Background
Low concentration C-reactive protein (CRP) has favorable prognostic significance in patients with cardiovascular risks.
Conclusions
Roche wr-CRP and hs-CRP assays are highly concordant in determining low concentration CRP. Wr-CRP may be used as an alternative to hs-CRP assay on Roche Cobas c702 analyzer to assess the cardiovascular risk, considering its convenience and lower costs.
Methods
We compared the wr-CRP method with the hs-CRP method both on Roche Cobas c702 analyzer for the determination of low CRP concentration (<20 mg/L) including 200 patients treated in Cardiology Department in Beijing Tsinghua Changgung Hospital (Beijing, China) from December 2018 to March 2019.
Results
The two methods were highly correlated (Spearman's rho = 0.995). Deming regression was used to fit the regression analysis model, giving a slope of 1.058 with an intercept of 0.008. The median method difference (wr-CRP - hr-CRP) was 0.120 mg/L (95% CI, 0.086-0.200 mg/L), and the median percent differences were 7.34% (95% CI, 4.27%-8.47%). The percent bias between both methods at the given cutoff CRP values of 1, 3, and 10 mg/L evaluated by Deming regression was 6.60%, 6.07%, and 5.88%, respectively, all of which were less than the acceptable standard (12.50%). The percentage of sample results concordant by both methods for the risk stratification was 96.0% (kappa = 0.937, P < 0.001). Conclusions: Roche wr-CRP and hs-CRP assays are highly concordant in determining low concentration CRP. Wr-CRP may be used as an alternative to hs-CRP assay on Roche Cobas c702 analyzer to assess the cardiovascular risk, considering its convenience and lower costs.