Impact of quality control on accuracy in enzyme immunoassay testing for human immunodeficiency virus type 1 antibodies.
OBJECTIVE
To assess use of quality control (QC) material, supplemental to internal kit controls (calibrators), as protection against errors in enzyme immunoassay testing for human immunodeficiency virus type 1 antibodies.


METHODS
From August 1994 to January 1996, enzyme immunoassay testing accuracy was assessed for laboratories participating in the Centers for Disease Control and Prevention Model Performance Evaluation Program that provided information regarding their use of QC material. Error rates were examined for human immunodeficiency virus type 1 antibody-negative, strongly positive, and weakly positive samples.


RESULTS
The overall error rate with QC (2.20%) was significantly (P = .0023) lower than the error rate without QC (2.90%). With QC use there was a significant reduction in the relative risk of error for negative (P = .014) and weakly positive (P = .0067) samples. After multivariate analysis, use of QC lowered overall error rate by 29% (P = .0009). Laboratories not using QC were at increased risk of systematic error. Following the Clinical Laboratory Improvement Amendments of 1988 guidelines for QC material was relatively more protective against error than lower frequencies/number of levels.


CONCLUSIONS
Using QC protected against errors in enzyme immunoassay testing for human immunodeficiency virus type 1 antibodies. Two levels of QC should be used with each run as mandated by the Clinical Laboratory Improvement Amendments of 1988.
Division of Laboratory Systems, Public Health Practice Program Office, Centers for Disease Control and Prevention, Atlanta, GA 30341, USA.
J R
JR
Astles
H B
HB
Lipman
W O
WO
Schalla
S O
SO
Blumer
R J
RJ
Fehd
C
C
Smith
T L
TL
Hearn
D019411:Clinical Laboratory Techniques / Q000592:standards; D015483:HIV Antibodies / Q000032:analysis*; D015497:HIV-1 / Q000276:immunology*; D006801:Humans; D007124:Immunoenzyme Techniques / Q000592:standards*; D007753:Laboratories / Q000145:classification / Q000592:standards; D015999:Multivariate Analysis; D011786:Quality Control; D011933:Reagent Kits, Diagnostic / Q000592:standards*; D012680:Sensitivity and Specificity
D015483:HIV Antibodies; D011933:Reagent Kits, Diagnostic