Verification of UriSed 3 PRO automated urine microscope in regional laboratory environment

•UriSed 3 PRO automated microscope was successfully verified for nine laboratories.•Uncertainties were estimated for imprecision and comparisons of low particle counts.•New autoverification rules managed 70–75% of samples using 10 instruments. Ten UriSed 3 PRO automated microscopes (77 Elektronika, Hungary) were verified for nine HUSLAB laboratories with 160 000 annual urine samples. Particle counting of the primary UriSed 3 PRO instrument (77 Elektronika, Hungary) was verified against reference visual microscopy with 463 urine specimens, and against urine culture on chromogenic agar plates with parallel 396 specimens. Nine secondary instruments were compared pairwise with the primary instrument. Relative imprecisions compared to Poisson distribution, R(CV), were estimated to be 1.0 for white blood cell (WBC) and 1.5 for red blood cell (RBC) counts, respectively. Spearman’s correlations against visual microscopy were rS = 0.94 for WBC, rS = 0.87 for RBC, and rS = 0.82 for squamous epithelial cell (SEC) counts. Agreement with visual microscopy (Cohen’s weighted kappa) was 0.94 for WBC, 0.89 for RBC, 0.88 for SEC, 0.59 for combined casts, and 0.49 for non-squamous epithelial cells (NEC). Bacteria were detected with a sensitivity of 90% and specificity of 39 against culture at 107 CFB/L (104 CFU/mL). Created flagging limits allowed automated reporting for 70–75% of patient results. UriSed 3 PRO instruments were adopted into routine use after acceptance of the verification.