Swiss Cheese Model
Originally developed by James Reason to explain how system failures occur, the swiss cheese model is widely used to explain errors in health care. In this model each slice of cheese represents a barrier or safety check designed to prevent an error. While no barrier is foolproof it is thought that it is a rare event for all the barriers to fail or all the holes to line up and the error to reach the patient. Thus named the swiss cheese effect where all the holes in the swiss cheese line up.
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