ABSTRACT

Risk management and its elements of risk analysis, hazard analysis, risk evaluation, and risk control have been used as an engineering tool for many years in industries such as nuclear power, weapons systems, and transportation to identify risks and to control system modes of failure. Recently the health care industry has seen increased attention to risk-management tools since they have the potential to improve patient safety These tools and related meth­ ods have been applied to understanding “use errors” made with medical devices. Use errors are defined as predictable patterns of human errors that can be attributable to inadequate or improper design. Use errors can be predicted through analytical task walk­ through techniques and via empirically based usabil­ ity testing. This chapter explains and discusses the special methodology of use error focused risk analy­ sis and some of its history. Case studies are pre­ sented that illustrate the methods of use error risk analysis such as fault tree analysis (FTA) and failure mode effects analysis (FMEA) and some pitfalls to be avoided. The case studies include the Therac-25® computer-controlled radiation therapy

system and an automatic external defibrillator (AED).