12 April, 2016 Matthew M. Lowe, Executive Vice President, MasterControl
Design engineers must ensure
that all necessary documentation
pertaining to design control is in place.
Design control issues represent a key challenge for many medical device firms. This is the reason why in 1996, the U.S. Food and Drug Administration (FDA) added design control principles to 21 CFR Part 820 and required rigorous documentation to demonstrate design control.
The revision required manufacturers of some Class I and all Class II and Class III devices to follow the conditions and parameters provided under Subpart C, Section 30 of 21 CFR Part 820, also known as the Quality System Regulation (1). The mandate added a whole new level of complexity to the already rigorous and challenging device development process. In addition to designing and testing devices, development engineers must also ensure that all necessary documentation pertaining to design control is in place. This amounts to hundreds if not thousands of documents for every single product launch.
Under 21 CFR Part 820.30, there are nine elements of design control, each one requiring strict documentation. Let’s take a look at these elements and what the documentation burden of each means (2).
Design and Development Planning or DDP: “Each manufacturer shall establish and maintain plans that describe or reference the design and development activities and define responsibility for implementation…The plans shall be reviewed, updated, and approved as design and development evolves.”
Tip #1: This requirement indicates that design control is intended to be a prospective activity in the development process. You must incorporate a planning period into your development process upfront to ensure timely product launch and minimize your risk of product failure. A key part of DDP is assignment of tasks to responsible parties. Make sure your DDP process allows timely communication among those parties.
Design Input: “Each manufacturer shall establish and maintain procedures to ensure that the design requirements relating to a device are appropriate and address the intended use of the device...The design input requirements shall be documented and shall be reviewed and approved by a designated individual.”
Tip #2: Many manufacturers mistakenly assume that user requirements gathered by their marketing teams are sufficient as design input requirements. It is a good starting point for developing design input, but it’s not enough because most of the time, that information is qualitative, and therefore, insufficient.
You need quantitative design input that can be easily measured. Good sources of design input include prior generation customer complaints, medical device reporting (MDR), corrective action and preventive action (CAPA), sales feedback, marketing surveys, user conferences, and competitor products.
Design Output: “Each manufacturer shall establish and maintain procedures for defining and documenting design output in terms that allow an adequate evaluation of conformance to design input requirements…Design output shall be documented, reviewed, and approved before release….”
Tip #3: The design output refers to the completed device at the end of the development cycle, but it’s not limited to the finished device. Your design output should include all documentation during the development process verifying that the design input requirements were met—plus any item that serves as a basis for the finished device specifications.
Design Review: “Each manufacturer shall establish and maintain procedures to ensure that formal documented reviews of the design results are planned and conducted at appropriate stages of the device's design development…The results of a design review…shall be documented in the design history file (the DHF).”
Tip #4: Design reviews, which are crucial to the efficacy of the design control, should be planned for upfront in the DDP because changes late in the design cycle are more costly than those made early on. You can avoid expensive non-optimal redesigns close to the launch date by conducting design reviews—and identifying changes—sooner than later.
Design Verification: “Each manufacturer shall establish and maintain procedures for
verifying the device design…The results of the design verification, including identification of the design, method(s), the date, and the individual(s) performing the verification, shall be documented in the DHF.”
Tip #5: Compare your design output with your design input to determine if design requirements were met. There are many forms of design verification. Risk analysis is part of design verification and will commonly take the form of Failure Modes and Effects Analysis (Design FMEA). The ultimate goal of this step is to verify that the design output meets the engineering specifications that were derived from the user needs.
Design Validation: “Each manufacturer shall establish and maintain procedures for validating the device design…The results of the design validation, including identification of the design, method(s), the date, and the individual(s) performing the validation, shall be documented in the DHF.”
Tip #6: Take note that design verification precedesdesign validation and is not a substitute for the latter. QSR requires validation testing to be conducted on actual production units or their equivalents. When using equivalents, you must provide documentation that clearly demonstrates the equality. Don’t manufacture test units under special conditions that don’t mimic actual production. This step is intended to validate that the engineering specifications were translated properly from the user needs and thus the design output does indeed meet the user need defined in the design-input phase.
Design Transfer: “Each manufacturer shall establish and maintain procedures to ensure that the device design is correctly translated into production specifications.”
Tip #7: At minimum, the design transfer process must assess the completeness and correctness of the production specifications. Furthermore, the specifications must be reviewed and approved and placed under the formal change control process. Most of all, you must make sure that the product is manufactured only to the latest approved revision of the device master record.
Design Changes: “Each manufacturer shall establish and maintain procedures for the identification, documentation, validation or where appropriate verification, review, and approval of design changes before their implementation.”
Tip #8: After you have finalized and approved the design input requirements, any changes are subject to formal change control process. Once you have verified and validated the design output specifications, any changes will also require change control. This entails documentation and evaluation of every design change, although it doesn’t mean every single change requires the same level of scrutiny.
Design History File: “Each manufacturer shall establish and maintain a DHF for each type of device. The DHF shall contain or reference the records necessary to demonstrate that the design was developed in accordance with the approved design plan and the requirements of this part.”
Tip #9: The DHF is intended to serve as the repository of documentation generated by the design control process, with each of the elements discussed above contributing documents to the DHF. Make sure you assemble your DHF properly because it will be referenced throughout the life of the product. The DHF is crucial when a question arises about the design’s integrity long after a product has been launched. A manufacturer could pay a high price for an inadequate DHF if such a question leads to a recall of several years’ worth of product.
Leverage 9 Elements
Design control is meant to help you develop and manufacture safe and effective products that readily comply with regulations. If you leverage the nine elements discussed above, they will help you focus on building your core competency, instead of just fulfilling regulatory requirements.
Matthew M. Lowe is a mechanical engineer with over a dozen years of medical device experience in product development, product management, and regulatory compliance. Prior to joining MasterControl in 2006, he worked in product development and product management at Ortho Development Corp. and Bard Access Systems. He has successfully launched more than a dozen medical devices and has four patents issued. His regulatory compliance experience includes writing a 510(k) that was cleared by the FDA and managing a multisite, multiyear post-market clinical study for orthopedic devices.
(2) These elements are defined in 21 CFR 820. 30 (a) through (j). From FDA website,