in order to assess its utility for the improvement of efficiency of routine immuno-chemistry workstation. METHODS: Within- and between-day precision, linearity, and recovery rates were evaluated for 21 items (T3, T4, TSH, E2, LH, Testosterone, FSH, prolactin, AFP, CEA, CA125, CA19-9, total PSA, CRP, ASO, RF, Ig G, Ig M, Ig A, C3C, and C4). Commercialized controls(Roche Diagnostics, Basel, Switzerland) and patient sera for test specimens were used. Centaur(Bayer Diagnostic Division, New York, USA) and LX 2200(Eiken Chemical Co., Tokyo, Japan) were used as the control analyzers to evaluate the correlation. RESULTS: Within-day Coefficients of variation(CVs) was below 5% for all the analytes and between-day CVs was below 5.0% except ASO(8.01%). The linearity was excellent(r2>0.999; slope, 0.98-1.02; p<0.001). Recovery rates for all analytes were in the range of 95% to 103%. The correlation coefficients between modular and Centaur was exceeded 0.971, and between modular

and LX2200 exceeded 0.910, except RF(r=0.834). (P<0.05) CONCLUSION: The recently developed Modular Analytics proved to be highly precise and linear for quantitative analysis of hormones, tumor markers, and serum proteins in routine immuno-chemistry workstation. Correlations with Centaur and LX 2200 were thought to be good.