Inhalation adherence monitoring using smart electonic add-on device: Accuracy evalutaion using simulated real-life test program

We present an evaluation of the accuracy of an adherence monitoring add-on device (SmartTurbo v2.0, Nexus6 Limited, Auckland, New Zealand) designed to fit a commercial inhalation device (Turbuhaler®, dry powder inhaler, AstraZeneca). The evaluation has been based on simulated real-life placebo usage by 11 patients and carried out during a 12 day period. The simulated usage covered low and high inhalation patterns. Of the simulated total 2089 inhalation events 2073 were correctly detected and recorded on the devices' memory. The above indicated an overall accuracy of detection of 99.2%, including possible human errors from the testers. The results confirm that the tested add-on device could successfully be utilized in clinical trials as a reliable replacement of a patient diary report.