Table 1.

Summary of differences between risk classes.

Class	Documentation	Notified body involved?	QMSa	Certificates	Clinical investigation
I (low risk)	Manufacturer must compile the technical documentation and self-declare conformity	No	Yes	No	Not mandatory. May be required depending on the outcome of the clinical evaluation
IIa (low-medium risk)	Manufacturer must draw up the technical documentation and apply to a European Notified Body	Yes	Yes, certified	Yes (Annex IX certificate, QMS certificate)	Not mandatory. May be required depending on the outcome of the clinical evaluation
IIb (medium-high risk)	Manufacturer must draw up the technical documentation and apply to a European Notified Body	Yes	Yes, certified	Yes (Annex IX certificate, QMS certificate)	Not mandatory. May be required depending on the outcome of the clinical evaluation
III (high risk)	Manufacturer must draw up the technical documentation and apply to a European Notified Body	Yes, expert panel	Yes, certified	Yes (Annex IX certificate, QMS certificate)	Mandatory

^aQMS: Quality Management System.