Reproducibility of a semiquantitative method to assess cutaneous cytology.

BACKGROUND: Cutaneous cytology is used in veterinary dermatology to assess bacteria and yeast on the skin surface and in the ears for diagnostic purposes and to monitor treatment success. A number of methods were used in reported studies to quantify micro-organisms on cytology, but evaluation of the intra- and interobserver reliability of the methods is rare. OBJECTIVE: The aim of this study was to evaluate the intra- and interobserver reliability of a semiquantitative cytology assessment method frequently used in practice. METHODS: A total of 60 experienced and inexperienced veterinarians and veterinary students were asked to evaluate 10 glass slides and 18 photographs of cutaneous cytology twice. Cocci, rods, yeast, neutrophilic and eosinophilic granulocytes and macrophages were graded from 0 to 4+. RESULTS: The intra-observer reproducibility for evaluating the slides in the experienced group was 84.3%; in the inexperienced group it was 82.6%. For the photographs, the intra-observer reproducibility was 92.1% in both groups. The interobserver reproducibility for evaluating the slides was 81.6 and 81.0% in the experienced and inexperienced group, respectively; corresponding values for the photographs were 91.0 and 90.0%. There was no significant difference between different participants or between the first and second evaluation by each participant for any of the parameters graded. CONCLUSION AND CLINICAL IMPORTANCE: Based on these results, this semiquantitative method of grading can be recommended for evaluating and monitoring of antimicrobial therapy in daily practice.