A harmonized, global definition of “medical device” (MD) does not yet exist.
US law and regulations define a medical device as “instrument, apparatus, implement, machine, contrivance, implant, in vitro reagent…intended for use in the diagnosis of disease or other conditions, or in the cure, mitigation, treatment, or prevention of disease, in man or other animals, or Intended to affect the structure or any function of the body…and which does not achieve its primary intended purposes through chemical action …and which is not dependent upon being metabolized for the achievement of its primary intended purposes…”
EU law and regulations define a medical device as any “instrument, apparatus, appliance, software, material or other article… for the purpose of diagnosis, prevention, monitoring, treatment or alleviation of disease,…injury or handicap, investigation, replacement or modification of the anatomy or of a physiological process, control of conception, and which does not achieve its principal intended action in or on the human body by pharmacological, immunological or metabolic means…”
The different heath authorities have rules for determining the risk class of a medical device, based on its potential for harm if misused, design complexity, and use characteristics. Risk classifications generally range from Class I through Class III or IV, where Class I is the lowest level of risk. Risk classification has an impact on the regulatory pathway to be followed for product registration applications and may also influence the quantity and quality of documentation required to support the applications in each target market.