Lupus anticoagulant testing: improvements in performance in a UK NEQASproficiency testing exercise after distribution of guidelines on laboratory methods

I. Jennings, Michael Greaves, I. J. Mackie, S. Kitchen, T. A. Woods, F. E. Preston, UK Natl External Quality Assessmen

Research output: Contribution to journalArticle

70 Citations (Scopus)

Abstract

Laboratory screening for lupus anticoagulant (LA) has been shown to be suboptimal in several studies. Guidelines have recently been published by an expert group for the British Committee for Standards in Haematology, in an attempt to standardize and improve screening procedures. The value of using screening tests conforming with these guidelines was investigated in a United Kingdom National External Quality Assessment Scheme (UK NEQAS) proficiency testing exercise. The correct diagnosis was achieved by 97% of laboratories for a LA-negative sample. However, 18.3% of centres reported a false-negative result for a sample from a LA-positive subject. A significantly higher proportion of centres that used methods conforming with the published guidelines achieved the correct diagnosis for this sample (P<0.002, chi-square test). A wide variety of screening tests were used by laboratories in this study. Within-method agreement could be improved by the use of a common normal pooled plasma to determine ratios. However, between-method agreement was not improved by this procedure. We conclude that adoption of methods compliant with national guidelines may improve the diagnosis of LA. There is a need, however, for reference and standardization materials to ensure further improvement in the accuracy of LA methods.

Original languageEnglish
Pages (from-to)364-369
Number of pages5
JournalBritish Journal of Haematology
Volume119
DOIs
Publication statusPublished - 2002

Keywords

  • lupus anticoagulant
  • laboratory diagnosis
  • proficiency testing
  • ANTIPHOSPHOLIPID SYNDROME
  • MONOCLONAL-ANTIBODIES
  • THROMBOPLASTIN
  • HEPARIN
  • RATIO
  • TIME

Cite this

Lupus anticoagulant testing: improvements in performance in a UK NEQASproficiency testing exercise after distribution of guidelines on laboratory methods. / Jennings, I.; Greaves, Michael; Mackie, I. J.; Kitchen, S.; Woods, T. A.; Preston, F. E.; UK Natl External Quality Assessmen.

In: British Journal of Haematology, Vol. 119, 2002, p. 364-369.

Research output: Contribution to journalArticle

Jennings, I. ; Greaves, Michael ; Mackie, I. J. ; Kitchen, S. ; Woods, T. A. ; Preston, F. E. ; UK Natl External Quality Assessmen. / Lupus anticoagulant testing: improvements in performance in a UK NEQASproficiency testing exercise after distribution of guidelines on laboratory methods. In: British Journal of Haematology. 2002 ; Vol. 119. pp. 364-369.
@article{31d0663196ba4ea5ac84ad77452ac94b,
title = "Lupus anticoagulant testing: improvements in performance in a UK NEQASproficiency testing exercise after distribution of guidelines on laboratory methods",
abstract = "Laboratory screening for lupus anticoagulant (LA) has been shown to be suboptimal in several studies. Guidelines have recently been published by an expert group for the British Committee for Standards in Haematology, in an attempt to standardize and improve screening procedures. The value of using screening tests conforming with these guidelines was investigated in a United Kingdom National External Quality Assessment Scheme (UK NEQAS) proficiency testing exercise. The correct diagnosis was achieved by 97{\%} of laboratories for a LA-negative sample. However, 18.3{\%} of centres reported a false-negative result for a sample from a LA-positive subject. A significantly higher proportion of centres that used methods conforming with the published guidelines achieved the correct diagnosis for this sample (P<0.002, chi-square test). A wide variety of screening tests were used by laboratories in this study. Within-method agreement could be improved by the use of a common normal pooled plasma to determine ratios. However, between-method agreement was not improved by this procedure. We conclude that adoption of methods compliant with national guidelines may improve the diagnosis of LA. There is a need, however, for reference and standardization materials to ensure further improvement in the accuracy of LA methods.",
keywords = "lupus anticoagulant, laboratory diagnosis, proficiency testing, ANTIPHOSPHOLIPID SYNDROME, MONOCLONAL-ANTIBODIES, THROMBOPLASTIN, HEPARIN, RATIO, TIME",
author = "I. Jennings and Michael Greaves and Mackie, {I. J.} and S. Kitchen and Woods, {T. A.} and Preston, {F. E.} and {UK Natl External Quality Assessmen}",
year = "2002",
doi = "10.1046/j.1365-2141.2002.03821.x",
language = "English",
volume = "119",
pages = "364--369",
journal = "British Journal of Haematology",
issn = "0007-1048",
publisher = "Wiley-Blackwell",

}

TY - JOUR

T1 - Lupus anticoagulant testing: improvements in performance in a UK NEQASproficiency testing exercise after distribution of guidelines on laboratory methods

AU - Jennings, I.

AU - Greaves, Michael

AU - Mackie, I. J.

AU - Kitchen, S.

AU - Woods, T. A.

AU - Preston, F. E.

AU - UK Natl External Quality Assessmen

PY - 2002

Y1 - 2002

N2 - Laboratory screening for lupus anticoagulant (LA) has been shown to be suboptimal in several studies. Guidelines have recently been published by an expert group for the British Committee for Standards in Haematology, in an attempt to standardize and improve screening procedures. The value of using screening tests conforming with these guidelines was investigated in a United Kingdom National External Quality Assessment Scheme (UK NEQAS) proficiency testing exercise. The correct diagnosis was achieved by 97% of laboratories for a LA-negative sample. However, 18.3% of centres reported a false-negative result for a sample from a LA-positive subject. A significantly higher proportion of centres that used methods conforming with the published guidelines achieved the correct diagnosis for this sample (P<0.002, chi-square test). A wide variety of screening tests were used by laboratories in this study. Within-method agreement could be improved by the use of a common normal pooled plasma to determine ratios. However, between-method agreement was not improved by this procedure. We conclude that adoption of methods compliant with national guidelines may improve the diagnosis of LA. There is a need, however, for reference and standardization materials to ensure further improvement in the accuracy of LA methods.

AB - Laboratory screening for lupus anticoagulant (LA) has been shown to be suboptimal in several studies. Guidelines have recently been published by an expert group for the British Committee for Standards in Haematology, in an attempt to standardize and improve screening procedures. The value of using screening tests conforming with these guidelines was investigated in a United Kingdom National External Quality Assessment Scheme (UK NEQAS) proficiency testing exercise. The correct diagnosis was achieved by 97% of laboratories for a LA-negative sample. However, 18.3% of centres reported a false-negative result for a sample from a LA-positive subject. A significantly higher proportion of centres that used methods conforming with the published guidelines achieved the correct diagnosis for this sample (P<0.002, chi-square test). A wide variety of screening tests were used by laboratories in this study. Within-method agreement could be improved by the use of a common normal pooled plasma to determine ratios. However, between-method agreement was not improved by this procedure. We conclude that adoption of methods compliant with national guidelines may improve the diagnosis of LA. There is a need, however, for reference and standardization materials to ensure further improvement in the accuracy of LA methods.

KW - lupus anticoagulant

KW - laboratory diagnosis

KW - proficiency testing

KW - ANTIPHOSPHOLIPID SYNDROME

KW - MONOCLONAL-ANTIBODIES

KW - THROMBOPLASTIN

KW - HEPARIN

KW - RATIO

KW - TIME

U2 - 10.1046/j.1365-2141.2002.03821.x

DO - 10.1046/j.1365-2141.2002.03821.x

M3 - Article

VL - 119

SP - 364

EP - 369

JO - British Journal of Haematology

JF - British Journal of Haematology

SN - 0007-1048

ER -