Ray, As Nick says, it very much depends upon your perspective/reasons for needing to narrow the MDD definition. If, as I suspect, you are seeking to define from a Medical devices policy point of view (Controls Assurance et al), then a point worth considering; there are many 'devices' which are not powered electrically, but are nonetheless involved in the clinical treatment/diagnosis of patient condition. Devices such as pneumatic ventilators, surgical tools (shavers, drills etc),aneroid BP are useful examples of where a Trust would have responsibility for identifying/quantifying risk, training and maintenance requirements, and which may or may not involve our good selves.
I like Nick's definition, and would suggest a slight modification to cater for the above argument;
Any device that is used in the Analysis, Diagnosis, Treatment and Therapy, and the Monitoring, of a patient's clinical condition, and which has a maintenance and/or calibration requirement to give assurance of continued performance.
