Design Controls: Design Review

This is the fourth in a series of articles focused on the design controls process from a standpoint of business acumen as well as meeting customer requirements in the orthopaedic medical device marketplace. Because the design process is controlled and driven by a cross-functional group of individuals, the review of data and the progress of the design project is instrumental in organizing and orchestrating the opening and closing of the various stage gates throughout the evolution of the new product and supporting systems.

What are the basic requirements for and the purpose of design reviews?

Design reviews are formal and intended to provide a systematic assessment of design results, including the device design and the associated designs for production and support processes. This feedback to designers and manufacturing personnel on existing or emerging problems will eventually confirm whether that the project is ready to move on to the next stage of development or not. Because of the formality associated with true design reviews, the following requirements are noteworthy:

  • 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 procedures shall ensure that participants at each design review include representatives of all functions concerned with the design stage being reviewed plus an individual who does not have direct responsibility for the design stage being reviewed, as well as any specialists needed.
  • The individual(s) performing the review shall be documented in the design history file.

Design reviews may have both an internal and external focus. The internal focus centers upon design feasibility and produceability with respect to manufacturing and support capabilities. The external focus is on the user requirements; that is, the device design is viewed from the perspective of the user needs and intended use. Absorbing user needs into the design process with the initial goal of identifying design inputs and (then outputs) can be accomplished at an early externally-focused design review, i.e. taking sometimes subjective user requirements and morphing them into measureable design inputs. This approval of these requirements (inputs) is best organized and presented at design review meetings.

During the initial design stages, issues related to design input requirements will claim the majority of the agenda items. Next, the main function of the reviews may be to evaluate or confirm the choice of solutions being offered by the design team. Following that, issues such as the choice of materials and the methods of manufacture become more important. During the final stages of fulfilling the design plan, issues related to the verification, validation and the transfer of the design into manufacturing will be addressed. These reviewed phase gates can be then approached in a logical progression of content, authority and release actions.

Design assessment activities during the life-cycle of new product development commonly meet the definition of formal design reviews, in that they are intended to be comprehensive, definitive and multidisciplinary in their scope. For example, each design document that constitutes the formal output, or deliverable, of a design task is normally subject to evaluation activities, sometimes referred to as technical reviews. These activities, while they may be called reviews, are often considered to be just verification activities with a purpose to confirm that design output meets design input. Verification activities affect and add to the design output, and are themselves subject to subsequent design review. Companies may conduct routine or ad hoc meetings to discuss an issue, coordinate activities or assess development progress. Decisions from such meetings may not require formal documentation; however, if a significant issue is resolved, this should be documented using design reviews as a vehicle for compliance.

Control of the design review process is achieved by developing and implementing a formal design review process consistent with quality system requirements.

There is a requirement to proceduralize the design review process. What should I include in this procedure?

The manufacturer should have documented formal design review procedures addressing the following:

  • Evaluation of the design (including identification of concerns, i.e., issues and potential problems with the design)
  • Resolution of concerns
  • Implementation of corrective actions

Due to the far-reaching ramifications of these design reviews, this procedure should include strategic and tactical linkages with the quality management system, as well as post-production implications having to do with redesign arising from adverse events and functionality issues, systemic process issues with causation imbedded in input requirements being inadequately met, validation results that do not address intended use and poorly conceived and documented transfer (to manufacturing).

To meet the design review comprehensive requirement, proceduralized assessments should include a formal review of the main device and subsystems, including accessories, components, software, labeling and packaging; production and resource needs; and installation and service, if needed. The scope includes performance, physical safety, compatibility with other devices, overall device system requirements, human factors and environmental compatibility. I find that this type of detail can be expressed in a work instruction-level document that goes into the details of expected outputs related to quality systems and input requirements.

This design review procedure should at least include linkages to:

  • responsibility and authority for delineating decision-making based upon the ability and foreseeable outcome
  • controlling documentation and proper recordkeeping
  • design planning to assure that logistical and philosophical requirements are carried out at strategic times and that verification activities are always part of the scheme
  • competency of reviewers in terms of education, background and experience
  • manufacturing controls and those players involved with designing aligned processes for producing this medical device
  • risk management practices to assure that quantitative consequences are studied and mitigated
  • follow-up based upon cause and effect
  • transfer of the design history file contents to the device master record, i.e. the outputs of design
  • explain the design implementation that is focused on finding problems, not resolving them.
  • show how corrective and preventive actions are trended and facilitated along this (reviewed) critical path
  • show how service and repair is assimilated into the plan and developed along with process / product risks and after sale scenarios.

How many reviews should be conducted during this process of product and process development?

However many design reviews your teams may have during this process depends a lot upon the complexity of the device and the range of intended uses that are identified. Each of these criteria is directly proportional to the variableness of the end product and supporting processes. As the design project proceeds toward closure the cost of correcting design errors increases exponentially, because the flexibility to implement optimal solutions decreases as more variables are “set in stone” as design outputs. Thus, formal design reviews should be planned to detect problems early. Typically, formal reviews are conducted at the end of each phase and at important milestones in the design process. It is advantageous in almost every instance to conduct a formal review of the design input requirements early in the development process. As I said previously, the number of reviews (as planned) depends upon the complexity of the device. Here are some simple rules of thumb:

  • For a simple design or a minor upgrade to an existing product, it might be appropriate to conduct a review at the beginning and then at the conclusion of the design process. Conducting formal design reviews at the end of the design process usually means that engineering essentially completes the design, tests an engineering prototype and conducts a formal design review prior to turning the design over to manufacturing. The initial design review launches the design plan into motion to accomplish these simple tasks.
  • For a product involving multiple subsystems, an early design task is allocation of design input requirements among the various subsystems. Reviews will be necessary with greater frequency, with more player cross-functionality.
  • For complex systems, additional reviews are often built into the development plan. In such cases, an additional review will be needed after the design has been validated using production devices.

The manufacturer must establish a reasonable rationale for the number and type of reviews based on sound judgment, risks involved and the complexity and variableness of the product and ancillary process steps.

Who should I invite to design review meetings? Should I form a core team of reviewers?

In determining who should participate in a formal design review, planners should consider the qualifications of reviewers, the types of expertise required to make an adequate assessment and the independence of the reviewers. Formal design reviews should be conducted by persons having technical competence and experience at least comparable to the developers. For a small manufacturer, this may require that an outside consultant be retained to participate in the evaluation of the design.

There is a requirement in 21 CFR, Part 820.30 that indicates that an independent person attend all formal reviews to make an independent assessment and submit observations and recommendations to the reviewers. Within the context of formal design reviews, the practical solution is simply to ensure a fresh perspective, based on the principle that those who are too close to the design may overlook design errors.

Thus, reviewers will often be from the same organization as the developers, but should not have been significantly involved in the activities under review. A manufacturer will often employ one or more specialists to conduct certain types of specialized assessments which are beyond the capabilities of the designers. Such specialists may be assigned to participate in the formal design review. Manufacturers should carefully consider which interests should be represented at formal design reviews. Subtle distinctions in reviewer perspective may have a dramatic impact on overarching outcome and affect the critical path of assuring that intended use is addressed robustly.

I have read about so many approaches to conducting design reviews. What is best for my company?

Persons who are making presentations should prepare and distribute information to help clarify review issues and help advance the review. However, the intent of the quality system is not that presentations be so formal and elaborate that designers are spending excessive time on presentations rather than on designing a safe and effective device.

There are many approaches to conducting design review meetings. In simple cases, the technical assessor and reviewer may be the same person, often a project manager or engineering supervisor, and the review meeting is a simple affair in the manager's office. For more elaborate reviews, detailed written procedures are desirable to ensure that all pertinent topics are discussed, conclusions accurately recorded and action items documented and tracked.

Like all well-thought-out meetings, design reviews should be planned, documented with an agenda and formal minutes/deliverables, include a sign-in sheet for attendees (with a space for the independent reviewer or expert, ad hoc invitee) and follow-up from previous sessions. A facilitator should lead the review and moderate proceedings, keeping them on schedule and on topic.

Design review meetings can become adversarial affairs. The reputation of the designers tends to be linked to the number of discrepancies found, causing designers to become defensive, while the reviewers score points by finding weaknesses in the design. The resulting contest can be counterproductive. An added complication is the presence of invited guests, often clinicians, who are expected to provide the user perspective. These reviewers are often very reluctant to ask probing questions, especially if they sense that they may become involved in a conflict wherein all the rules and relationships are not evident.

These activities can be avoided by having a clearly stated procedure that establishes the goals and ground rules for conducting the formal design review. Participants should be encouraged to ask questions, avoid making assumptions, and should think critically. The focus must remain on the design, not the participants. To reiterate, the focus lies upon the design and not the political implications caused by “turf-battles,” failures attributed to the incompetency of engineers, regulatory people, manufacturing engineers, etc., missed dates because of the lack of organizational skills and demands, rushed decisions because of marketing/sales pressures, etc.

Not all formal design reviews involve meetings. For extremely simple designs or design changes, it may be appropriate to specify a procedure in which review materials are distributed or circulated among the reviewers for independent assessment and approval. However, such a procedure negates the benefits of synergy and teamwork, and should be considered only in cases where the design issues are limited in scope and well defined. I have yet to see this work on an ongoing basis. A hybrid is preferable. Having these independent assessments can be beneficial some of the time, but not all of the time.

There is wide variation in the way companies implement decision-making processes. The reviewers are given the authority to make decisions and commit resources to resolve problems. The approach used should be documented to show that reviews can often leave unresolved issues. Review procedures should include a process for resolving differences, and should provide reviewers with enough leverage to make accurate decisions while protecting the integrity of the process. If the solution is not readily evident, the reviewers may specify the appropriate corrective action which necessitates investigation and verification of effectiveness.

What affect does design review have on design verification and validation activities, if any?

In practice, design review, verification and validation will invariably overlap one another, and the relationship among them may become confusing to the reviewers. The general rule for this sequence of events is: verification, review, validation, review.

Verification activities are almost always completed prior to the design review. These verification results are then submitted to the reviewers along with the other design output to be reviewed.

Some verification activities may be treated as components of the design review, particularly if the verification activity is complex and requires multidisciplinary review.

Design validation typically involves a variety of activities, including a determination that the appropriate verifications and reviews have been completed. Thus, at the conclusion of the validation effort, a review is usually warranted to assure that the validation is complete/adequate. Another general rule is that successful verification can lead to validation when the reviewers draw consensus from results, investigations and successful mitigation of issues.

Lastly, what is the function of the design history file in relationship to design reviews?

The design review meeting results are made a part of the device design history file. The results should include minutes and notes, or annotated draft drawings and annotated draft procedures that played a significant role during the design review. Such documents help show that plans were followed, verification/validation was reviewed and, to some extent, how the design evolved.

I have been part of some design reviews that use a form to capture some of this information for minutes such the device, date, moderator, attendees, major phase, problems, assignments, etc. The device design review minutes are a key and required part of the design history file. The minutes are similar to a journal in many ways. Keeping a comprehensive “journal” will greatly assist investigations done post-commercialization and will be helpful in case of adverse events defense. I am big proponent of keeping copious notes and being able to show the history of the device as it is developed. When the design effort is completed and the initial production of devices is transferred to production and produced per the device master record, you will be able to go back to the design reviews (now located in the design history file) and comprehend where these devices “came from.” History is so important from a standpoint of stages and goals met, facilitation of authority for decisions established, mitigation of problems are documented completely, that the outputs of design meet the inputs related to user needs and intended use and that, above all, your team has developed a safe and functionally effective medical device for human use.

John Gagliardi has had success over the past 40 years in the Medical Device and Pharmaceutical industries because of his practical approach to process-orientation and business. He has been actively involved in research and development, quality assurance, training, operations, process architecture, FDA inspections and regulatory affairs. John specializes in building systems in a compliant and business-ready manner. Email John at   This email address is being protected from spambots. You need JavaScript enabled to view it.  .

MidWest Process Innovation, LLC
7736 Woodside Court
Maineville, OH 45039
513-573-0085 (phone)

Looking Back at Design Controls: A Six-part Series

Part I: A Business-Critical Tool. (BONEZONE Fall 2009) A systematic and organized approach is the goal in taking product-feasible ideas and bringing a finished device to market. The synergistic and harmonized relationship of all “players” involved is the key to commercializing devices, and meeting customer needs and regulatory requirements.

Part II: The Requirement for Planning. (BONEZONE Winter 2009) Having a written plan is not only a regulatory requirement, but also the “point of order” that is necessary to stay on course and control the destiny of an idea.

Part III: Inputs and Outputs in Synergy. (BONEZONE Spring 2010) Development of a solid foundation of requirements is the single most important design control activity.

Part IV: Design Review. (Current issue) Design reviews may have an internal and external focus. The internal centers on design feasibility and produceability with respect to manufacturing and support capabilities. The external centers upon user requirements.

Coming Next:

Part V: Design Verification and Validation. (BONEZONE Fall 2010) Design verification is almost always done vs. specifications. Therefore, to control the specifications and increase the probablility of achieving desired safety and performance characteristics, device, software, labeling, packaging and any other specifications should be complete and thoroughly reviewed before development continues.

Part VI: The Wrap-up - Transfer, Changes, the History File. (Coming in BONEZONE Winter 2010)