title: Reevaluation of serum-plasma differences in total cholesterol concentration.
abstract: We measured total cholesterol levels in serum and disodium ethylenediaminetetraacetate (EDTA) plasma samples obtained from 84 healthy medical students during their entrance physical examinations and 48 adults from a cholesterol screening program who were resampled because they had initial values of 5.17 mmol/L (200 mg/dL) or higher. Plasma cholesterol concentrations were 4.7% lower than those in serum samples. The plasma and serum values were highly correlated (r = .994), however, suggesting that measurements in EDTA plasma can be converted readily to equivalent serum concentrations. Thus, the negative bias in EDTA plasma was greater than the 3% value cited in the National Cholesterol Education Program Guidelines, probably because the amount of EDTA now provided in evacuated blood collection tubes is 50% greater than in those used when the 3% value was established. These findings are relevant to the interpretation of both cholesterol screening measurements and follow-up lipoprotein analyses.
authors.affiliation: Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, Md.
authors.forename: T
authors.initials: T
authors.lastname: Cloey
authors.forename: P S
authors.initials: PS
authors.lastname: Bachorik
authors.forename: D
authors.initials: D
authors.lastname: Becker
authors.forename: C
authors.initials: C
authors.lastname: Finney
authors.forename: D
authors.initials: D
authors.lastname: Lowry
authors.forename: W
authors.initials: W
authors.lastname: Sigmund
mesh_terms: D000328:Adult; D002784:Cholesterol / Q000097:blood*; D004492:Edetic Acid; D005069:Evaluation Studies as Topic; D006493:Heparin; D006801:Humans; D008875:Middle Aged; D010949:Plasma / Q000032:analysis*; D012044:Regression Analysis
chemical_list: D006493:Heparin; D002784:Cholesterol; D004492:Edetic Acid