A multicenter nationwide reference intervals study for common biochemical analytes in Turkey using Abbott analyzers.

BACKGROUND: A nationwide multicenter study was organized to establish reference intervals (RIs) in the Turkish population for 25 commonly tested biochemical analytes and to explore sources of variation in reference values, including regionality. METHODS: Blood samples were collected nationwide in 28 laboratories from the seven regions (≥400 samples/region, 3066 in all). The sera were collectively analyzed in Uludag University in Bursa using Abbott reagents and analyzer. Reference materials were used for standardization of test results. After secondary exclusion using the latent abnormal values exclusion method, RIs were derived by a parametric method employing the modified Box-Cox formula and compared with the RIs by the non-parametric method. Three-level nested ANOVA was used to evaluate variations among sexes, ages and regions. Associations between test results and age, body mass index (BMI) and region were determined by multiple regression analysis (MRA). RESULTS: By ANOVA, differences of reference values among seven regions were significant in none of the 25 analytes. Significant sex-related and age-related differences were observed for 10 and seven analytes, respectively. MRA revealed BMI-related changes in results for uric acid, glucose, triglycerides, high-density lipoprotein (HDL)-cholesterol, alanine aminotransferase, and γ-glutamyltransferase. Their RIs were thus derived by applying stricter criteria excluding individuals with BMI >28 kg/m2. Ranges of RIs by non-parametric method were wider than those by parametric method especially for those analytes affected by BMI. CONCLUSIONS: With the lack of regional differences and the well-standardized status of test results, the RIs derived from this nationwide study can be used for the entire Turkish population.

New generation IQ-200 automated urine microscopy analyzer compared with KOVA cell chamber.

OBJECTIVE: The examination of the urine remains to be one of the most commonly performed tests in laboratory practice. Currently, laboratories also need to accredit their urine diagnostics by comparing their measurement methods to acceptable references. In this study we compared particle counts obtained by new generation automated technique, image capture analysis (IQ-200) with those of a standardized chamber counts. DESIGN AND METHODS: The same 258 urine samples from different departments of a hospital assayed by IQ-200 were analyzed in parallel with the KOVA cell chamber system. Clinically significant discrepancy results (positive vs. negative) for red blood cell (RBC) and white blood cell (WBC) were also compared with those obtained by dipstick testing. RESULTS: There was a good agreement between the automated system and sediment microscopy for RBCs, WBCs, and squamous epithelial cells (SCs) (r=0.90; r=0.80; r=0.72, respectively: P<0.001). The IQ-200 was more sensitive for determining RBCs, WBCs, and SCs than other formed elements. CONCLUSIONS: IQ-200 can perform accurate quantification of microscopic element in urine. However, automated techniques are not completely free of error. Therefore, by adopting an appropriate algorithm and combining the results with stript analysis and other laboratory tests allows further reduction of clinically important errors.