Medical Devices

medical-device-analyticsResearch and Development. Design controls. Process validation. Manufacturing. Medical device manufacturers have the need for the proper application of statistics throughout the product lifecycle.

In fact, 21 CFR 820.250 (a) states, “Where appropriate, each manufacturer shall establish and maintain procedures for identifying valid statistical techniques required for establishing, controlling, and verifying the acceptability of process capability and product characteristics.”


Design Controls: The application of statistical methods is prevalent across all phases of design controls. Design outputs requires the need for setting specifications. Design verification requires the application of risk management tools, biocompatibility, and equivalence testing for design comparisons. Design validation requires the application of risk management tools, design of experiments (DOE), statistical process control (SPC), and process capability. The application of DOE is required in both design transfer and design changes.
Reliability: A reliable design of medical devices ensure they will last a minimum life. Statistical methods quantify the failure distributions, probability of survival, impact of external factors, and the expected degradation.

Process Validation: According to 21 CFR Part 820, medical device manufacturers are required to validate as well as monitor and control parameters for their processes. The guideline on Quality Management Systems does not specify how this is accomplished; only that “a process is established that can consistently conform to requirements” and “studies are conducted demonstrating” this. Thorough process development, optimization, and control using appropriate statistical methods and tools are recommended for demonstrating your process is both stable and capable. The efficient and effective application of recommended statistical methods and tools are essential throughout Installation Qualification (IQ), Operational Qualification (OQ), and Performance Qualification (PQ).

Process Control and Capability: Design of SPC programs and implementation of advanced monitoring and assessment analytics such as real time multivariate SPC are essential to medical device manufacturers, from process validation through product discontinuation (in manufacturing).

Acceptance Sampling: 21 CFR directs medical device manufactures to establish, maintain, and document acceptance procedures for: receiving acceptance activities, in-process acceptance activities, and final acceptance activities. Each of these are direct applications of acceptance sampling.

Text Mining/Analytics: The majority of stored data in medical device manufacturing is not numerical; it is in the form of unstructured text in reports and documents. The use of text mining/analytics is emerging for analyzing product complaints, non-conformances, recall information, and inspection observations.

Specifications/Acceptance Criteria: Scientifically sound application of statistical analysis is essential for developing acceptance criteria for both measurement systems and process validation. In addition, 21 CFR requires valid statistical techniques to be used to ensure process capability (which relies on setting meaningful specifications).

Measurement Systems Analysis (MSA): Process validation, manufacturing, and quality rely on having accurate and precise measurement systems. Thorough use of statistical methods and sound experimental design is essential to support the development and validation of acceptable accurate, precise (gauge R&Rs), and stable measurement systems.