Quality Assessment of Coaguchek Point-Of-Care International Normalized Ratio Monitors: A Note of Caution (Letters) (Letter to the Editor‪)‬

To the Editor: In a recent publication Poller et al. (1) described quality assessment (QA) of CoaguChek (CUC) point-of-care (POC) international normalized ratio (INR) monitors and compared 2 procedures. The study compared the proportion of 523 CUC monitors having unsatisfactory performance as indicated by either a 15% deviation of INR results from the INR assigned to 5 lyophilized QA plasmas or a 15% deviation from the overall median of INRs obtained on the monitors included in the survey. The INRs assigned to QA plasmas had been derived from a full calibration in compliance with WHO-recommended procedures and a local mean normal prothrombin time.