PS 102 Lesson 1: The Swiss Cheese Model
The adverse events that we hear about are the tragic ones, where a patient has been harmed, or worse, killed. Serious harm, such as removing the wrong leg or sending a newborn home with the wrong parents, grab sensational headlines.

How do such events occur, even when there are systems in place to prevent them? And do all such events involve human error? In this lesson, we’ll take a look at the relationship between error and harm.
Estimated Time of Completion: 20 minutes
Learning Objectives
After completing this lesson, you will be able to:
1. Summarize the relationship between error and harm.
2. Describe the Swiss cheese model of accident causation.
3. Define latent error and its role in causing harm.
Contributors
Author(s):
Fran Griffin, RRT, MPA, Consultant, Fran Griffin & Associates LLC View Profile
Editor(s):
Laura Fink, Senior Managing Editor, Institute for Healthcare Improvement View Profile
Stephanie Garry Garfunkel, MA, Managing Editor, Institute for Healthcare Improvement View Profile
Kathleen Vega, BA, Freelance Writer, Kathleen B. Vega, Inc View Profile
Reviewer(s):
Lucian Leape, MD, Adjunct Professor of Health Policy, Harvard School of Public Health View Profile
Requirements
You must be a registered IHI.org user to take this lesson.
You must achieve a minimum score of 75% to successfully complete this lesson.