Multi-center validation of the Response Biomedical Corporation RAMP NT-proBNP assay with comparison to the Roche Diagnostics GmbH Elecsys proBNP assay

Clin Chim Acta. 2007 Nov-Dec;386(1-2):20-4. doi: 10.1016/j.cca.2007.07.015. Epub 2007 Jul 25.


Background: NT-proBNP measurements aid in the evaluation of patients with suspected heart failure (HF) and may facilitate risk stratification in patients with HF and acute coronary syndrome (ACS). Point-of-care (POC) assays may provide more timely results and potentially improve patient outcomes.

Methods: We evaluated the analytical performance of the Response Biomedical Corporation whole blood RAMP amino-terminal pro-B type natriuretic peptide (NT-proBNP) POC assay compared to the Roche Elecsys proBNP (NT-proBNP) assay.

Results: Intra-day and total imprecision (% CV) ranged from 5.5% to 10.3% at 140, 449 and 1675 ng/L. The lowest concentration that yields a 20% CV was 57 ng/L. The lower limit of detection was 18 ng/L. The upper limit of linearity was validated to 23,428 ng/L with an average recovery of 95%. Correlation by Passing and Bablok regression yielded RAMP=1.01 Elecsys+14.6, r=0.98 (n=540; range of Elecsys values <5 to >35,000). Concordance of RAMP versus Elecsys using cut-offs of 125 ng/L for subjects <75 years and 450 ng/L for subjects > or =75 was 92% (95% CI 89-94%) for a group consisting of 127 apparently healthy individuals and 208 non-healthy subjects without HF, and 99% (95% CI 97-100%) for patients with HF, using the New York Heart Association (NYHA) functional classification. Overall, 80%, 87%, 97% and 100% of the RAMP results and 77%, 85%, 96% and 100% of the Elecsys results were greater than the age appropriate cut-off for NYHA I, II, III or IV groups. For both the RAMP and Elecsys results, the median NT-proBNP value was statistically correlated (increasing) with NYHA I, II, III or IV groups, respectively (p<0.0001), with no significant difference between the two methods.

Conclusions: The POC Response Biomedical RAMP NT-proBNP assay provides comparable results that measured on the FDA cleared Roche Elecsys central laboratory platform.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't
  • Validation Study

MeSH terms

  • Acute Disease
  • Adult
  • Aged
  • Aged, 80 and over
  • Biological Assay / methods*
  • Biomarkers / analysis
  • Coronary Disease / blood*
  • Coronary Disease / diagnosis
  • Female
  • Heart Failure / blood
  • Heart Failure / diagnosis
  • Humans
  • Male
  • Middle Aged
  • Natriuretic Peptide, Brain / blood*
  • Peptide Fragments / blood*
  • Point-of-Care Systems*
  • Reagent Kits, Diagnostic*
  • Reference Values
  • Reproducibility of Results
  • Sample Size
  • Sensitivity and Specificity
  • Time Factors


  • Biomarkers
  • Peptide Fragments
  • Reagent Kits, Diagnostic
  • pro-brain natriuretic peptide (1-76)
  • Natriuretic Peptide, Brain