How to define and document a sampling method for medical devices under MDR

This article outlines the requirements for medical device distributors and importers regarding the establishment and documentation of sampling methods. Compliance with these provisions is essential for fulfilling responsibilities under the Medical Device Regulation (MDR).

#The Role of Distributors and Importers in Device Surveillance

Distributors and importers play a critical role in the medical device supply chain, acting as a link between manufacturers and end-users. Their responsibilities extend beyond merely handling devices to include active vigilance regarding product conformity. Both distributors and importers are obliged to contribute to post-market surveillance activities, as detailed in the MDR.

#Importer Responsibilities

Importers are defined in Article 2(13) MDR as any natural or legal person established within the Union that places a device from a third country on the Union market. Article 13 MDR outlines specific duties for importers. Before placing a device on the market, importers must verify certain aspects. These include ensuring the device is CE marked, that a Declaration of Conformity has been drawn up, and that an EU authorised representative has been designated by the manufacturer. Furthermore, importers must ensure that the device is labelled in accordance with Article 10(11) and Article 27 MDR and that the manufacturer has assigned a UDI. They must also ensure that the manufacturer has complied with the registration requirements set out in Article 29 MDR. One key responsibility, as per Article 13(4) MDR, is to "keep a copy of the EU declaration of conformity and, if applicable, a copy of the relevant certificate, including any amendments and supplements, issued in accordance with Article 53, for the period referred to in Article 10(8)."

Critically, Article 13(3) MDR requires importers to ensure that, while a device is under their responsibility, storage and transport conditions comply with the manufacturer's specified conditions. Article 13(4) MDR states that importers must "verify that the device is registered in EUDAMED" (where applicable, regarding its current status and scope). The importer must inform the manufacturer and the authorised representative, and the competent authority of the Member State in which the importer is established, if they consider that a device does not conform with the MDR (Article 13(6) MDR).

#Distributor Responsibilities

Distributors, defined in Article 2(14) MDR as any natural or legal person in the supply chain, other than the manufacturer or the importer, that makes a device available on the market, also have significant obligations. Article 14 MDR mandates that distributors verify that the device bears the CE marking, that an EU declaration of conformity has been drawn up, and that the device is labelled in accordance with the MDR. They must also ensure that, where applicable, a UDI has been assigned by the manufacturer and that the manufacturer has complied with the registration requirements set out in Article 29 MDR. Distributors must also verify that the importer, where one exists, has complied with its registration requirements (Article 14(2) MDR).

Article 14(3) MDR states that distributors must ensure that, while a device is under their responsibility, storage and transport conditions comply with the manufacturer's specified conditions. Similar to importers, distributors must inform the manufacturer and, where applicable, the importer and the authorised representative, and the competent authority of the Member State in which the distributor is established, if they consider that a device does not conform with the MDR (Article 14(4) MDR).

#The Requirement for Representative Sampling

Both importers and distributors are required to implement procedures for sampling. Article 13(4) MDR for importers and Article 14(2) MDR for distributors state that they "shall verify that the device is CE marked and that an EU declaration of conformity has been drawn up. They shall verify that a UDI has been assigned by the manufacturer, where applicable, and that the manufacturer has complied with the registration requirements set out in Article 29. They shall check that the device is accompanied by the information to be supplied by the manufacturer in accordance with Article 10(11) and that it is in the language required by the Member State in which the device is made available to the user or patient. Importers and distributors shall have a system in place to check, on a representative basis, devices, and shall report non-conforming devices, complaints and recalls to the manufacturer, to the authorised representative and to the importer, where applicable, and to the competent authority of the Member State in which they are established."

This "system in place to check, on a representative basis, devices" is the core requirement for representative sampling. The sampling procedures must be documented within the quality management system of the distributor or importer.

#Defining and Documenting a Sampling Method

To comply with Article 13(4) MDR and Article 14(2) MDR, a robust sampling method is necessary. This method must be clearly defined and documented, ensuring its systematic application and traceability.

#Key Elements of a Sampling Method

1. Scope: Clearly define which devices or batches are subject to sampling. This may include devices arriving from a new manufacturer, devices from certain high-risk categories, or products that have previously been associated with non-conformities.
2. Frequency: Specify how often sampling will occur. This could be per batch, per shipment, or at defined time intervals. The frequency should be justified based on risk, volume, and past performance.
3. Sample Size: Determine the number of units to be sampled from a given batch or shipment. This should be statistically justifiable, considering the batch size and acceptable quality limits. MDCG 2021-27, Questions and Answers on Articles 13 & 14 of the Medical Device Regulation (MDR) 2017/745, provides useful guidance, stating that the sampling plan should be risk-based and take into account factors such as the type of device, its classification, known issues, and the manufacturer’s quality system. It further clarifies that a fixed sample size is not always appropriate and that sampling should not be limited to visual checks.
4. Sampling Criteria: Outline the specific attributes to be checked during the sampling process. This typically includes:
   • Verification of CE marking presence and validity.
   • Confirmation of the EU Declaration of Conformity availability.
   • Checking for the UDI-DI (Unique Device Identification - Device Identifier) on the label and packaging.
   • Inspection of labelling and instructions for use (IFU) for completeness, legibility, and language requirements.
   • Assessment of packaging integrity.
   • Verification of accompanying documentation, such as certificates for sterile products or unique batch numbers.
5. Recording and Reporting: Establish a system for documenting the results of each sample inspection. This includes identifying any non-conformities, initiating corrective actions, and reporting to the manufacturer, authorised representative, and competent authorities as required by Article 13(6) MDR and Article 14(4) MDR.
6. Personnel: Identify the personnel responsible for conducting sampling, their required training, and their competency.
7. Review and Update: Define a regular review process for the sampling method to ensure its continued effectiveness and compliance with evolving regulatory requirements or changes in device characteristics.

#Documentation Requirements

All aspects of the sampling method must be documented. This documentation typically forms part of the distributor's or importer's quality management system (QMS). Key documents include:

• Standard Operating Procedure (SOP): Detailing the step-by-step process for sampling, including criteria, frequency, sample size, and corrective actions.
• Sampling Plan: A specific document outlining the application of the SOP to different device types or categories.
• Records of Inspection: Forms or digital logs to record findings, including batch numbers, dates, personnel, and any observed non-conformities.
• Training Records: Documentation of personnel training in the sampling procedures.

#Example Sampling Criteria

The following table provides an illustrative example of checks that could be included in a sampling plan for an importer or distributor.

#Common mistakes in practice

• Lack of documented procedures: Operating without written SOPs for sampling, leading to inconsistent application.
• Insufficient sample size: Choosing an arbitrary or too small sample size that does not provide a representative overview of the batch.
• Inadequate training: Personnel performing checks lack proper training in identifying non-conformities or understanding MDR requirements.
• Limited scope of checks: Focusing only on visual inspection and neglecting to verify documentation, language requirements, or UDI information.
• Failure to report non-conformities: Not consistently reporting identified issues to the manufacturer, authorised representative, and competent authority as mandated by Article 13(6) MDR and Article 14(4) MDR.
• No linkage to corrective actions: Sampling results are recorded but do not trigger investigations or corrective and preventive actions (CAPA) when non-conformities are found.
• Outdated procedures: Sampling methods are not periodically reviewed and updated to reflect changes in regulations, device types, or supply chain processes.
• Assuming manufacturer compliance: Relying solely on the manufacturer's assurances without performing independent verification checks as required for distributors and importers.
• Ignoring national specifics: Not considering national language requirements for labelling or IFU, which can vary between Member States.

#EUDAMED and Sampling

While EUDAMED does not directly manage sampling procedures, it serves as a central repository for critical device information that influences sampling. Importers and distributors must verify that devices and economic operators are registered in EUDAMED, as specified in Article 13(4) MDR and Article 14(2) MDR. This verification process should be integrated into the sampling method. It is important to note that the EUDAMED modules have been rolled out in stages. Economic operators must confirm the current status and scope of EUDAMED's operational modules with their national competent authority to ensure compliance with the latest requirements. Verification of EUDAMED registration is part of the importer's and distributor's checks. For more details on the platform, refer to the EUDAMED AI platform information at https://eudamedai.com/#kako-deluje.

This material is for information only and is not legal advice. For binding interpretation consult your national competent authority.