Aims To evaluate the screening test ability of UF-1000i combination with AX-4280 for major pathological urinary formed elements and to establish screening rules suitable for our laboratory.

Methods A total of 2220 cases of urine samples were collected from out-patients and inpatients. The sample tests were finished within 4 h after collection. The results were verified and corroborated with microscopic tests.

Results In ‘both-negative’ group, the negative predictive values for red blood cell, white blood cell and cast were 99.12%, 99.56% and 100%, respectively, and the false negative rates were 0.87%, 0.44% and 0%, respectively. In ‘both-positive’ group, the positive predictive values for red blood cell, white blood cell and cast were 69.18%, 74.41% and 33.33%, respectively, and the false positive rates were 30.82%, 25.59% and 66.67%, respectively. In ‘U positive/A negative’ group, the positive predictive values for red blood cell, white blood cell and cast were 32.47%, 23.67% and 8.57%, respectively, and the false positive rates were 67.53%, 76.36% and 91.43%, respectively. In ‘U negative/A positive’ group, the positive predictive values for red blood cell, white blood cell and cast were 8.18%, 19.50% and 4.67%, respectively, and the false positive rates were 91.82%, 50.50% and 95.24%, respectively.

Conclusions When the results of the red blood cell, white blood cell and cast tested by UF-1000i were all negative, and the results of the red blood cell, white blood cell and protein tested by AX-4280 were negative, an automatic report stating ‘normal microscopic appearance’ was generated, and then the microscopic test rate was reduced by 37.6%. However, if any automated parameter measurement was out of the reference range, corroboration by manual microscopy was advisable.