Inter-laboratory evaluation of the COBAS INTEGRA (R) 400 analytical system

COBAS INTEGRA 400 is a random-access analytical system consolidating assays for clinical chemistry analytes, electrolytes, serum proteins, drugs of ab use and therapeutic drugs. Analytical performance and practicability of the instrument were evaluated in seven laboratories over a 2-year period in pa rallel with system development. Good within-run and total imprecision for a ll assays was observed with a few exceptions for specimen pools with low co ncentration or activity. The coefficients of variation for total imprecisio n were well below 3.0% for clinical chemistry analytes and electrolytes, an d below 5.0% for serum proteins and therapeutic drugs. Method comparisons d emonstrated a good agreement with the various systems used for comparison, with slopes varying typically from 0.94 to 1.05, and Spearman correlation c oefficient generally > 0.975. Accuracy was verified by recovery of controls and certified reference materials within 90 to 110% of target values. Assa y ranges were linear within +/- 5%. No carry-over on reagent or sample pipe tting systems was observed. Manufacturer-specified interference limits and onboard stabilities of reagents were confirmed. A time study for calculating direct personnel times and total processing ti me was carried out in three laboratories under different conditions includi ng consolidated, STAT and dedicated use. On a scenario-independent basis, t he total working time was shorter on the COBAS INTEGRA 400 than on routine systems in all three laboratories. Personnel time, in particular, was signi ficantly reduced when compared to routine instruments. In general, system p racticability was judged very positively in all laboratories. Owing to its versatility, the instrument is best placed as a consolidated w orkstation in small- to medium-sized laboratories or as an instrument for s pecial determinations such as serum proteins, drugs, urinalysis or emergenc y analyses in large laboratories.