Track 2 Session 9

2:20 to 3:20 p.m. Wednesday, June 16, 2010

A Case Study of Medical Device Risk Assessment Using Exponentially Distributed Failure Data

ISO 14971 defines risk as the probability of occurrence of harm and the severity of that harm. This presentation is a case study that demonstrates the application of risk assessment to a rare occurrence of Automated External Defibrillator (AED) failures due to a stackup of tolerances in the device and an unusual user stimulus. An analysis of the AED internal device history log from recalled devices showed the device failures followed the exponential distribution. Analyzing both the use profile of the AEDs and the estimated failure rate provided an estimate of the probability of occurrence during a critical life-saving situation. This probability estimate was then applied to the population at large to estimate the risk of potential harm to the user population.

Key Words: Risk Analysis, Medical Device, Exponential Distribution, Probability

Greg Lancaster

Philips Healthcare

Seattle, Washington