Track 1 Session 6
10:30 to 11:30 a.m. Thursday March 27, 2008

Reliability Predictions for Complex Medical Devices: Field Return and Warranty Forecasts

This presentation will describe the Trixell experience with field returns and warranty cost forecasts. For fielded products, a Weibull analysis approach, based on Maximum Likelihood Estimation, is widely used to build reliability roadmaps. Life data analysis on repairable systems is performed on data from a well-filled after-sale-service database (FRACAS Failure Reporting, Analysis and Corrective Action System). Studies per failure mode allow us to estimate global failure probability during the warranty period. In product life cycle management, the impact on product reliability of major future modifications can also be evaluated by combining Weibull results and discussions with designers. Afterwards, a global Weibull model is deduced for each delivery period and, using the complete field installed base, warranty forecasts are predicted. This presentation will discuss the process and tools used to calculate these estimations, as well as lessons learned.