title: Analysis of reagent lot-to-lot comparability tests in five immunoassay items.
abstract: We investigated the degree of lot-to-lot reagent variation for 5 common immunoassay items. We measured the commercial as well as in-house controls for α-fetoprotein (AFP), ferritin, CA19-9, quantitative hepatitis B surface antigen (HBsAg), and hepatitis B surface antibody (anti-HBs) 10 times each by using both the old and the new lot of reagents whenever a reagent lot was changed, over a period of 10 months. The differences in the mean control values, the percent difference (% difference), and the difference to between-run standard deviation ratio (D:SD ratio) between successive lots were calculated. The % difference in mean control values between 2 reagent lots ranged from 0.1 to 17.5% for AFP, 1.0 to 18.6% for ferritin, 0.6 to 14.3% for CA19-9, 0.6 to 16.2% for HBsAg, and 0.1 to 17.7% for anti-HBs except negative controls of HBsAg and anti-HBs. The maximum D:SD ratios between 2 lots were 4.37 for AFP, 4.39 for ferritin, 2.43 for CA19-9, 1.64 for HBsAg, and 4.16 for anti-HBs. Thus, we have experienced extensive variability in lot-to-lot reagent variation for 5 immunoassay items, indicating that reagent lot-to-lot comparability tests should be continuously performed and that laboratories should determine their own acceptance criteria for each item.
authors.affiliation: Department of Laboratory Medicine, Hallym University College of Medicine, Seoul, 150-719, Korea. hskim0901@empal.com
authors.forename: Hyun Soo
authors.initials: HS
authors.lastname: Kim
authors.forename: Hee Jung
authors.initials: HJ
authors.lastname: Kang
authors.forename: Dong Hee
authors.initials: DH
authors.lastname: Whang
authors.forename: Seong Gyu
authors.initials: SG
authors.lastname: Lee
authors.forename: Min Jeong
authors.initials: MJ
authors.lastname: Park
authors.forename: Ji-Young
authors.initials: JY
authors.lastname: Park
authors.forename: Kyu Man
authors.initials: KM
authors.lastname: Lee
mesh_terms: D018395:CA-19-9 Antigen / Q000032:analysis; D002138:Calibration; D005293:Ferritins / Q000032:analysis; D006510:Hepatitis B Antibodies / Q000032:analysis; D006514:Hepatitis B Surface Antigens / Q000032:analysis; D006801:Humans; D007118:Immunoassay / Q000379:methods* / Q000592:standards*; D007202:Indicators and Reagents / Q000032:analysis*; D011786:Quality Control; D011933:Reagent Kits, Diagnostic / Q000592:standards*; D000509:alpha-Fetoproteins / Q000032:analysis
chemical_list: D018395:CA-19-9 Antigen; D006510:Hepatitis B Antibodies; D006514:Hepatitis B Surface Antigens; D007202:Indicators and Reagents; D011933:Reagent Kits, Diagnostic; D000509:alpha-Fetoproteins; D005293:Ferritins