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by Paul Brooks

In 1993, the European Union introduced the Medical Devices Directive 93/42/EEC. At that time and during the transition period, compliance to the directive was voluntary. By the summer of 1998, however, the MDD had become the basis of mandatory regulatory requirements for all medical device manufacturers selling their products in the European Union.

Today, CE marking is required on all products that fall within the scope of any of the European Union's New Approach Directives (For additional information about these, including a complete list of the current directives, see the July 2002 Quality Digest article, "The Global Marketplace and CE Marking"). The directives cover a vast array of products from various industries--including telecommunications equipment, machinery and toys--in addition to medical devices.

This summer, the European Medical Devices Expert Group published the first major report and analysis of the MDD. This article summarizes the key points raised in the report.

The MDD provides an appropriate legal framework for regulating medical devices, but some aspects of it require further improvement and/or implementation, according to the MDEG report. In particular, attention must be given to how Notified Bodies are designated and monitored, how conformity assessments are conducted, the classification of some devices, and how provisions concerning clinical data and quality assurance are implemented.

The report recognizes the complexity and pace of development in the medical devices sector and the importance of maintaining efficient and effective regulations. These ensure that Europeans benefit from the safest, most current technologies. Acknowledging, too, that different regulatory approaches are required for different industries, the report specifically discusses the differences between the medical devices and pharmaceutical industries.

The report also comments upon the growing global recognition of Europe's CE marking approach to regulating medical devices. Other regulatory agencies are actively considering or even adopting this approach as the basis of their own regulations. It also provides significant inspiration for the work undertaken by the Global Harmonization Task Force.

The report identifies the following main areas of concern:

Classification of medical devices

Conformity assessment

Notified Bodies

Clinical evaluation and post-market surveillance

Classification of medical devices

Unlike some regulatory systems in which devices are officially listed and classified by the regulator, under the MDD, the manufacturer applies 18 rules to determine the classification of its own product. Any medical device can be classified by following the logical model provided by the rules, which take into consideration a product's duration of use, degree of invasiveness, power source and contact with patients' bodies. A number of special rules cover anomalies and supplement the rules. Inevitably, a very small number of devices raises differences in interpretation among manufacturers, Notified Bodies and competent authorities. The MEDDEV Guidance Document published by the MDEG provides clarification on interpreting the rules and includes examples of devices the rules are intended to cover. (Copies of the MEDDEV Guidance Document are available from www.bsiamericas.com/medicaldevices .)

The report identifies three problems with the current classification of devices:

The need to upgrade or downgrade some devices' classification. The report suggests some devices do not achieve appropriate classification using the current rules. Because a classification affects the conformity assessment conducted by a Notified Body, some devices might not be subject to a sufficiently vigorous review in relation to their perceived inherent risks. The report proposes that several devices be reclassified. These include breast implants (upgraded from Class IIb to Class III, already agreed); stents, hip implants, intraocular lenses, ventricular assist devices, portable infusion pumps (all up to Class III); disinfectants (up to Class IIb); and nursing beds, wheelchairs and patient lifters (up to class IIa). The report mentions that some devices could be downgraded, although no current examples are cited.

Anomalies in the classification rules. The report indicates that a limited number of anomalies occurs because of the classification rules. For example, reusable surgical instruments are Class I devices according to the MDD rules, whereas single-use instruments are Class IIa, despite the fact that reusable devices may be of higher potential risk than single-use devices.

Incoherence in the classification rules. The report identifies incoherence between rules six and seven of the MDD. Rule six classifies devices that come into contact with the central nervous system on a transient basis (i.e., fewer than 60 minutes) as Class IIa and devices that are in contact for a short term (i.e., up to 30 days) as Class III. The report contends that risks don't diminish with the reduced duration. Therefore, all such devices should be classed in the highest-risk category and marked as Class III.

The report concludes that the existing mechanism under the directive's clause 13 would address classification issues. This clause allows the European Commission to consider substantiated classification cases presented by member states and take appropriate action. In doing so, no amendment to the MDD would be required.

Conformity assessment

One of the conformity assessment routes available under the MDD is full quality assurance (Annex II). The report outlines concerns about Notified Bodies adequately evaluating the designs of high-risk medical devices during Annex II assessments, particularly with regard to some Class IIb devices. The report also suggests reclassifying those devices that are of most serious concern up to Class III, which would require a design dossier submission to the Notified Body. Irrespective of the class devices (IIa to III) on an Annex II quality system audit, the Notified Body is required to include product expertise on the audit and effectively sample and assess technical documentation, including risk analysis, clinical data and design evaluation. A chosen sample must reflect the risks associated with the device's intended use, the complexity of manufacturing technologies and the range of devices produced. The report indicates that this area of conformity assessment needs further clarification guidance for Notified Bodies.

The report also queries the certification validity of devices covered by conformity assessment annexes in which no expiration date is required. In these cases, the manufacturer's responsibility to design and construct devices meets the generally acknowledged term "state of the art." The report suggests that an effectively running system can still go "off the rails" in three years. Notified Bodies should have the opportunity to re-examine certain products' designs and classifications, and the report contends that expiration dates can assist them in this context.

The report states that manufacturers and Notified Bodies should continually monitor devices' conformity with the current "state of the art." However, further discussion is needed to adequately define the term as well as its consequential effect on certification validity.

Notified Bodies

The Notified Bodies are critical elements to successful implementation of the MDD. To ensure their systems are effective requires consistent action by both the Notified Bodies themselves and competent authorities. Today there are more than 60 Notified Bodies designated under the MDD. Questions exist regarding the competency, coherency in interpretation and transparency of their work and decisions.

Competent authorities and manufacturers have questioned the ability of Notified Bodies to conduct conformity assessments in all the designated product areas. Incompetence is unsatisfactory not only from a regulatory perspective, but also because it undermines the value of a robust conformity assessment that might identify problems before they occur. The report states that competent authorities should more carefully designate and monitor Notified Bodies and allow them to specialize in the areas for which they're designated. This would make them more effective.

Also important is ensuring coherent interpretation among Notified Bodies. Many recognize that the Notified Body-initiated NB-MED Group has achieved much progress. The group drafts and publishes Notified Body recommendations and consensus statements, which provide a basis for consensus interpretation and agreement about the MDD requirements. All Notified Bodies are entitled to participate in the NB-MED Group, and most do. However, some critics maintain that the NB-MED Group documents aren't readily available and that not all Notified Bodies follow the recommendations. (A complete set of recommendations is available at www.bsiamericas.com/MedicalDevices/GuidanceDocs/NBRecommendations.xalter .)

The transparency of Notified Bodies' certification decisions is another area of concern. The report suggests that they be required to make more information available about their decisions. The Notified Body Operations Group, created in 2000, addresses and considers all concerns regarding Notified Bodies. This group includes representatives from member states and the European Commission.

Clinical evaluation

The MDD requires that all devices, irrespective of classification, include adequate clinical data concerning their characteristics and performance under normal use as well as an evaluation of any undesirable side effects. This data can be a compilation of relevant scientific literature along with a critical evaluation of the findings, or the results of a clinical investigation (i.e., trial) that's included in the technical documentation compiled by the manufacturer.

Experience has shown that there's a complete lack of clinical data included in technical documentation for some lower-class devices, which raises serious concerns regarding manufacturers' claims of compliance with the directive. The report suggests that these failings are due to misinterpreting the MDD rather than from shortcomings in the regulatory framework or ambiguity in the text.

The Clinical Evaluation Task Force, an expert working group comprised of representatives from member states, Notified Bodies and relevant industries, is reviewing the subject of clinical data and will publish detailed guidance on issues related to it.

Post-market surveillance

The MDD includes a requirement for post-production surveillance of all classes of devices. One part of this requirement concerns vigilance--i.e., reporting incidents and recalls--which is mostly a reactive activity. The proactive part is post-market surveillance. This requirement, which hasn't always received appropriate attention from manufacturers or Notified Bodies, means manufacturers must document an appropriate system for gaining and reviewing experience in the post-production phase for the range of devices manufactured. The New Approach Directives suggest manufacturers should proactively evaluate actual device experience rather than relying on purely reactive activity such as customer complaints or operating problems.

The report recommends that better guidance be developed for post-market surveillance and that Notified Bodies follow through with it.

The next step

Other issues considered in the report include vigilance, the safeguard clause, confidentiality, market surveillance, the European database and consultations with pharmaceutical authorities. However, the most critical area identified as requiring improvement is conformity assessment. The report states, "Failure to act on one of these elements in the field of conformity assessment will not produce the required improvements." Further work by the NBOG and CETF will provide additional guidance to benefit manufacturers, Notified Bodies and, ultimately, patients and end-users.

Currently, the report isn't binding on the European Commission. However, the policy conclusions drawn from it might be presented to the European Council and European Parliament for consideration.

All in all, the prognosis is that, despite the areas under consideration for improvement, the new approach CE marking system works well to regulate medical devices.

The full MDEG report is available to download at www.bsiamericas.com/MedicalDevices/GuidanceDocs/OtherDocs.xalter

About the author

Paul Brooks, an expert on CE marking under the Medical Devices Directive, is the head of BSI's Medical Devices Group, a Notified Body. He joined BSI in 1981 and has been working with the company's U.S. subsidiary, BSI Inc., since 1993. Today, he's responsible for BSI's Conformity Assessment Body and IVD Notified Body activities. Letters to the editor regarding this article should be e-mailed to letters@qualitydigest.com.