DESIGN VERIFICATION IN THE MEDICAL DEVICE INDUSTRY
Author: Ward, James R
Supervisor: Clarkson, P. John
Institution: Cambridge University Department of Engineering
Mark Twain, 19th Century American humorist, once said, “All you need in this life is ignorance and confidence, and then success is sure.” Whilst blind optimism may sometimes be advantageous in life in general, anyone who followed such a philosophy when designing medical devices would risk any number of potentially catastrophic problems in such a regulated and safety-critical industry. Indeed, poor device design almost certainly causes many serious injuries – and even deaths – each year in the UK [Ward and Clarkson, 2001]. In medical device design, ignorance is unethical and confidence is insufficient – objective proof that requirements have been met must be provided through verification. Yet, how should such proof be collected: What method should be used? How thorough should the process be? When in the design process should this occur? Whilst much guidance exists on how to design, there is a dearth of generic guidance on how to verify. Generally, such guidance simply says: “Do verification”. In response, research was undertaken to investigate the verification process. Through a literature review, case studies, interviews and a questionnaire, an understanding of the ‘mechanics’ of the verification process was developed, including how the above questions might be answered and what factors might influence the decisions. Further work investigated current verification practice in a number of medical device design companies and found various problems related to verification, and that further guidance was indeed required, particularly by those who design innovative and complex devices. A workbook was developed for providing assistance on a “good practice” approach to verification, and was evaluated by experienced professionals who were involved in the design of medical devices, including designers, managers and regulatory personnel. Following much positive feedback, a finished version of this workbook is now being published for use in the medical device design community.