Analytical performance of the random access analyser Hitachi 737. A multicentre evaluation

The selective multitest analyser Hitachi 737 was examined according to the ECCLS guidelines in a multicentre evaluation involving 4 laboratories. Twenty routine parameters, including the electrolytes, sodium, potassium and chloride, were measured at 37 degrees C. All of the measured values were included for evaluation without correcting for outliers. The trial, which lasted 4 months and involved over 70 000 analyses, basically yielded the following results: The precision can be termed very good. For the majority of the methods, the day-to-day coefficients of variation were below 2%. The highest coefficient of variation was 6.3% (for creatine kinase) and the lowest below 0.1% (for gamma-glutamyltransferase). The recovery of the assigned values of control sera was very good for most of the parameters (between 95% and 105%). Only with bilirubin, phosphate and chloride did greater deviations occur in a few control sera. Excellent agreement was found between the results obtained from the instruments used in the comparison: the Hitachi 705, a flame photometer and a chloride meter. No drift effects were observed. The same applied to carryover effects, provided that Boehringer Mannheim's recommendations concerning method combinations are observed. Because of the large measuring range, it is necessary to repeat analyses only in exceptional cases. During the entire period of the trial there were no stoppages due to the instrument malfunction. As a result of its reliability, the Hitachi 737 is well suited for routine operation and emergency analysis in medium to large-sized laboratories.