July 22, 2026 | Mark Paradies

Change Analysis

Change Analysis

Information Collection Technique

I’ve heard of Change Analysis referred to as a root cause analysis technique. In reality, Change Analysis is a technique used to collect information that can then be analysed to find root causes. In the TapRooT® 7-Step Major Investigation Process (shown below), Change Analysis is one of the techniques used to determine what happened (step 2).

7 step process

In the Equifactor® Equipment Troubleshooting & TapRooT® Root Cause Analysis Course, we also teach Change Analysis as one of the techniques to use when troubleshooting equipment failures.

Simple Change Analysis Example

Probably the simplest example of using Change Analysis is to ask “What Changed?” when you have a problem in a normally trouble-free process or piece of equipment.

Book 4: Major Investigations

The Change Analysis process is described in detail in Book 4 – Using TapRooT® Root Cause Analysis for Major Investigations, Appendix G, by Mark Paradies & Linda Unger, copyright © 2016. The figures below are used here by permission. For this complete example, see pages 246-247 in Book 4.

In the book, there is an example of an old Ford van that wouldn’t idle afetr the truck was started after a tune-up was performed. The following Change Analysis Matrix was developed to investigate what might have changed that could have caused the van to die after it started…

After troubleshooting, the matrix was completed, and it included the following information…

The Change Analysis indicated that the carburetor needed to be disassembled to check whether the idle jet had been clogged. When it was disassembled, a small chunk of robber was found to be blocking the idle jet. When the rubber was removed and the carburetor was rebuilt, the truck started and idled as designed.

Often, Simple is Enough

Sometimes just asking, “What Changed?” is enough to discover valuable information to add to your SnapCharT® Diagram and discover impotant Causal Factors. In more complex examples, you may need an expert in the process or equipment to develop a detailed matrix of the factors that influence performance and what could have changed for each factor.

Learn More About Change Analysis

As previously mentioned, we teach Change Analysis in the 5-Day TapRooT® Advanced Root Cause Analysis Team Leader Chourse and in the Equifactor® Equipment Troubleshooting and TapRooT® Root Cause Analysis Course. See the dates and locations for upcoming public courses by CLICKING HERE.

To schedule a course at your site, contact one of our Implementation Advisors by CLICKING HERE or calling 865-539-2139.

implementation advisors - sales staff

Categories
Interviewing & Evidence Collection, Investigations, Root Cause Analysis, Root Cause Analysis Tips
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