For clinical applicability the device should be able to distinguish hypoglycaemia-induced EEG changes from noise, artefacts and physiological variations in the EEG including the low-frequency waves seen during sleep, with high sensitivity and specificity using a mathematical algorithm that classifies the EEG in real-time. There should be a "time-window" between hypoglycaemia-induced EEG changes and severe cognitive impairment. The device should be fully compatible with normal everyday activities. Thus, the device should be small, fully biocompatible and implantable, and the monitoring and processing unit should be small and have sufficient battery power.