Variability and classification accuracy of serial high-sensitivity C-reactive protein measurements in healthy adults

Clin Chem. 2001 Mar;47(3):444-50.


Background: Increased concentrations of high-sensitivity C-reactive protein (hs-CRP), a marker of systemic inflammation, are associated with increased risk for coronary heart disease. Because of its relationship to inflammation, hs-CRP has considerable biologic variation. This study was carried out to characterize CRP variation and to compare it to another risk factor, total serum cholesterol.

Methods: One hundred thirteen individuals were scheduled to have five measurements each of hs-CRP and total cholesterol carried out at quarterly intervals over a 1-year period. Variations of hs-CRP and total cholesterol were characterized, and classification accuracy was described and compared for both.

Results: The relative variation was comparable for hs-CRP and total cholesterol. When classified by quartile, 63% of first and second hs-CRP measurements were in agreement; for total cholesterol it was 60%. Ninety percent of hs-CRP measurements were within one quartile of each other. This relationship was not altered by the use of log-transformed hs-CRP data.

Conclusion: hs-CRP has a degree of measurement stability that is similar to that of total cholesterol.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adult
  • Aged
  • Analysis of Variance
  • C-Reactive Protein / analysis*
  • Cholesterol / blood
  • Female
  • Humans
  • Immunoassay
  • Longitudinal Studies
  • Male
  • Middle Aged
  • Nephelometry and Turbidimetry
  • Reference Values
  • Sex Factors


  • C-Reactive Protein
  • Cholesterol