MULTICENTER EVALUATION OF THE BOEHRINGER-MANNHEIM HITACHI-911 ANALYSIS SYSTEM

The analytical performance and practicability of the Boehringer Mannhe im (BM)/Hitachi 911 analysis system have been assessed in a multicentr e evaluation, which involved six laboratories from European countries. Analytes commonly used in classical clinical chemistry were tested in a core programme, which mainly followed the ECCLS guidelines. In addi tion, a satellite programme covered other analytes, such as proteins, drugs and urine analytes. In total, the study comprised more than 1000 00 data items collected over a three-month period. The evaluation was supported with 'Computer Aided Evaluation' (CAEv) and telecommunicatio ns. Acceptance criteria for the results were established at the beginn ing of the study. Nearly all of the analytes met the imprecision limit s: within-run imprecision (as CVs) was 2% for enzyme and substrate ass ays, 1% for ISE methods and 5% for immunoassays; between-day imprecisi on was 3% for, enzyme and substrate assays, 2% for ISE methods and 10% for immunoassays. No relevant drift effects (systematic deviation gre ater than or equal to 3%) were observed over eight hours. The methods were lineal over a wide range. Sample-related and reagent-dependent ca rry-over can be reduced to a negligible amount by integration of a sof tware-controlled wash-step. Endogenous interferences were found for cr eatinine (Jaffe method) and uric acid assays (caused by bilirubin), fo r creatine kinase, creatine kinase MB isoform and gamma-glutamultransf erase (caused by haemoglobin), and for immunoglobulin A (caused by lip aemia). Accuracy was checked by an interlaboratory survey, recovery st udies in control materials and method comparison studies. The survey s howed that, with the exception of cholesterol and iron in two laborato ries, the recovery of analytes did not deviate by more than 5%. Sixty- six of the 77 method comparisons performed met the acceptance criteria . The deviations of the remaining 11 results could be explained by dif ferences in either calibration, application or 69 the use of differ en t methods. Practicability was assessed using a questionnaire which cov ered all of the important aspects of an analysis system in the clinica l laboratory. Twelve groups of attributes out of 14 were rater higher for the BM/Hitachi 911 than for the present situation in the laborator ies concerned. Especially high scores were given for the versatility g roup. The acceptance criteria for the analytical performance of the BM /Hitachi 911 analysis system were fulfilled in all laboratory segments with few exceptions. The practicability exceeded the requirements in most of the attributes. The results of the study confirmed the usefuln ess of the system as a consolidated workstation in small- to medium-si zed clinical laboratories and in STAT laboratories, or as an instrumen t for special analytes like proteins and drugs, or for urinalysis in l arge laboratories.