The Effect of Calibration Method on Repeatability and Reproducibility of Pressure Mat Data in a Canine Population.

ABSTRACT

OBJECTIVE: The aim of this study was to investigate the repeatability and reproducibility of two different pressure-sensitive walkway calibration protocols, while collecting gait data from a heterogenous group of dogs. STUDY DESIGN: Fourteen dogs were walked across a high-definition pressure-sensitive walkway (Tekscan Strideway HRSW3) to obtain five valid trials from each dog. Two different calibration protocols were created following manufacturer recommendations: human step and phantom step using a custom-built three-legged device. Each calibration protocol was repeated five times, by three different operators, and then individually applied to the raw canine gait data. The software then automatically generated values for peak vertical force, vertical impulse and peak pressure for each trial. RESULTS: To control for the different bodyweight of the dogs, forces are reported as a percentage of bodyweight. Values for peak vertical force percentage of bodyweight, vertical impulse percentage of bodyweight and peak pressure were significantly different between calibration protocols, but the results were linearly correlated. Both calibration protocols were highly repeatable and highly reproducible. CONCLUSION: Both the step and phantom calibration protocols individually generated highly repeatable and reproducible results, which were not affected by different operators. A linear correlation was identified which may make it possible to apply a correction factor to enable comparison of results between different studies.