022 0.024 0.09

All Lab Report 
Round Robin LVII Laboratory Results 

All Results in μg/mL 

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

Lab 309 310 311 312 313 

C4

FSV-BA 0.215 0.016 0.068 0.277 0.290 

FSV-BB 0.184 0.011 0.057 0.229 0.240 

FSV-BC 

FSV-BD 

FSV-BE 

FSV-BF 

FSV-BG 0.229 0.017 0.078 0.300 0.307 

FSV-BH 

FSV-BI 

FSV-BJ 

FSV-BK 

FSV-BL 

FSV-BM 

FSV-BN 0.187 0.011 0.052 0.224 0.245 

FSV-BO 

FSV-BP 

FSV-BQ 

FSV-BR 

FSV-BS 

FSV-BU 

FSV-BV 

FSV-BW 

FSV-BX 0.179 0.014 0.065 0.244 0.253 

FSV-CC 

FSV-CD 

FSV-CE 

FSV-CF 

FSV-CG 0.194 0.011 0.061 0.221 0.255 

FSV-CI 

FSV-CP 

FSV-CS 

FSV-CT 

FSV-CW 0.211 0.022 0.080 0.289 0.306 

FSV-CZ 

FSV-DA 0.224 0.016 0.073 0.287 0.309 

FSV-DB 

FSV-DD 

FSV-DF 

FSV-DI 

FSV-DV 

FSV-DW 

FSV-ET 

309 310 311 312 313 

0.040 0.006 0.025 0.068 0.070 

0.030 0.005 0.019 0.051 0.053 

0.026 0.012 0.017 0.047 0.045 

0.030 0.006 0.020 0.054 0.057 

0.030 nq 0.021 0.058 0.058 

0.035 0.005 0.023 0.065 0.062 

0.032 nq 0.016 0.052 0.054 

0.021 nq 0.010 0.043 0.048 

0.023 nq 0.015 0.044 0.046 

0.014 - - 0.050 0.040 

0.048 0.008 0.019 0.073 0.060 

0.029 0.017 0.052 0.058 

0.023 0.003 0.013 0.043 0.045 

0.027 0.007 0.012 0.049 0.055 

0.028 0.006 0.018 0.049 0.051 

0.036 nq 0.014 0.056 0.062 

0.043 0.004 0.024 0.065 0.073 

0.039 0.007 0.023 0.065 0.066 

0.036 0.005 0.021 0.050 0.053 

0.039 0.007 0.018 0.050 0.056 

0.040 0.008 0.030 0.059 0.063 

0.044 0.007 0.025 0.064 0.067 

0.027 0.003 0.016 0.049 0.050 

0.026 0.006 0.016 0.044 0.046 

309 310 311 312 313 

0.022 nq 0.013 0.033 0.033 

0.014 0.002 0.007 0.022 0.023 

0.005 nq nq 0.017 0.016 

0.019 0.002 0.008 0.029 0.030 

309 310 311 312 313 

0.107 0.016 0.067 0.099 0.101 

0.097 0.013 0.057 0.078 0.072 

0.062 0.008 0.032 0.056 0.059 

0.086 0.013 0.049 0.075 0.072 

0.087 0.016 0.050 0.085 0.090 

0.062 0.015 0.039 0.055 0.062 

0.073 nq 0.050 0.071 0.073 

0.086 0.012 0.053 0.082 0.085 

0.061 0.013 0.040 0.064 0.067 

0.095 0.017 0.065 0.080 0.084 

0.115 nq 0.057 0.092 0.094 

0.085 0.015 0.061 0.087 0.084 

0.098 0.016 0.062 0.087 0.092 

0.072 0.012 0.046 0.064 0.068 

0.070 0.015 0.043 0.056 0.059 

309 

0.041 

0.023 

0.021 

0.036 

0.021 

0.011 

0.018 

0.018 

0.021 

0.024 

0.021 

0.028 

0.021 

N 8 8 8 8 8 24 17 23 24 24 4 2 3 4 4 15 13 15 15 15 13 

Min 0.179 0.011 0.052 0.221 0.240 0.014 0.003 0.010 0.043 0.040 0.005 0.002 0.007 0.017 0.016 0.061 0.008 0.032 0.055 0.059 0.011 

Median 0.203 0.015 0.067 0.260 0.273 0.030 0.006 0.018 0.052 0.055 0.016 0.002 0.008 0.026 0.027 0.086 0.015 0.050 0.078 0.073 0.021 

Max 0.229 0.022 0.080 0.300 0.309 0.048 0.012 0.030 0.073 0.073 0.022 0.002 0.013 0.033 0.033 0.115 0.017 0.067 0.099 0.101 0.041 

SD 0.023 0.004 0.010 0.044 0.041 0.009 0.001 0.004 0.008 0.009 0.006 0.007 0.007 0.018 0.002 0.011 0.016 0.015 0.003 

CV 11 26 16 17 15 30 24 24 16 16 35 27 27 21 15 22 21 21 12 

Npast 11 8 8 10 10 26 14 19 22 22 7 5 7 7 0 16 10 12 15 15 14 

Medianpast 0.208 0.021 0.077 0.248 0.268 0.032 0.007 0.022 0.051 0.053 0.017 0.005 0.012 0.021 0.085 0.014 0.053 0.078 0.083 0.024 

SDpast 0.036 0.008 0.020 0.042 0.053 0.008 0.003 0.007 0.007 0.010 0.006 0.002 0.014 0.004 0.011 0.017 0.016 0.007 

NIST 0.029 nq nq 0.050 0.049 0.085 nq 0.052 0.076 0.075 0.018 

NNIST 3 3 3 3 3 3 3 3 

Srep 0.003 0.002 0.002 0.003 0.002 0.002 0.003 0.003 

Shet 0.001 0.003 0.002 0.002 0.002 0.003 0.001 0.001 

SNIST 0.003 0.003 0.003 0.004 0.003 0.004 0.003 0.003 

NAV 0.203 0.015 0.067 0.260 0.273 0.030 0.006 0.019 0.051 0.053 0.016 0.008 0.026 0.027 0.085 0.015 0.051 0.077 0.074 0.019 

NAU 0.036 0.006 0.012 0.047 0.049 0.009 0.002 0.005 0.013 0.014 0.018 0.004 0.011 0.016 0.015 0.007 

All Lab Report 
Round Robin LVII Laboratory Results 

All Results in μg/mL 

Total Lutein&Zeaxanthin Coenzyme Q10 Ubiquinol Ubiquinone 

Lab 309 310 311 312 313 

C5

FSV-BA 0.107 0.022 0.072 0.111 0.115 

FSV-BB 0.148 0.021 0.092 0.152 0.156 

FSV-BC 

FSV-BD 

FSV-BE 

FSV-BF 0.111 0.013 0.068 0.109 0.112 

FSV-BG 0.109 0.016 0.069 0.091 0.086 

FSV-BH 0.083 0.008 0.044 0.083 0.089 

FSV-BI 0.122 0.020 0.072 0.116 0.111 

FSV-BJ 

FSV-BK 

FSV-BL 

FSV-BM 

FSV-BN 0.083 0.015 0.055 0.079 0.092 

FSV-BO 0.085 nq 0.0669 0.0940 0.0982 

FSV-BP 0.116 - - 0.099 0.115 

FSV-BQ 

FSV-BR 

FSV-BS 0.105 0.029 0.071 0.116 0.107 

FSV-BU 0.102 0.065 0.107 0.122 

FSV-BV 0.096 0.014 0.060 0.106 0.111 

FSV-BW 0.089 0.013 0.057 0.089 0.096 

FSV-BX 0.105 0.015 0.068 0.110 0.114 

FSV-CC 

FSV-CD 0.137 nq 0.074 0.118 0.110 

FSV-CE 

FSV-CF 

FSV-CG 0.125 0.019 0.078 0.126 0.141 

FSV-CI 0.079 <0.022 0.055 0.090 0.099 

FSV-CP 0.131 0.023 0.082 0.136 0.137 

FSV-CS 0.116 0.022 0.087 0.110 0.114 

FSV-CT 0.139 nq 0.063 0.125 0.128 

FSV-CW 0.106 0.024 0.080 0.114 0.111 

FSV-CZ 

FSV-DA 0.131 0.023 0.086 0.132 0.140 

FSV-DB 0.093 0.013 0.058 0.103 0.115 

FSV-DD 

FSV-DF 

FSV-DI 

FSV-DV 

FSV-DW 0.091 0.020 0.059 0.080 0.084 

FSV-ET 

309 310 311 312 313 

0.867 0.110 0.539 0.678 0.745 

0.980 0.100 0.520 0.670 0.690 

1.100 0.030 0.070 0.090 

0.690 <0.2 0.360 0.390 

0.916 0.045 0.660 0.808 

0.992 0.090 0.560 0.620 0.690 

0.090 

0.430 

0.836 

309 310 311 312 313 

0.780 0.053 0.400 0.500 0.350 

nd nd 0.208 0.138 0.234 

309 310 311 312 313 

0.150 0.047 0.120 0.170 0.340 

0.916 0.045 0.452 0.670 0.602 

N 24 18 23 24 24 6 5 6 6 6 1 1 2 2 2 2 2 2 2 2 

Min 0.079 0.008 0.044 0.079 0.084 0.690 0.030 0.070 0.090 0.090 0.208 0.138 0.234 0.150 0.045 0.120 0.170 0.340 

Median 0.107 0.020 0.068 0.109 0.112 0.948 0.090 0.530 0.645 0.690 0.780 0.053 0.304 0.319 0.292 0.533 0.046 0.286 0.420 0.471 

Max 0.148 0.029 0.092 0.152 0.156 1.100 0.110 0.660 0.808 0.836 0.400 0.500 0.350 0.916 0.047 0.452 0.670 0.602 

SD 0.022 0.006 0.012 0.017 0.013 0.081 0.041 0.115 0.170 0.175 

CV 21 29 18 16 12 9 46 22 26 25 

Npast 25 17 18 23 23 14 0 0 5 5 0 0 0 0 0 0 0 0 0 0 

Medianpast 0.109 0.021 0.074 0.107 0.112 0.950 0.739 0.810 

SDpast 0.023 0.010 0.013 0.018 0.019 0.081 0.035 0.047 

NIST 0.102 nq ≥0.052 0.104 0.099 

NNIST 3 3 3
 

Srep 0.003 0.005 0.002
 

Shet 0.002 0.005 0.002
 

SNIST 0.004 0.007 0.003
 

NAV 0.105 0.020 0.069 0.107 0.105 0.948 0.090 0.530 0.645 0.690 

NAU 0.023 0.005 0.014 0.023 0.025 0.081 0.041 0.115 0.170 0.175 

All Lab Report 
 

 

 

 

 

Round Robin LVII Laboratory Results
 

All Results in μg/mL
 

Analytes Reported By One Laboratory 

Term 

N 

Min 

Median 

Max 

SD 

CV 

Npast 

Medianpast 

SDpast 

NIST 

NNIST 

Srep 

Shet 

SNIST 

NAV 

NAU 

-

nd 

nq 

<x 

≥x

Analyte Code 309 310 311 312 313 

25-hydroxyvitamin D FSV-BN nq 0.0270 0.0170 0.0350 0.0230 

trans-Lutein FSV-DA 0.090 0.015 0.058 0.082 0.087 

Phytofluene FSV-DA 0.068 0.011 0.048 0.107 0.114 

Phytoene FSV-DA 0.051 0.009 0.052 0.125 0.132 

Retinyl stearate FSV-DA 0.030 0.005 0.037 0.033 0.034 

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 a NIST analyst

 Number of total vials analyzed in duplicate by NIST analysts

 W ithin-vial pooled standard deviation

 Among-vial pooled standard deviation 

2

)

0.5 Total standard deviation for NIST analyses: (Srep 2

 + Shet 

 NIST Assigned Value

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

 = Median 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 analyzed

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

 Detected but not quantitatively determined

 Concentration at or below the limit of quantification, x

 Concentration greater than or equal to x 

All Lab Report Page 5 / 6 

C6
 

 

 

 

 

 

 

 

Round Robin LVII Laboratory Results 

Comparability Summary 

Lab 

FSV-BA 

FSV-BB 

FSV-BC 

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-BS 

FSV-BU 

FSV-BV 

FSV-BW 

FSV-BX 

FSV-CC 

FSV-CD 

FSV-CE 

FSV-CF 

FSV-CG 

FSV-CI 

FSV-CP 

FSV-CS 

FSV-CT 

FSV-CW 

FSV-CZ 

FSV-DA 

FSV-DB 

FSV-DD 

FSV-DF 

FSV-DI 

FSV-DV 

FSV-DW 

FSV-ET 

NISTa 

n 

% 1 

% 2 

% 3 

% 4 

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

1 1 1 1 1 1 1 2 1 2 1 

1 1 1 1 1 1 1 1 1 1 1 

3 

1 1 1 

2 1 2 2 

1 3 3 2 2 1 2 1 

1 1 1 2 1 1 1 2 3 2 

2 1 1 1 1 1 1 1 

2 1 1 1 1 1 1 2 1 2 

1 1 1 1 1 1 1 1 1 1 

1 1 

4 2 1 

1 1 

1 2 2 1 2 1 1 2 1 

1 1 1 1 1 1 1 

1 1 1 1 1 2 2 1 2 

2 1 1 

1 1 2 2 1 

2 3 3 1 1 2 2 2 1 1 1 

1 1 1 1 1 1 1 

2 1 1 1 2 1 1 

1 1 1 2 1 1 1 

1 2 1 1 1 1 1 

1 2 1 

1 2 3 2 1 2 1 1 

3 3 2 1 

1 2 1 2 2 

1 2 1 2 2 1 1 2 1 

2 1 1 1 1 2 

3 4 1 1 1 1 1 

1 1 4 1 1 1 1 

2 1 1 1 1 1 

3 2 1 2 2 2 1 1 1 

1 1 2 

1 1 1 1 1 1 1 2 

1 1 1 1 1 1 1 1 1 

1 

1 1 

2 1 1 2 1 1 1 1 

4 2 

2 1 3 2 2 1 

1 1 2 1 

1 1 1 1 1 1 1 1 1 1 

41 39 24 30 11 24 23 25 16 14 25 

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

66 67 67 67 73 71 87 68 75 71 84 

22 23 13 30 27 29 13 32 25 21 16 

7 10 13 3 0 0 0 0 0 7 0 

5 0 8 0 0 0 0 0 0 0 0 

Label

Lab 

TR 

aT 

g/bT

bC 

tbC 

aC 

TLy 

TbX 

TLu 

TZ 

L&Z

n 

% 1 

% 2 

% 3 

% 4 

 Definition 

 Participant code 

 Total Retinol 

α-Tocopherol 

 γ/β-Tocopherol 

 Total β-Carotene 

 trans-β-Carotene 

 Total α-Carotene 

 Total 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) of summarizes your measurement 

performance for a given measurand, relative to the consensus 

medians. CS is the average distance, in standard deviation units, 

that your measurement performance characteristics are from the 

consensus performance. CS is calculated when the number of 

quantitative values you reported for a measurand, Nyou, is at least 

two and the measurand has been reported by 10 or more 

participants. 

CS = MIN(4, INT(1 + C2 + AP 2 )) 

N yo u You − Median C = Concordanc e = i i ∑ Ny ou NAU i i 

N you  You i − Median i 

2 

AP = Apparent Precision = ∑  (Ny ou − 1)   NAU i  i  

NAU = NIST Assigned Uncertainty, our estimate of the overall 

measurement standard deviation for each sample. The 

estimate includes serum heterogeneity, analytical 

repeatability, and among-participant reproducibility variance 

components. 

For further details, please see: Duewer DL, Kline MC, Sharpless 

KE, Brown Thomas J, Gary KT. Micronutrients Measurement 

Quality Assurance Program: Helping participants use 

interlaboratory comparison exercise results to improve their longterm measurement performance. Anal Chem 1999;71(9):1870-8. 

All Lab Report Page 6 / 6 

C7
 

 

 

 

Appendix D. Representative “Individualized Report” for RR57 

Each participant in RR57 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 RR57: 

• 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 Lutein 

• Total Zeaxanthin 

• Total Lutein & Zeaxanthin 

• Coenzyme Q10 

The following 15 pages are the “Individualized Report” for the analytes evaluated by 

participant FSV-BA. 

` 

D1
 

 Set 1 of 43 

Individualized Round Robin LVII Report: FSV-BA 

Summary 

Serum 309 Serum 310 Serum 311 Serum 312 

D2

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

Total Retinol 0.489 0.491 36 0.204 0.188 34 0.787 0.769 35 0.649 0.650 3

Retinyl Palmitate 0.09 0.08 12 0.0 0.0 11 0.2 0.3 12 0.11 0.09 1

α-Tocopherol 16.63 16.69 38 3.46 3.49 37 14.75 14.42 37 10.05 10.51 3

γ/β-Tocopherol 1.589 1.550 23 0.706 0.684 23 2.693 2.571 23 1.843 1.769 2

δ-Tocopherol 0.581 0.553 8 0.046 0.036 6 0.154 0.140 8 0.055 0.050 

Total β-Carotene 0.443 0.436 26 0.167 0.140 24 0.689 0.679 25 0.130 0.118 2

trans-β-Carotene 0.414 0.386 10 0.155 0.136 10 0.643 0.638 10 0.123 0.116 1

Total cis-β-Carotene 0.029 0.034 6 0.012 0.012 6 0.046 0.052 6 0.007 0.006 

Total α-Carotene 0.090 0.098 23 0.006 0.008 16 0.029 0.036 22 0.073 0.076 2

Total Lycopene 0.459 0.431 23 0.034 0.035 20 0.156 0.152 22 0.528 0.478 2

trans-Lycopene 0.215 0.203 8 0.016 0.015 8 0.068 0.067 8 0.277 0.260 

Total β-Cryptoxanthin 0.040 0.030 24 0.006 0.006 17 0.025 0.019 23 0.068 0.051 2

Total α-Cryptoxanthin 0.022 0.016 4 nq 2 0.013 0.008 3 0.033 0.026 

Total Lutein&Zeaxanthin 0.107 0.105 24 0.02 0.02 18 0.07 0.07 23 0.111 0.107 2

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

NAV : NIST Assigned Values, here equal to this RR's median 

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

nq : Detected, but not quantitatively determined 

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 Emai

Individualized Report 
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.

 

 Set 1 of 43

Individualized RR LVII Report: FSV-BA 

Total Retinol 

Apparent Precision, SD [Analyte], μg/mL

249256264284299309197211245310198212246311290300312292301313 

Your [Analyte], μg/mL

Median [Analyte], μg/mL 

Apparent Precision, SD 

Long-term Precision, SD Concordance, SD 

3rd Quartile (75%) 

You, this RR You, ≥x, this RR NIST, this RR 

Median (50%) 

You, past RRs You, ≥x, past RRs Others, this RR 1st Quartile (25%) 

Serum History Comments 

#309 Lyophilized - 44:249, 46:256, 48:264, 52:284, 55:299 Augmented, multi-source (SRM 968c Level II) 

#310 Lyophilized - 31:197, 35:211, 43:245 Same as #311, 1:3 diluted with stripped serum 

#311 Lyophilized - 31:198, 35:212, 43:246 Augmented, multi-source 

#312 Lyophilized - 53:290, 55:300 Native, single-source 

#313 Fresh-frozen: 53:292, 55:301 Native, single-source, hemolyzed 

 Individualized Report Page 2 / 15 

D3
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.

 

 Set 1 of 43

Individualized RR LVII Report: FSV-BA 

Retinyl Palmitate 

Apparent Precision, SD [Analyte], μg/mL

249256264284299309197211245310198212246311290300312292301313 

Your [Analyte], μg/mL

Median [Analyte], μg/mL 

Apparent Precision, SD 

Long-term Precision, SD Concordance, SD 

3rd Quartile (75%) 

You, this RR You, ≥x, this RR NIST, this RR 

Median (50%) 

You, past RRs You, ≥x, past RRs Others, this RR 1st Quartile (25%) 

Serum History Comments 

#309 Lyophilized - 44:249, 46:256, 48:264, 52:284, 55:299 Augmented, multi-source (SRM 968c Level II) 

#310 Lyophilized - 31:197, 35:211, 43:245 Same as #311, 1:3 diluted with stripped serum 

#311 Lyophilized - 31:198, 35:212, 43:246 Augmented, multi-source 

#312 Lyophilized - 53:290, 55:300 Native, single-source 

#313 Fresh-frozen: 53:292, 55:301 Native, single-source, hemolyzed 

 Individualized Report Page 3 / 15 

D4
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.

 

 Set 1 of 43

Individualized RR LVII Report: FSV-BA 

α-Tocopherol 

Apparent Precision, SD [Analyte], μg/mL

249256264284299309197211245310198212246311290300312292301313 

Your [Analyte], μg/mL

Median [Analyte], μg/mL 

Apparent Precision, SD 

Long-term Precision, SD Concordance, SD 

3rd Quartile (75%) 

You, this RR You, ≥x, this RR NIST, this RR 

Median (50%) 

You, past RRs You, ≥x, past RRs Others, this RR 1st Quartile (25%) 

Serum History Comments 

#309 Lyophilized - 44:249, 46:256, 48:264, 52:284, 55:299 Augmented, multi-source (SRM 968c Level II) 

#310 Lyophilized - 31:197, 35:211, 43:245 Same as #311, 1:3 diluted with stripped serum 

#311 Lyophilized - 31:198, 35:212, 43:246 Augmented, multi-source 

#312 Lyophilized - 53:290, 55:300 Native, single-source 

#313 Fresh-frozen: 53:292, 55:301 Native, single-source, hemolyzed 

 Individualized Report Page 4 / 15 

D5
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.

 

 Set 1 of 43

Individualized RR LVII Report: FSV-BA 

γ/β-Tocopherol 

Apparent Precision, SD [Analyte], μg/mL

249256264284299309197211245310198212246311290300312292301313 

Your [Analyte], μg/mL

Median [Analyte], μg/mL 

Apparent Precision, SD 

Long-term Precision, SD Concordance, SD 

3rd Quartile (75%) 

You, this RR You, ≥x, this RR NIST, this RR 

Median (50%) 

You, past RRs You, ≥x, past RRs Others, this RR 1st Quartile (25%) 

Serum History Comments 

#309 Lyophilized - 44:249, 46:256, 48:264, 52:284, 55:299 Augmented, multi-source (SRM 968c Level II) 

#310 Lyophilized - 31:197, 35:211, 43:245 Same as #311, 1:3 diluted with stripped serum 

#311 Lyophilized - 31:198, 35:212, 43:246 Augmented, multi-source 

#312 Lyophilized - 53:290, 55:300 Native, single-source 

#313 Fresh-frozen: 53:292, 55:301 Native, single-source, hemolyzed 

 Individualized Report Page 5 / 15 

D6
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.

 

 Set 1 of 43

Individualized RR LVII Report: FSV-BA 

δ-Tocopherol 

Apparent Precision, SD [Analyte], μg/mL

Your [Analyte], μg/mL

249256264284299309197211245310198212246311290300312292301313

Median [Analyte], μg/mL 

Apparent Precision, SD 

Long-term Precision, SD Concordance, SD 

3rd Quartile (75%) 

You, this RR You, ≥x, this RR NIST, this RR 

Median (50%) 

You, past RRs You, ≥x, past RRs Others, this RR 1st Quartile (25%) 

Serum History Comments 

#309 Lyophilized - 44:249, 46:256, 48:264, 52:284, 55:299 Augmented, multi-source (SRM 968c Level II) 

#310 Lyophilized - 31:197, 35:211, 43:245 Same as #311, 1:3 diluted with stripped serum 

#311 Lyophilized - 31:198, 35:212, 43:246 Augmented, multi-source 

#312 Lyophilized - 53:290, 55:300 Native, single-source 

#313 Fresh-frozen: 53:292, 55:301 Native, single-source, hemolyzed 

 Individualized Report Page 6 / 15 

D7
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.

 

 Set 1 of 43

Individualized RR LVII Report: FSV-BA 

Total β-Carotene 

Apparent Precision, SD [Analyte], μg/mL

249256264284299309197211245310198212246311290300312292301313 

Your [Analyte], μg/mL

Median [Analyte], μg/mL 

Apparent Precision, SD 

Long-term Precision, SD Concordance, SD 

3rd Quartile (75%) 

You, this RR You, ≥x, this RR NIST, this RR 

Median (50%) 

You, past RRs You, ≥x, past RRs Others, this RR 1st Quartile (25%) 

Serum History Comments 

#309 Lyophilized - 44:249, 46:256, 48:264, 52:284, 55:299 Augmented, multi-source (SRM 968c Level II) 

#310 Lyophilized - 31:197, 35:211, 43:245 Same as #311, 1:3 diluted with stripped serum 

#311 Lyophilized - 31:198, 35:212, 43:246 Augmented, multi-source 

#312 Lyophilized - 53:290, 55:300 Native, single-source 

#313 Fresh-frozen: 53:292, 55:301 Native, single-source, hemolyzed 

 Individualized Report Page 7 / 15 

D8
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.

 

 Set 1 of 43

Individualized RR LVII Report: FSV-BA 

trans-β-Carotene 

Apparent Precision, SD [Analyte], μg/mL

249256264284299309197211245310198212246311290300312292301313 

Your [Analyte], μg/mL

Median [Analyte], μg/mL 

Apparent Precision, SD 

Long-term Precision, SD Concordance, SD 

3rd Quartile (75%) 

You, this RR You, ≥x, this RR NIST, this RR 

Median (50%) 

You, past RRs You, ≥x, past RRs Others, this RR 1st Quartile (25%) 

Serum History Comments 

#309 Lyophilized - 44:249, 46:256, 48:264, 52:284, 55:299 Augmented, multi-source (SRM 968c Level II) 

#310 Lyophilized - 31:197, 35:211, 43:245 Same as #311, 1:3 diluted with stripped serum 

#311 Lyophilized - 31:198, 35:212, 43:246 Augmented, multi-source 

#312 Lyophilized - 53:290, 55:300 Native, single-source 

#313 Fresh-frozen: 53:292, 55:301 Native, single-source, hemolyzed 

 Individualized Report Page 8 / 15 

D9
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.

 

 Set 1 of 43

Individualized RR LVII Report: FSV-BA 

Total cis-β-Carotene 

Apparent Precision, SD [Analyte], μg/mL

Your [Analyte], μg/mL

249256264284299309197211245310198212246311290300312292301313

Median [Analyte], μg/mL 

Apparent Precision, SD 

Long-term Precision, SD Concordance, SD 

3rd Quartile (75%) 

You, this RR You, ≥x, this RR NIST, this RR 

Median (50%) 

You, past RRs You, ≥x, past RRs Others, this RR 1st Quartile (25%) 

Serum History Comments 

#309 Lyophilized - 44:249, 46:256, 48:264, 52:284, 55:299 Augmented, multi-source (SRM 968c Level II) 

#310 Lyophilized - 31:197, 35:211, 43:245 Same as #311, 1:3 diluted with stripped serum 

#311 Lyophilized - 31:198, 35:212, 43:246 Augmented, multi-source 

#312 Lyophilized - 53:290, 55:300 Native, single-source 

#313 Fresh-frozen: 53:292, 55:301 Native, single-source, hemolyzed 

 Individualized Report Page 9 / 15 

D10
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.

 

 Set 1 of 43

Individualized RR LVII Report: FSV-BA 

Total α-Carotene 

Apparent Precision, SD [Analyte], μg/mL

249256264284299309197211245310198212246311290300312292301313 

Your [Analyte], μg/mL

Median [Analyte], μg/mL 

Apparent Precision, SD 

Long-term Precision, SD Concordance, SD 

3rd Quartile (75%) 

You, this RR You, ≥x, this RR NIST, this RR 

Median (50%) 

You, past RRs You, ≥x, past RRs Others, this RR 1st Quartile (25%) 

Serum History Comments 

#309 Lyophilized - 44:249, 46:256, 48:264, 52:284, 55:299 Augmented, multi-source (SRM 968c Level II) 

#310 Lyophilized - 31:197, 35:211, 43:245 Same as #311, 1:3 diluted with stripped serum 

#311 Lyophilized - 31:198, 35:212, 43:246 Augmented, multi-source 

#312 Lyophilized - 53:290, 55:300 Native, single-source 

#313 Fresh-frozen: 53:292, 55:301 Native, single-source, hemolyzed 

 Individualized Report Page 10 / 15 

D11
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.

 

 Set 1 of 43

Individualized RR LVII Report: FSV-BA 

Total Lycopene 

Apparent Precision, SD [Analyte], μg/mL

Your [Analyte], μg/mL

249256264284299309197211245310198212246311290300312292301313

Median [Analyte], μg/mL 

Apparent Precision, SD 

Long-term Precision, SD Concordance, SD 

3rd Quartile (75%) 

You, this RR You, ≥x, this RR NIST, this RR 

Median (50%) 

You, past RRs You, ≥x, past RRs Others, this RR 1st Quartile (25%) 

Serum History Comments 

#309 Lyophilized - 44:249, 46:256, 48:264, 52:284, 55:299 Augmented, multi-source (SRM 968c Level II) 

#310 Lyophilized - 31:197, 35:211, 43:245 Same as #311, 1:3 diluted with stripped serum 

#311 Lyophilized - 31:198, 35:212, 43:246 Augmented, multi-source 

#312 Lyophilized - 53:290, 55:300 Native, single-source 

#313 Fresh-frozen: 53:292, 55:301 Native, single-source, hemolyzed 

 Individualized Report Page 11 / 15 

D12
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.

 

 Set 1 of 43

Individualized RR LVII Report: FSV-BA 

trans-Lycopene 

Apparent Precision, SD [Analyte], μg/mL

249256264284299309197211245310198212246311290300312292301313 

Your [Analyte], μg/mL

Median [Analyte], μg/mL 

Apparent Precision, SD 

Long-term Precision, SD Concordance, SD 

3rd Quartile (75%) 

You, this RR You, ≥x, this RR NIST, this RR 

Median (50%) 

You, past RRs You, ≥x, past RRs Others, this RR 1st Quartile (25%) 

Serum History Comments 

#309 Lyophilized - 44:249, 46:256, 48:264, 52:284, 55:299 Augmented, multi-source (SRM 968c Level II) 

#310 Lyophilized - 31:197, 35:211, 43:245 Same as #311, 1:3 diluted with stripped serum 

#311 Lyophilized - 31:198, 35:212, 43:246 Augmented, multi-source 

#312 Lyophilized - 53:290, 55:300 Native, single-source 

#313 Fresh-frozen: 53:292, 55:301 Native, single-source, hemolyzed 

 Individualized Report Page 12 / 15 

D13
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.

 

 Set 1 of 43

Individualized RR LVII Report: FSV-BA 

Total β-Cryptoxanthin 

Apparent Precision, SD [Analyte], μg/mL

249256264284299309197211245310198212246311290300312292301313 

Your [Analyte], μg/mL

Median [Analyte], μg/mL 

Apparent Precision, SD 

Long-term Precision, SD Concordance, SD 

3rd Quartile (75%) 

You, this RR You, ≥x, this RR NIST, this RR 

Median (50%) 

You, past RRs You, ≥x, past RRs Others, this RR 1st Quartile (25%) 

Serum History Comments 

#309 Lyophilized - 44:249, 46:256, 48:264, 52:284, 55:299 Augmented, multi-source (SRM 968c Level II) 

#310 Lyophilized - 31:197, 35:211, 43:245 Same as #311, 1:3 diluted with stripped serum 

#311 Lyophilized - 31:198, 35:212, 43:246 Augmented, multi-source 

#312 Lyophilized - 53:290, 55:300 Native, single-source 

#313 Fresh-frozen: 53:292, 55:301 Native, single-source, hemolyzed 

 Individualized Report Page 13 / 15 

D14
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.

 

 Set 1 of 43

Individualized RR LVII Report: FSV-BA 

Total Lutein&Zeaxanthin 

Apparent Precision, SD [Analyte], μg/mL

249256264284299309197211245310198212246311290300312292301313 

Your [Analyte], μg/mL

Median [Analyte], μg/mL 

Apparent Precision, SD 

Long-term Precision, SD Concordance, SD 

3rd Quartile (75%) 

You, this RR You, ≥x, this RR NIST, this RR 

Median (50%) 

You, past RRs You, ≥x, past RRs Others, this RR 1st Quartile (25%) 

Serum History Comments 

#309 Lyophilized - 44:249, 46:256, 48:264, 52:284, 55:299 Augmented, multi-source (SRM 968c Level II) 

#310 Lyophilized - 31:197, 35:211, 43:245 Same as #311, 1:3 diluted with stripped serum 

#311 Lyophilized - 31:198, 35:212, 43:246 Augmented, multi-source 

#312 Lyophilized - 53:290, 55:300 Native, single-source 

#313 Fresh-frozen: 53:292, 55:301 Native, single-source, hemolyzed 

 Individualized Report Page 14 / 15 

D15
Set 1 of 43 

Individualized Round Robin LVII Report: FSV-BA
 

Graphical Comparability Summary
 

Total Retinol α-Tocopherol Total β-Carotene 

D16

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 RR22 

The following five items were included in each package shipped to an RR22 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
November 8, 2004 

UNITED STATES DEPARTMENT OF COMMERCE 

National Institute of Standard& and Technology 

Gaithersburg, Maryland 20899-CXJ01 

Dear Colleague: 

The samples within this package constitute Vitamin C Round Robin 22 (RR22) of the 2005 Micronutrients 

Measurement Quality Assurance Program. 

RR22 consists of four vials of frozen serum test samples (#23, #33, #42, and #70), one vial of ascorbic acid 

solid control material (Control), and two vials of frozen serum control materials (Control #1 and Control #2). 

Please follow the attached protocols when you prepare and analyze these samples. If you cannot prepare the 

solid control solutions gravimetrically, please prepare equivalent solutions volumetrically and report the exact 

volumes used. (Routine 0.5 g gravime.tric measurements are generally 10-fold more accurate than routine 0.5 

mL volumetric measurements.) 

The two serum control materials are a new component of the M2

QAP for Vitamin C. Please use these 

materials to validate the performance of your measurement system before you analyze the test samples. The 

target value and :::::95% confidence interval for Control #1 is 8.41 ±0.61 μmol/L sample; the target value and 

:::::95% confidence interval for Control #2 is 28.05 ±0.49 μmol/L sample. 

Please be aware that sample contact with any oxidant-contaminated surface (vials, glassware, etc.) may degrade 

your measurement system's performance (SA Margolis and E Park, "Stability of Asc~rbic Acid in Solutions in 

Autosampler Vials", Clinical Chemistry 2001, 47(8), 1463-1464). You should suspect such degradation if you 

observe unusually large variation in replicate analyses. 

The report for RR21 was mailed the week of Nov 1, 2004. If you find your results for RR21 unsatisfactory, 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: 301-948-3.730, or e-mail: 

srminfo@nist.gov ). 

If you have any questions or concerns about the Vitamin C Micronutrients Measurement Quality Assurance 

Program please contact Jeanice Brown Thomas at tel: 301-975-3120, fax: 301-977-0685, or 

e-mail: jbthomas@nist.gov. 

We ask that you return your results for these RR22 samples before March 2, 2005. We would appreciate 

receiving your results as soon as they become available. Please use the attached form. Your results will be 

kept confidential. 

· ce 

ean1'~ Brown Thomas ~ il~ Analytical Chemistry Division 

Chemical Science and Technology Laboratory 

Enclosures: Protocols, Preparation and Analysis of Control Materials and Analysis of Test Samples 

RR22 Report Form for Ascorbic Acid Solid Control Material Preparation 

RR22 Report Form for Control Material and Test Sample Analyses 

N•SI 

E2
 

 

 

 

 

 

 

 

 

Micronutrient Measurement Quality Assurance Program for
 

Vitamin C
 

Please Read Through Completely BEFORE Analyzing Samples 

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

The ascorbic acid solid control material (in the amber vial) should be prepared and used in the 

following manner: 

1)		 Prepare at least 500 mL of 5% mass fraction metaphosphoric acid (MPA) in distilled water. This 

solution will be referred to as the “Diluent” below. 

2)		 Weigh 0.20 to 0.22 g of the ascorbic acid solid control material to 0.0001 g (if possible), dissolve 

it in the Diluent in a 100 mL volumetric flask, and dilute with the Diluent to the 100 mL mark. 

Weigh the amount of Diluent added to 0.1 g. Record the weights. The resulting material will be 

referred to as the “Stock Solution” below. 

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

Dilute Solution 1: Weigh 0.500 mL of the Stock Solution to 0.0001 g into a 100 mL volumetric 

flask; dilute with Diluent to the 100 mL mark. Record the weight. 

Dilute Solution 2: Weigh 0.250 mL of the Stock Solution to 0.0001 g into a 100 mL volumetric 

flask; dilute with Diluent to the 100 mL mark. Record the weight. 

Dilute Solution 3: Weigh 0.125 mL of the Stock Solution to 0.0001 g into a 100 mL volumetric 

flask; dilute with Diluent to the 100 mL mark. Record the weight. 

4)		 Calculate and record the total ascorbic acid concentrations, [TAA], in these Dilute Solutions. 

If you follow the above gravimetric preparation directions, the [TAA] in μmol/L is calculated: 

(g Stock Solution in Dilute Solution 	 ) (⋅ g AA in Stock Solution )⋅(56785 mol/g μ ⋅ L) [TAA] DS = (g AA in Stock Solution ) + (g Diluent in Stock Solution)

For example, if you prepared the Stock Solution with 0.2000 g of solid ascorbic acid and 103.0 g 

of Diluent, then 0.5 mL of the Stock Solution should weigh (0.2+103)/200 = 0.52 g and 

[TAA]DS1 = (0.52 g)(0.2 g)∙(56785 μmol/g·L)/(0.2 + 103 g) = 57.2 μmol/L. Likewise, 0.25 mL 

of the Stock Solution should weigh 0.26 g and [TAA]DS2 = 28.4 μmol/L and 0.125 mL should 

weigh 0.13 g and [TAA]DS3 = 14.2 μmol/L. 

5)		 Measure the ultraviolet absorbance spectrum of Dilute Solution 1 against the Diluent as the blank 

using paired 1 cm path length cuvettes. Record the absorbance at 242, 243, 244, and 245 nm. 

Record the maximum absorbance (Amax) within this region. Record the wavelength (λmax) at 

which this maximum occurs. 

The extinction coefficient (E1%) of ascorbic acid at λmax (using a cell with a 1 cm path length) of 

Dilute Solution #1 can be calculated: 

E3
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

1% dL (A max )⋅	 ((g AA in Stock Solution ) + (g Diluent in Stock Solution )) E ( ) = g ⋅ cm (g Stock Solution in Dilute Solution 1)⋅(g AA in Stock Solution)

If your spectrophotometer is properly calibrated, λmax should be between 243 and 244 nm and 

E1% should be 550 ± 30 dL/g·cm. If they are not, you should calibrate the wavelength and/or 

absorbance axes of your spectrophotometer and repeat the measurements. 

6)		 Measure and record the concentration of total ascorbic acid in all three dilute solutions and in the 

5% MPA Diluent in duplicate using exactly the same method that you will use for the serum 

control materials and test samples, including any enzymatic treatment. We recommend that you 

analyze these solutions in the following order: Diluent, Dilute Solution 1, Dilute Solution 2, 

Dilute Solution 3, Dilute Solution 3, Dilute Solution 2, Dilute Solution 1, Diluent. 

a)		 Compare the values of the duplicate measurements. Are you satisfied that your measurement 

precision is adequate? 

b)		 Compare the measured with the calculated [TAA] values. This is most conveniently done by 

plotting the measured values on the y-axis of a scatterplot against the calculated values on the 

x-axis. The line through the four {calculated, measured} data pairs should go through the 

origin with a slope of 1.0. Are you satisfied with the agreement between the measured and 

calculated values? 

Do not analyze the serum control materials or test samples until you are satisfied that your 

system is performing properly! 

7)		 Once you have confirmed that your system is properly calibrated, analyze the serum control 

materials (see protocol below). The target values for these materials are:
	

Control #1: 8.5 ±0.5 μmol/L of sample
	

Control #2: 28.1 ±1.0 μmol/L of sample.
	

If your measured values are not close to these target values, please review your sample 

preparation procedure and whether you followed exactly the same measurement protocol the 

solutions prepared from the solid control material as you used for these serum controls. If the 

protocols differ, please repeat from Step 6 using the proper protocol. If the proper protocol was 

used, your measurement system may not be suitable for MPA-preserved samples. Please contact 

us: 301-975-3120 or Jeanice.BrownThomas@NIST.gov. 

Do not analyze the test samples until you are satisfied that your system is performing properly 

and is suitable for the analysis of MPA-preserved serum! 

Protocol for Analysis of the Serum Control Materials and Test Samples 

The serum control materials and test samples are in sealed ampoules. They were prepared by adding 

equal volumes of 10% MPA 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 ascorbic acid should be reported. 

The serum control materials and test samples should be defrosted by warming at 20 °C for not more 

than 10 min otherwise some irreversible degradation may occur. 

Each serum test sample contains between 0.0 and 80.0 μmol of total ascorbic acid/L of solution. The 

total ascorbic acid in each ampoule should be measured in duplicate. Please report your results in 

μmol/(L of the sample solution) rather than μmol/(L of serum NIST used to prepare the sample). 

E4
 

 

Participant #: Date: 

Vitamin C Round Robin 22 

NIST Micronutrient Measurement Quality Assurance Program 

Preparation and Validation of Ascorbic Acid Solid Control Material 

STOCK SOLUTION 

Mass of ascorbic acid in the Stock Solution ..................................................__________ g 

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

DILUTE SOLUTION 1 

Mass of added stock solution (0.5 mL) ..........................................................__________ g 

Mass of 5% MPA Diluent 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
	

Absorbance of Dilute Solution 1 at 245 nm...................................................__________ AU
	

Absorbance of Dilute Solution absorbance maximum ..................................__________ AU
	

Wavelength of maximum absorbance............................................................__________ nm
	

Calculated E1% ...............................................................................................__________ dL/g·cm
	

Calculated [TAA]DS1......................................................................................__________ μmol/L
	

DILUTE SOLUTION 2 

Mass of added stock solution (0.25 mL) ........................................................__________ g 

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

Calculated [TAA]DS2......................................................................................__________ μmol/L
	

DILUTE SOLUTION 3 

Mass of added stock solution (0.125 mL) ......................................................__________ g 

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

Calculated [TAA]DS3......................................................................................__________ μmol/L
	

Please return before March 2, 2005 to: 

MMQAP Fax: 301-977-0685 

100 Bureau Drive, Stop 8392 Email: david.duewer@nist.gov 

Gaithersburg, MD 20899-8392 

E5
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Participant #: Date: 

Vitamin C Round Robin 22 

NIST Micronutrient Measurement Quality Assurance Program
 

Analysis of Control Materials and Test Samples
 

Sample Replicate 1 Replicate 2 Units
 

Dilute Solution 1 μmol/L of Dilute Solution 

Dilute Solution 2 μmol/L of Dilute Solution 

Dilute Solution 3 μmol/L of Dilute Solution 

5% MPA Diluent μmol/L of Diluent 

μmol/L of Sample Serum Control #1 

Target: 8.5 ±0.5 μmol/L 

μmol/L of Sample Serum Control #2 

Target: 28.1 ±1.0 μmol/L 

Serum Test Sample #23 μmol/L of Sample 

Serum Test Sample #33 μmol/L of Sample 

Serum Test Sample #42 μmol/L of Sample 

Serum Test Sample #70 μmol/L of Sample 

Were samples frozen upon receipt? Yes | No 

Analysis method: HPLC-EC | HPLC-Fluor DAB | HPLC-OPD | HPLC-UV | AO-OPD | Other
	

If “Other”, please describe:
	

COMMENTS: 

Please return before March 2, 2005 to:
	

MMQAP Fax: 301-977-0685 

100 Bureau Drive, Stop 8392 Email: david.duewer@nist.gov 

Gaithersburg, MD 20899-8392 

E6
 

 

 

 

Participant #: ________ Date: _____________ 

Vitamin C Round Robin 22
 

NIST Micronutrients Measurement Quality Assurance Program
 

Packing List and Shipment Receipt Confirmation Form
 

This box contains one vial each of the following seven VitC M2QAP samples: 

Sample Form 

VitC #23 Liquid frozen (1:1 serum:10% MPA) 

VitC #33 Liquid frozen (1:1 serum:10% MPA) 

VitC #42 Liquid frozen (1:1 serum:10% MPA) 

VitC #70 Liquid frozen (1:1 serum:10% MPA) 

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

Control #2 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 the samples arrived frozen 

4) Store the samples 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 of the vials intact? Yes | No 

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

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

4) Did the samples 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 is appreciated. 

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 RR22 

The following two 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
UNITED STATES DEPARTMENT OF COMMERCE 

National Institute of Standards and Technology 

Gaithersburg, Maryland 20899-CXXl1 

April 14, 2005 

Dear Colleague: 

Enclosed is the summary report of the results for Round Robin 22 (RR22) 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 0.74x interquartile range and the estimate coefficients of 

variation ( eCV) are defined as 1 OOx eSD/median. 

RR 22 consists of four test samples (#23, #33, #42, and #70), two serum control 

materials, and one solid control material for preparation ofTAA 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. 

Samples for the second vitamin C round robin study (RR 23) for the 2005 Vitamin C in Serum 

QA Program will be shipped (during the week of May 16). If you have questions or concerns 

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; or fax: 301-

977-0685. 

Sincerely, 

· ce Brown Thomas 

arch Chemist 

Analytical Chemistry Division 

Chemical Science and Technology Laboratory 

Enclosures 

N•SI 

F2
 

 

 

 

 

 

 

 

 

 

 

 

 

The NIST M2QAP Vitamin C Round Robin 22 (RR22) report consists of 

Page “Individualized” Report 

1 Summarizes your reported values for the nominal 55 mmol/L solution you prepared from the 

ascorbic acid solid control sample, the two serum control samples, and the four serum test 

samples. 

2 Graphical summary of your RR 22 sample measurements. 

Page “All Lab” Report 

1 A tabulation of results and summary statistics for Total Ascorbic Acid [TAA] in the RR22 

samples and control/calibration solutions. 

Serum-based Samples. Two serum controls and four unknowns were distributed in RR22. 

CS1 SRM 970 level 1, ampouled in mid-1998. 

CS2 SRM 970 level 2, ampouled in mid-1998. 

S22:1 Serum 23, ampouled in late 2001, previously distributed as sample S17:1 (RR17, Sep-02), 

S19:2 (RR19, Sep-03), and S21:2 (Sep-04). An augmented serum. 

S22:2 Serum 33, ampouled in late 2001, previously distributed as sample S17:2 (RR17, Sep-02), 

S18:1 (RR18, Mar-03) and S20:1 (RR20, Mar-04). An augmented serum. 

S22:3 Serum 42, ampouled in late 2001, previously distributed as sample S18:2 (RR18, Mar-03), 

S19:3 (RR19, Sep-03) and S21:3 (RR21, Sep-04). An augmented serum. 

S22:4 Serum 70, SRM 970 level 2, ampouled in mid-1998. This material was distributed with 

identification in RR11 (Oct-98) and RR12 (Mar-99) and as samples S13-2 (RR13, Mar-00), 

S14-4 (RR14, Mar-01), S15:2 (RR15, Sep-01), S18:3 (RR18, Mar-03), and 

S20:4 (RR20, Mar-04). An augmented serum. 

Results. 

1)		 All participants who prepared the four control/calibration solutions (the three “Dilute Solutions” and 

the 5% MPA “Diluent”) did so correctly. The criteria used to evaluate this success are: the density of 

the 5% MPA (≈1.03 g/mL), the observed wavelength maximum of “Dilute Solution 1”(≈244 nm), the 

observed absorbance at that maximum (≈0.55 OD), the calculated E1% of Solution 1”(≈550 dL/g·cm). 

2)		 Judging from the calibration parameters calculated for the control/calibration solutions (intercepts 

close to 0.0 and slopes close to 1.0), the measurement systems for most participants are well 

calibrated, although the slope for one participant was 11% lower than expected and the intercept for 

another participant was significantly different from zero. 

3)		 Several participants reported values for high-level control that were well outside the target range of 

26 μmol/L to 30 μmol/L. If the measured values for the control samples are not close to the targets, 

even if your measured and calculated values for the calibration solutions agree, there is a problem 

with your measurement system. 

4)		 There is no evidence of sample degradation with any of the samples distributed. 

F3
 

 

 

Appendix G. “All-Lab Report” for RR22 

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
Micronutrients Measurement Quality Assurance Program for Total Ascorbic Acid 

"Round Robin" 22 - March 2005 

Control / Calibration Samples MPA Dilute Solution 1 Samples 

G2

Density 

Lab Date Dil:1 Dil:2 Dil:3 Dil:1 Dil:2 Dil:3 MPA Inter Slope R2 SEE g/mL λmax Amax E1% CS#1 CS#2 S22:1 S22:2 S22:3 S22:4 CS#

VC-MA 08/03/05 56.4 28.5 14.0 59.9 30.6 15.3 0.0 0.21 1.06 1.000 0.2 1.032 243. 0.5591 562.9 8.6 29.0 9.6 22.7 35.6 29.4 7

VC-MB 02/03/05 56.6 28.0 14.3 53.7 26.1 13.7 0.0 -0.07 0.95 1.000 0.3 1.032 244. 0.5612 563.3 8.3 28.9 7.7 22.0 35.1 28.4 8

VC-MC 29/11/04 57.2 27.5 13.5 50.8 25.5 12.5 0.0 0.40 0.89 0.999 0.6 1.030 243. 0.5553 551.1 8.3 27.0 10.3 23.9 37.6 27.0 8

VC-ME 14/03/03 56.7 28.3 14.0 57.9 29.5 14.8 0.0 0.33 1.02 1.000 0.4 1.033 243. 0.5315 532.5 8.4 27.7 10.2 22.6 31.3 28.2 7.

VC-MG 08/02/05 57.6 29.1 14.5 58.4 28.1 13.3 0.0 -0.83 1.02 0.999 1.0 1.033 243.9 0.5700 561.6 8.7 30.4 11.4 24.7 40.6 34.1 9

VC-MH 13/01/05 62.5 31.2 15.2 62.9 31.8 15.7 0.2 0.34 1.00 1.000 0.2 1.030 244. 0.6120 556.2 8.3 27.9 8.5 22.5 34.3 28.2 7

VC-MI 12/01/05 56.0 28.0 14.3 55.2 26.8 13.4 1.0 0.15 0.97 0.999 1.0 1.033 7.1 26.5 4.1 16.1 26.4 26.0 7

VC-MJ 15/12/04 58.7 28.8 15.0 57.4 30.4 15.0 0.4 0.80 0.97 0.998 1.3 1.023 10.3 27.2 11.6 22.6 31.1 26.5 9

VC-MK 25/02/05 58.9 28.4 13.9 65.2 35.2 19.8 1.5 3.40 1.07 0.996 2.2 1.032 244. 0.5854 564.0 12.4 35.3 14.6 29.7 41.3 35.0 8.

VC-MT 01/03/05 56.7 27.8 14.4 56.9 28.4 13.9 0.0 -0.12 1.01 1.000 0.5 1.032 244. 0.5603 561.3 8.7 28.9 9.5 21.2 35.7 29.8 8

VC-MY 22/02/05 11.5 49.8 11.1 34.5 54.9 46.0 11

10 10 10 10 10 10 10 10 8 8 8 11 11 11 11 11 11 1

57.7 28.5 14.3 57.8 29.2 14.7 0.3 1.031 243.6 0.5669 556.6 9.1 30.8 9.9 23.8 36.7 30.8 8

1.9 1.0 0.5 4.2 2.9 2.0 0.5 0.003 0.5 0.0236 10.7 1.6 6.7 2.7 4.7 7.4 5.8 1

56.0 27.50 13.5 50.8 25.47 12.5 0.0 1.023 243.0 0.5315 532.5 7.1 26.5 4.1 16.1 26.4 26.0 7

56.6 27.98 14.0 55.6 27.09 13.4 0.0 1.031 243.0 0.5582 554.9 8.3 27.4 9.0 22.2 32.8 27.6 7

56.9 28.32 14.3 57.6 28.97 14.4 0.0 1.032 244.0 0.5608 561.5 8.6 28.9 10.2 22.6 35.6 28.4 8

58.5 28.73 14.5 59.5 30.53 15.2 0.3 1.033 244.0 0.5739 563.0 9.5 29.7 11.3 24.3 39.1 31.9 9

62.5 31.19 15.2 65.2 35.21 19.8 1.5 1.033 244.0 0.6120 564.0 12.4 49.8 14.6 34.5 54.9 46.0 11

0.9 0.6 0.4 3.5 2.8 1.4 0.0 0.002 0.1 0.0109 3.3 0.4 2.1 1.8 1.9 6.4 2.1 1

2 2 3 6 10 10 0.19 0.03 1.9 0.6 5 7 18 8 18 7 1

MADe eSD 

CV CV 

Median Median 

%75 %75 

Max Max 

Min Min 

%25 %25 

N N 

Average Average 

SD SD 

Gravimetric, μmol/L Measured, μmol/L Calibration Parameters Spectrophotometry Measured, μmol/L 

All Lab Report 
Appendix H. Representative “Individualized Report” for RR22 

Each participant in RR22 received an “Individualized Report” reflecting their reported 

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

“VC-MA”. 

H1
 

Set 1 of 11 

Vitamin C "Round Robin" 22 Report: Participant VC-MA
 

Date RR Method 

12/12/02 17 HPLC-EC 

03/20/03 18 HPLC-EC 

11/13/03 19 HPLC-EC 

02/23/04 20 HPLC-EC 

09/13/04 21 HPLC-EC 

03/08/05 22 HPLC-EC 

MPA Dilute Solution 1 Control/Calibration Solutions 

Density Spectrophotometry Ymeas = Inter + Slope* Xgrav 

g/mL 

1.026 

1.026 

1.026 

1.031 

1.030 

1.034 

λmax Amax E1% 

242.0 0.552 551.0 

244.0 0.509 563.1 

243.0 0.584 561.9 

243.0 0.552 560.7 

244.0 0.555 562.2 

243.0 0.559 562.9 

Inter Slope R2 SEE 

-0.3 1.06 1.000 0.49 

-0.1 1.02 1.000 0.18 

1.1 1.03 0.998 1.24 

-0.4 1.05 1.000 0.65 

-0.1 0.99 1.000 0.10 

0.2 1.06 1.000 0.24 

Mean 1.029 243.2 0.55 560.3 0.48 

SD 0.003 0.8 0.02 4.6 0.42 

CV 0.32 0.31 4.4 0.8 

[TAA] mmol/Lsample 

3 27.2 0.4 1.6 

4 9.3 0.3 0.4 

4 23.5 0.5 0.8 

4 35.0 0.3 1.3 

8 26.5 0.4 2.0 

Date RR Sample 

02/23/04 20 CS#1 

09/13/04 21 CS#1 

03/08/05 22 CS#1 

02/23/04 20 CS#2 

09/13/04 21 CS#2 

03/08/05 22 CS#2 

12/12/02 17 S17:1 

11/13/03 19 S19:2 

09/13/04 21 S21:2 

03/08/05 22 S22:1 

12/12/02 17 S17:2 

03/20/03 18 S18:1 

02/23/04 20 S20:1 

03/08/05 22 S22:2 

03/20/03 18 S18:2 

11/13/03 19 S19:3 

09/13/04 21 S21:3 

03/08/05 22 S22:3 

09/23/98 11 S11:2 

04/02/99 12 S12:2 

09/17/01 13 S13:2 

09/27/01 14 S14:4 

09/18/01 15 S15:2 

03/20/03 18 S18:3 

02/23/04 20 S20:4 

03/08/05 22 S22:4 

Rep1 Rep2 Fadj Mean SDdup 

7.8 8.0 1.0 7.9 0.1 

8.1 7.9 1.0 8.0 0.1 

8.5 8.7 1.0 8.6 0.1 

N Mean SDrepeat SDreprod 

3 8.2 0.1 0.4 

25.8 26.2 1.0 26.0 0.3 

26.2 27.2 1.0 26.7 0.7 

29.0 29.0 1.0 29.0 0.0 

9.9 9.1 1.0 9.5 0.6 

9.2 9.1 1.0 9.2 0.1 

8.8 8.7 1.0 8.7 0.1 

9.6 9.6 1.0 9.6 0.0 

23.3 23.4 1.0 23.4 0.1 

22.7 23.7 1.0 23.2 0.7 

25.1 24.1 1.0 24.6 0.7 

22.7 22.7 1.0 22.7 0.0 

35.1 36.0 1.0 35.6 0.6 

35.9 35.8 1.0 35.9 0.1 

33.2 32.9 1.0 33.0 0.2 

35.7 35.6 1.0 35.6 0.1 

49.2 51.4 0.5 25.2 0.8 

47.7 47.0 0.5 23.7 0.2 

27.6 27.7 1.0 27.7 0.1 

25.7 26.4 1.0 26.0 0.5 

25.4 25.6 1.0 25.5 0.2 

28.8 29.2 1.0 29.0 0.3 

25.9 25.2 1.0 25.5 0.5 

29.4 29.4 1.0 29.4 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 Fax: (301) 977-0685 

Gaithersburg, MD 20899-8392 USA Email: david.duewer@nist.gov 

Individualized Report Page 1/2 

H2
 

 

 

[Total Ascorbic Acid], μmol/L 

Set 1 of 11 

Vitamin C "Round Robin" 22 Report: Participant VC-MA 

Total Ascorbic Acid 

S17:1S19:2S21:2S22:1S17:2S18:1S20:1S22:2S18:2S19:3S21:3S22:3 S11:2S12:2S13:2S14:4S15:2S18:3S20:4S22:4 

Your [Total Ascorbic Acid], μmol/L

Median [Total Ascorbic Acid], μmol/L 

Apparent Precision, SD 

Concordance, SD 

3rd Quartile (75%) You, RR 22
 NIST, RR 22
 Median (50%) You, RR 17-21
 Others, RR 22
 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 

S21:1 Serum 23, previously distributed in RRs 17, 19, and 21
 

S21:2 Serum 33, previously distributed in RRs 17, 18, and 20
 

S21:3 Serum 42, previously distributed in RRs 18, 19, and 21
 

S21:4 SRM 970 Level 2, previously distributed in RRs 11, 12, 13, 14, 15, 18, and 20
 

Individualized Report Page 2/2 

H3