Conducting human factors and usability studies is crucial for ensuring the safety and effectiveness of medical devices. When it comes to bringing a medical device to the Chinese market, navigating regulatory guidelines for the application of human factors and usability engineering has become an increasingly important topic since the National Medical Products Administration (NMPA) finalized its guidance on the same. Korey Johnson sat down with Maffee Wan from XplusX (China) and Wolfgang Waxenberger from uintent (Germany) to collectively address some common questions and concerns raised by clients regarding human factors research in China and the recently released NMPA guidelines. We also discussed how these guidelines differ from similar US and European studies.
Understanding the regulatory landscape
Client question: What is your interpretation of the NMPA’s new guidance?
Response: The NMPA draft guidance came out about four years ago, and while there were some notable differences between NMPA and FDA guidance, the two regulatory bodies were largely aligned in their recommendations. The recent finalization of the NMPA guidance has brought them into even closer alignment with the FDA. The NMPA guidance is effective as of October 8, 2024, so now is the time for manufacturers bringing devices to market in China to start planning their human factors approach.
From our viewpoint, executing human factors studies in China can be important in many cases. Our international clients with offices in China have been following practices similar to those in the guidance for a long time, especially for high-risk devices. This approach aligns with both FDA and Chinese rules. In fact, the NMPA’s approach to creating a list of highest priority devices for human factors review parallels the approach the FDA took in 2016 with a similar draft list of priority devices.
If the NMPA follows the FDA’s approach with its list, it means that just because a device isn’t on the list, it doesn’t automatically mean you don’t need to conduct a human factors validation study to show it’s safe and effective to use. Still, these lists can, to some extent, help a manufacturer determine how likely it is that the FDA will require a validation study based on use-related risk.
Key differences between China and other markets
Client question: How does a validation study in China differ from one in the US or Europe?
Response: When execution of a validation study is deemed appropriate, the conduct of the study in China looks largely the same as conducting a validation study in the US or the EU. While the draft NMPA guidance recommended a minimum of 20 representative users in each unique user group, the finalized guidance now aligns with the US recommended minimum of 15 per user group. The approach and methods recommended in the NMPA guidance also seem to align with those recommended by the FDA and in ISO/IEC 62366-1.
One notable difference in the NMPA guidance is related to determining whether a validation study is necessary. In its guidance, the NMPA stipulates that a manufacturer may present a rationale for why a validation study in China is unnecessary if a device is already on the market in the US or Europe and has not undergone any design changes. This is possible in the US, but this pathway is not clearly articulated in FDA guidance and requires inferences across multiple guidance documents.
Many clients ask whether it is mandatory to test on Chinese soil to get approval in China or if, like in Japan, evidence from a foreign study that meets or exceeds local standards can be accepted. The NMPA guidance does state that local testing can be avoided if a product with usability data from another region is already on the market. In practice, of course, whether this is a viable pathway for a human factors submission in China will depend on the specifics of the device in question, its risk level, and the available human factors data.
We advise clients to perform a comparative analysis to assess whether or not there are meaningful changes to the composition of intended users, the use environments, or the product itself. Translate the language in the labeling, and if nothing else changes, show side-by-side translations and justify that there are no workflow or relevant cultural differences between Chinese users and others.
More specifically, the NMPA guidance calls for the following, depending on the level of risk associated with a particular medical device:
High-risk medical devices: Conduct a comparative analysis of the production equivalent product to be brought to market in China against a reference product already on the market elsewhere.
- If the use-related risk associated with any identified differences between products, labeling, users, use environments, or tasks is deemed acceptable, submit the results of this analysis along with an analysis of known use problems for similar products and any available post-market usability data for the reference product.
- If the use-related risk associated with identified differences is unacceptable, modify the product and reconduct the analysis to show all unacceptable use-related risks have been eliminated.
- If it is not possible to modify the product without introducing novel or unacceptable use-related risk, then summative usability testing must be conducted to validate safe and effective use.
Medium and low-risk devices: Conduct an analysis of known use problems and submit that along with the usability engineering data for the reference product already on the market elsewhere.
Clients often seek clarity on whether they need to perform validation studies with Chinese participants and if representation from multiple markets within China (like tier one, two, and three cities) is required. The finalized NMPA guidance specifies the need for a certain sample size per user group, focusing on segmentation. However, it does not require representation from tier one, two, or three cities. As mentioned before, this differs from the draft version of the NMPA guidance, which suggested broader coverage.
Practical considerations for conducting studies in China
Client Question: Do you have the capability to conduct human factors research in China?
Response: Yes, our team has extensive experience and capability in conducting both formative and summative studies in China. We have established relationships with local partners and have successfully conducted studies for clients from around the globe in China for almost 15 years.
Client Question: What are some examples of recent challenging recruits in China?
Response: Conducting studies in China involves unique recruiting challenges, especially for older individuals, those with rare diseases, and physicians. In China, it is highly suggested to include caregivers in the study, even if they do not significantly support the patient, to make them feel more comfortable. Generally, we don’t recommend interviewing people over 50, with 55 as the maximum age without a caregiver present. Chinese people over 50 often have difficulty expressing themselves or communicating their interests. Those in their 60s or 70s, especially with physical conditions, are usually reluctant to talk to strangers like moderators. Having a caregiver present makes them more comfortable and makes recruiting easier, as many will refuse if asked to participate alone.
Physicians are also difficult to recruit and are generally only available for 1-2 hour studies. Workshops and focus groups are rarely feasible due to their busy schedules.
Future trends and recommendations
Client Question: How are clients adapting to the new regulations in China?
Response: With the finalization of the NMPA guidance, clients are increasingly interested in better understanding the Chinese market. Previously, clients may have focused on exporting devices to China without as much consideration for local nuances. Now, driven by the new regulations, there is a shift towards cultural immersion and a deeper understanding of the local market.
The extent to which a human factors validation study is required for a particular device is only one piece of the puzzle. If the trend in China is to follow a pattern similar to what took place in the US, the guidance for conducting a human factors validation study will drive more comprehensive human factors engineering efforts to better understand users and use environments so those insights can be incorporated earlier in the development process.
Conclusion
Navigating the regulatory landscape for medical device research in China involves understanding the specific guidelines and adapting to local challenges. The new NMPA guidance does bring China into closer alignment with the US and EU with respect to the application of human factors engineering, and as in both other regions, there are practical considerations to keep in mind. By leveraging local expertise and focusing on cultural immersion, companies can successfully conduct human factors research in China and ensure their devices meet the necessary safety and effectiveness standards.