Determination of disk diffusion susceptibility testing interpretive criteria using model-based analysis: development and implementation

- dBETS is a free online software package developed to determine zone breakpoints
- The error-rate bounded (ERB) method is often used to determine zone breakpoints
- Model-based methods, however, have been shown superior in precision and accuracy
- dBETS provides visualization tools along with the ERB and model-based approaches
- We demonstrate the performance of dBETS using four publicly available CLSI data sets

The determination of diffusion test breakpoints has become a challenging issue due to the increasing resistance of microorganisms to antibiotics. Currently, the most commonly-used method for determining these breakpoints is the modified error-rate bounded method. Its use has remained widespread despite the introduction of several model-based methods that have been shown superior in terms of precision and accuracy. However, the computational complexities associated with these new approaches has been a significant barrier for clinicians. To remedy this, we developed and examine the utility of a free online software package designed for the determination of diffusion test breakpoints: dBETS (diffusion Breakpoint Estimation Testing Software). This software package allows clinicians to easily analyze data from susceptibility experiments through visualization, error-rate bounded, and model-based approaches. We analyze four publicly available data sets from the Clinical and Laboratory Standards Institute using dBETS.