Assessment of Two Blood-Analyzer Systems Intended for Diagnostic Testing in the Physician's Office

Abstract

Abstract We have assessed the Bio-Dynamics "Unitest System" and the Dow Chemical "Diagnostest." Day-to-day reproducibility and within-day precision of the Unitest uric acid and urea nitrogen kits were beyond acceptable limits of error. For Diagnostest, day-to-day reproducibility of bilirubin was outside these limits for two concentrations of bilirubin, one each for uric acid and cholesterol. The Unitest kit gave falsely high readings for cholesterol such that incorrect diagnoses could result. The Diagnostest cholesterol procedure gave values significantly lower than those obtained with the AutoAnalyzer. With Unitest, low results were found on specimens with supranormal uric acid; with Diagnostest low results were obtained for supranormal concentrations of urea nitrogen. Both systems yielded acceptable results for glucose and hemoglobin. We conclude that personnel not technically trained could not obtain reliable data with these systems.