Verification of Reliability of Automated Urine Test Strip Colorimetric Program Using Colorimetric Analysis: Quasi-Experimental Study (Preprint)

Abstract

Background: Visual judgment is susceptible to human errors, such as evaluation item errors and judgment time variations. Automated Urine Test Strip Colorimetric testing may be used by practitioners and small-scale medical check-up facilities to test urine samples.

Objective: We develop an automated urine test strip colorimetric program using images taken with a smartphone camera to judge the color of the urinalysis test strips objectively.

Methods: To verify the program's reliability, we compare urine samples from real patients with the results of an automated urine analyzer.

Results: The concordance rate with the automated urine analyzer is 78.6% on average for 12 items. The concordance rate for the ±1 rank test is 95.4%. In addition, determining urinary albumin level results in a sensitivity of 100% and specificity of 58.6%. The area under the curve derived from the ROC curve is 0.907.

Conclusions: The results clarified that colorimetric analysis in a fixed imaging environment could be used to determine urine test strips without calibration. This method may be used to screen for microalbuminuria, helping prevent exacerbation of diabetic nephropathy.