Objective: To test the interchangeability of a previously untested urine reagent strip, Clarity (RAC Medical), with the gold standard, Multistix (Bayer).
Design: Seventy-six urine samples were tested with both the comparator and the gold standard urine reagent strips. Pairs of reagent strips were analyzed in the Clinitek Analyzer, recording the following: leukocytes, nitrite, urobilinogen, protein, pH, blood, specific gravity, ketone, bilirubin, glucose, and color. Data was assessed using statistical comparison of ordinal data (chi-square, Fisher's Exact, kappa, and weighted kappa). This study was approved by the Indiana University-Purdue University at Indianapolis Institutional Review Board.
Setting: The study took place at Wishard Health Services, Indianapolis IN.
Patients or other participants: All urine tested was obtained from patients of the primary care clinic at Wishard Health Services.
Interventions: n/a.
Primary outcome measure: The ability for both reagent strips to generate (statistically significant) identical readings across all 11 measurements for each sample.
Result: Kappa values were deemed the best indicator to consistently examine the reproducibility of all 11 measurements of the Clarity versus the Multistix. Ten of eleven measurements were concluded to be non-reproducible by the Clarity strips; nitrite readings achieved a kappa value above 0.85, whereas all other readings achieved kappa values well below the acceptable limits of this investigation (ranging from 0.00 to 0.65).
Conclusion: There was a lack of statistically significant agreement between the results of both products and therefore it was concluded that both products cannot be used interchangeably.