Using Quality Improvement Tools

WHY-WHY Diagrams

What: A tree diagram that illustrates a chain of symptoms leading to the true cause of a problem by asking "why" each preceding symptom occurred. Sometimes called the 5-why technique, asking "why" five times allows problem solvers to strip way symptoms to get to the true cause of a problem1. There may be  single identifiable cause, several independent causes, or several interrelated ones.

Why: It allow you to isolate potential causes of a problem so you can move on to organizing and measuring data associated with the process.

When: It serves the same purpose as a cause-and-effect diagram but is a simpler tool and can be used in less formal settings and/or situations that primarily involve human factors or interactions or small-scale problem solving.

How:

  1. The WHY-WHY diagram flows from left to right, starting with the statement of the problem to be resolved.
  2. The group then asks why the problem might exist, and responses are  written in a clear statement to the right
  3. Ensure statements are fact- or data-based, and not opinion

Here's a guide and template courtesy of our friends up north, Health Quality Ontario.