2010年11月
Commutability of National Institute of Standards and Technology standard reference material 1955 homocysteine and folate in frozen human serum for total folate with automated assays
ANNALS OF CLINICAL BIOCHEMISTRY
- 巻
- 47
- 号
- 6
- 開始ページ
- 541
- 終了ページ
- 548
- 記述言語
- 英語
- 掲載種別
- DOI
- 10.1258/acb.2010.010094
- 出版者・発行元
- SAGE PUBLICATIONS INC
Background: The aim of the present study was to evaluate standard reference material (SRM) 1955 commutability as a reference material for serum folate using automated methods. We also designed so as to reduce the intermethod variability present in different automated methods.
Methods: Using a microbiological assay related to the 'information value' of SRM 1955 as a comparison method, we investigated the possibility of standardization for the assay values of serum folate as measured by the automated methods (Access, Centaur and Elecsys). In the assay of 50 patient sera by these automated methods, we corrected observed values by the SRM 1955 and compared with comparison values.
Results: The observed values of SRM 1955 Levels I, II and III were within or outside (but near) a 95% prediction interval obtained from patient sera by the automated methods. The normalized residuals obtained from SRM 1955 were within +/- 3.0 (in SD units), which enabled us to conclude that the SRM 1955 had a physicochemical characterization similar to native serum. Twelve patients were assessed as hypofolataemia (<6.0 ng/mL) and 38 patients as normal (>= 6.0 ng/mL). Before correction, folate levels in six of 12 patients were lower than 6.0 ng/mL, and those in seven of 38 patients were higher than 6.0 ng/mL with the automated methods. After correction, low levels were found in four of 12 patients, and normal levels were found in 33 of 38 patients.
Conclusions: The use of SRM 1955 would help to reduce the intermethod variability present in different automated methods for serum folate measurement.
Methods: Using a microbiological assay related to the 'information value' of SRM 1955 as a comparison method, we investigated the possibility of standardization for the assay values of serum folate as measured by the automated methods (Access, Centaur and Elecsys). In the assay of 50 patient sera by these automated methods, we corrected observed values by the SRM 1955 and compared with comparison values.
Results: The observed values of SRM 1955 Levels I, II and III were within or outside (but near) a 95% prediction interval obtained from patient sera by the automated methods. The normalized residuals obtained from SRM 1955 were within +/- 3.0 (in SD units), which enabled us to conclude that the SRM 1955 had a physicochemical characterization similar to native serum. Twelve patients were assessed as hypofolataemia (<6.0 ng/mL) and 38 patients as normal (>= 6.0 ng/mL). Before correction, folate levels in six of 12 patients were lower than 6.0 ng/mL, and those in seven of 38 patients were higher than 6.0 ng/mL with the automated methods. After correction, low levels were found in four of 12 patients, and normal levels were found in 33 of 38 patients.
Conclusions: The use of SRM 1955 would help to reduce the intermethod variability present in different automated methods for serum folate measurement.
- リンク情報
-
- DOI
- https://doi.org/10.1258/acb.2010.010094
- CiNii Articles
- http://ci.nii.ac.jp/naid/80021436682
- PubMed
- https://www.ncbi.nlm.nih.gov/pubmed/20926465
- Web of Science
- https://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=JSTA_CEL&SrcApp=J_Gate_JST&DestLinkType=FullRecord&KeyUT=WOS:000285270100007&DestApp=WOS_CPL
- ID情報
-
- DOI : 10.1258/acb.2010.010094
- ISSN : 0004-5632
- eISSN : 1758-1001
- CiNii Articles ID : 80021436682
- PubMed ID : 20926465
- Web of Science ID : WOS:000285270100007