Rapid measurement of blood cholesterol: evaluation of a new instrument

Rapid and reliable techniques for the measurement of blood cholesterol are a necessary first step in implementing effective mass screening efforts to reduce the risks of cardiovascular disease. This paper reports preliminary data gathered on the Kodak Ektachem DT60, one of the first of a new generation of dry chemistry analyzers to appear on the market. The results of the first study demonstrated high reproducibility of the methodology (r = .98, p less than .0001) but showed an average 25 mg/dL underestimate of total blood cholesterol as compared with a standardized lipid laboratory. Changes in the manufacturer's calibration protocol in the second study with two other DT60s reduced this bias on serum samples to -18 mg/dL. A third study using fresh blood samples found a difference of 3-11 mg/dL between the two DT60s and the laboratory. A significant difference between the two analyzers was also found. Alternatives are available to enable those who use this instrument to correct for the observed bias. Despite some problems, several other advantages of the technology lend support for its expanded use in public health interventions.