Although Regulation (EU) 2017/745 on medical devices (MDR) does not explicitly mention surveys, they are recognized in applicable standards and guidelines as valid methodologies for data collection, particularly within Post-Market Clinical Follow-up (PMCF) activities.
The use of surveys is especially beneficial when a moderate level of clinical evidence is required or when data needs to be collected in a structured manner, avoiding more costly and complex methods. Surveys can be used to monitor data over time—by administering the same questions to different respondent groups—or to explore preliminary clinical hypotheses before proceeding with more advanced studies.
Compared to traditional clinical investigations, surveys allow manufacturers to reach a large number of users, enabling the collection of substantial data in real-world settings. This approach supports the generation of more representative insights into the use of a medical device in everyday practice. However, in cases of limited distribution, the data collected may be insufficient or not representative of the entire population, compromising the generalizability of the results.
Survey level 8 vs survey level 4
As outlined in Appendix III of MDCG 2020-6, surveys can be divided into two main categories:
- Level 8 Surveys (general PMCF survey)
Level 8 surveys are designed to gather general feedback from users or patients based on their past experience. These are retrospective, collecting information on device usage over a previous period. Each participant completes the survey only once, providing an overall assessment of the device’s usability, functionality, and perceived effectiveness over time.
Level 8 surveys are particularly suitable for low-risk devices or those intended for short-term use, where continuous clinical monitoring is not required. They are also commonly used for widely adopted devices whose side effects or usability issues are already well known and do not necessitate in-depth clinical investigation.
Although relatively easy to administer and less expensive than other methods, the quality of data collected tends to be lower, making these surveys more appropriate for exploratory purposes or as a complement to other sources of evidence. - Level 4 Surveys (high-quality PMCF survey)
Level 4 surveys are used to collect more robust and detailed evidence, essential for high-risk devices, newly marketed products, or those intended for long-term use. Unlike Level 8 surveys, these collect specific information related to individual patients, based on carefully monitored clinical data to ensure the relevance and reliability of the findings.
These surveys may be retrospective or prospective, and participants can be involved in multiple data collection phases, providing updates on treatment progress or device usage. The questions are designed to gather data related to clear and measurable parameters. The sample size must be sufficiently large to ensure statistical reliability of the results.
The choice of survey type depends on the required level of evidence, which is determined by the device’s risk profile, time on the market, and availability of existing data. For low-risk, well-established devices, extensive clinical monitoring is generally unnecessary, making Level 8 surveys appropriate. Conversely, for high-risk or newly introduced devices, it is essential to collect more specific data through Level 4 surveys to ensure accurate assessment of safety and performance over time.
Phases of data collection via survey
To ensure the reliability and validity of the data collected, the design and administration of a survey must follow a well-structured process, divided into several key phases:
- Planning
The initial phase involves clearly defining the objectives of the survey, with particular attention to the risks associated with the medical device in question, as well as the availability and quality of existing data. A gap analysis may be useful at this stage to identify missing data that should be addressed through the new collection effort.
For high-quality surveys, it is essential to draft a PMCF Survey Plan, which should detail the key aspects of data collection, including:
- Description of the device (technical features, indications, and usage modalities)
- Objectives of the survey
- Justification of the design
- Definition of endpoints and acceptance criteria
- Inclusion and exclusion criteria
- Data analysis plan (analytical methodologies and statistical tools to be used)
- Data collection methodologies
- Identification of survey sites and respondents
- Procedures for early termination
- Survey Design
The formulation of questions must be clear, neutral, and easily understandable to minimize the risk of biased responses or misinterpretation. The choice of question format (closed, semi-closed, or open) should be carefully considered based on the specific objectives of the research.
Where possible, reference should be made to existing literature to identify validated surveys that can be used in full or adapted, allowing for comparison of results with previous studies and enhancing the validity and comparability of the data collected.
The survey should be structured into thematic sections, including:
- Screening section: to select eligible respondents
- Main section: containing questions related to the patient, the device, procedural aspects, device performance, safety, and other relevant factors
Appropriate statistical tools can be used to verify the internal consistency of the survey, ensuring that questions are interrelated and consistently measure the same variable, thereby increasing the reliability of the data collected.
Additionally, it is advisable to assess the readability and comprehensibility of the survey using readability tools. This process helps ensure that questions are easily interpreted by respondents, reducing the risk of misunderstandings and improving the overall quality of the data collected.
- Methodological validation
Once the PMCF survey has been drafted and approved, the next phase involves preparing it for distribution, typically using dedicated software. This includes configuring questions and response options, setting up skip logic and branching questions, and applying validation rules to ensure data quality.
Subsequent internal testing and validation activities are carried out to identify and resolve any system issues. - Data collection and management
During data collection, it is essential to implement quality control systems to continuously monitor the reliability of the information and ensure the representativeness of the sample.
Effective data management depends on the adoption of appropriate technologies that ensure secure collection, storage, and handling of information, in full compliance with data protection regulations. - Data analysis and interpretation
Once the required sample size is reached, the data analysis and reporting phase begin. The analysis must be thorough and include all collected information, with a particular focus on parameters related to device safety and performance, in relation to the predefined endpoints and acceptance criteria.
Additionally, insights into device usage can provide valuable input for understanding its application in clinical practice and guiding potential design modifications or revisions to the Instructions for Use and risk management files.
A well-designed survey, supported by careful statistical analysis and methodological validation, is a valuable tool for collecting structured clinical data.
Following a clearly defined process—from planning to data collection, management, and analysis—enables the generation of reliable and actionable insights into device usage in clinical practice and helps identify potential areas for improvement.
