Selecting a bedside glucose monitor for outpatient clinics.

The purpose of this study was to determine the accuracy of two bedside capillary blood glucose monitors that were being considered for purchase for an adult outpatient clinic. Participants were 101 patients 18 years or older with a diagnosis of diabetes mellitus who were attending medical service outpatient clinics. Participants were randomly assigned to two groups for bedside glucose measurement. Clinic nurses trained for the study did the bedside glucose readings and all venous blood samples were analyzed in the hospital's clinical laboratory. Results of t tests indicate a statistically significant difference between the bedside capillary and venous glucose levels for the total sample (p < or = 0.001). The difference between bedside capillary glucose and venous glucose within monitor groups for bedside capillary glucose and venous glucose was also statistically significant (p < or = 0.001) for both groups. The mean percentage difference between the venous (reference) readings and bedside capillary glucose reading was 8.3% for the Accu-Easy and 12.4% for the Glucometer Encore. This between-monitor group percentage difference was statistically significant (p < or = 0.001). Regression equations generated from patient data then used to predict venous glucose values from bedside capillary glucose values indicate variability in the accuracy of the monitors, especially in the higher ranges, which could result in undertreatment of hyperglycemia.