Author: Suzanne Broussard

Performing a methodologically sound literature review in the early stages of product development, as well as in the later stages, can help reduce most of the inadequacies highlighted by the European Commission in section A6 of MEDDEV 2.7/1 revision 4.  Section A6 provides examples of studies that lack scientific validity for the demonstration of adequate clinical performance and/or safety.

Here are the seven areas highlighted in section A6 of MEDDEV 2.7/1 revision 4 that manufacturers tend to have the most problems in proving scientific validity:

1. Lack of information on elementary aspects: This includes missing elementary requirements of the clinical evaluation such as methods, results of clinical studies, observed undesirable side effects, and details on the intend-to-treat population.
2. Numbers too small for statistical significance: This may include publications and reports with “inconclusive preliminary data, inconclusive data from feasibility studies, anecdotal experience, hypothesis papers and unsubscribed opinions.”
3. Improper statistical methods: The examples given are centered around 3 scenarios. 1) No corrections applied to multiple comparisons. 2) Calculations and test were used that are based on a certain type of distribution data while the distribution is not tested, not plausible, or data were not transformed.
4. Lack of adequate controls: It is possible to cause bias or confounding in single arm-studies and in other studies that do not include appropriate controls in the following situations: results based on subjective endpoint assessments, endpoints subject to natural fluctuations, studies with subjects that are likely to take effective co-interventions, other influencing factors, or when publications indicate there may be variables and ill controlled factors.
5. Improper collection of mortality and serious adverse events data: In situations where mortality studies and other studies that may result in serious outcomes, there must be procedures in place to “investigate serious patient outcomes, numbers of subjects lost to follow-up, reasons why subjects leave the study, and the results of sensitivity analysis should be fully disclosed in reports and publications.”
6. Misinterpretation by the authors: Conclusions must be in line with the results section.
7. Illegal activities: All clinical investigations must be in compliance with local regulations, as well as designed, conducted, and reported in accordance with EN ISO 14155 or a comparable standard, and the Declaration of Helsinki.

In a recent post, we talked about one of the most challenging areas of the CER: Defining Measurable Safety and Performance Endpoints

The first deficiency listed, “lack of information on elementary aspects,” can obviously be improved using a robust systematic literature review. Defining the evaluation criteria is the first step in performing a methodologically sound systematic literature review, and these sections would then fall into place. For example, one criterion would define the clinical study methods, while other criteria might include clearly defining results to be included, undesirable side effects, and the intended-to-treat population. A scientifically sound approach and well-organized data management plan can bring all the clinical data together and allow for a thorough understanding of where the device is in the process of obtaining an CE marking.

Less obvious is how a methodologically sound systematic literature review can help with some of the other CER deficiencies. Let’s look at the three points in a devices lifecycle in which clinical evaluation is undertaken: development of the medical device (section 6.2.1), initial CE-marking (section 6.2.2), and updating the clinical evaluation (section 6.2.3).

The systematic literature review can be an effective tool early in the development of the medical device for gap analysis and determining State-of-the-Art. Once all the clinical evidence is gathered it is much easier to see if the publications and report documents have conclusive preliminary data or if further clinical data is required before moving forward with CER submissions. And, closely evaluating the complied data makes it easier for manufacturers to note statistical methods in the supporting data, and the potential of bias.

Of course, not all inadequacies can be addressed with a systematic literature review, such as improper collection of mortality and serious events data that rely on a different process for review. It is always important to collaborate with your organization’s regulatory authorities or a regulatory specialist to make sure you are complying in these areas.

Following leading practices and presenting clinical data in a straight-forward manner helps manufacturers be in good position to help regulatory agencies not to have to say No to your CER submission. Lack of organization and transparency can create a cycle of generating responses to regulatory agencies and delays getting devices to market.

Systematic literature reviews can help you find gaps in information that may be needed for inclusion in the CER, as well as putting your best foot forward by strongly providing sufficient clinical evidence for the evaluation of safety and performance of the device. Regulatory agencies expect this level of compliance. We can help you meet the challenge. We are experts in this area. Check out our recent webinars to better understand the process.

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At Criterion Edge, we are experts at generating methodologically sound systematic literature reviews and state-of-the-art reports to ensure your CER is ready for review by notified bodies. And, we can help ensure the scientific validity is adequate and document the methods we use for data collection. Talk to us about running a systematic literature review for you.