Oct 5, 2009

Directive 2007/47/EC becomes effective March 21, 2010 and will require Notified Bodies to review a sample of Technical Files for Class IIa and Class IIb devices. The most frequent question from companies with numerous devices has been: What is an appropriate sample?

While manufacturers should receive notice directly from their Notified Body, we wanted to outline the guidance issued by the Notified Body Operations Group (NBOG) to Notified Bodies in July of 2009. The Guidance on Notified Body’s Tasks of Technical Documentation Assessment on a Representative Basis addresses how Notified Bodies evaluate technical documents of Class IIa and IIb devices according to Directive 2007/47/EC. Further, it provides guidance on sampling selection and depth of assessment.

Notified Bodies are to review at least one representative sample of Class IIa devices from each device subcategory, and similarly, at least one representative sample from each generic Class IIb device group for compliance to Directive 2007/47/EC. The terms “device subcategory” and “generic device group” are defined by the new directive as well.

For large groups of Class IIa devices, NBOG recommends a sample to be taken from each set of scope expressions; these specific terms are defined by NBOG BPG 2009-3.

For a large group of class IIb devices, however, NBOG proposes the following procedure:

  • Up to 2 groups: a sample from each group
  • Up to 10 groups: a sample from 3 of these groups
  • Up to 20 groups: a sample from 5 of these groups
  • Up to 30 groups: from 7 groups a sample N
  • More than 30 groups: from N/10 + 5 groups a sample

While sampling selection is important in the depth and extent of the assessment, the device classification, novelty of technology, complexity of design, and level of intervention are all factors that will be considered. Further, the sterilization methods, and results of any similar assessments that have already been carried out according to Directive 2007/47/EC will also be used to determine sample selection and size.

The notified bodies have been instructed to document their justification process in determining the sampling lest they are asked to provide their reasoning to the appropriate competent authority. NBOG instructs that at a minimum, the documents that ought to be reviewed in the assessment include:

  • intended use and confirmation of the correct medical device classification
  • essential requirements checklist
  • risk management
  • pre-clinical data
  • clinical evaluation
  • information supplied by the manufacturer including labeling and instructions for use
  • declaration of conformity
  • any technical documentation related to risk

For any new devices, either Class IIa or IIb, NBOG stipulates that manufacturers must inform their Notified Body so that a review is conducted before the device is marketed for sale.

For more information, please consult the original content of the NBOG Guidelines. The NBOG guidance provides clarification on the new requirements for Class IIa and IIb devices and gives insight as to what a Notified Body might expect. Medical device manufacturers need to be educated about these new requirements before the March 21, 2010 effective date.


  • Stewart Eisenhart