Root Cause Analysis Methods

All businesses experience some level of challenge, whether it’s systems or processes not working properly, issues in production, problems with customers, or a myriad of other issues that may arise.

Ignoring problems is unlikely to be beneficial in the long run. What distinguishes effective businesses from others is their ability to problem-solve. When faced with an issue it’s important to rapidly get to the cause, and then put in place a solution that stops it from repeating.

In today’s article, we’ll be looking at root cause analysis and how you can use this method within your business to understand what’s causing issues.. You can then use the results to plan an improvement activity to fix the problem.

What is Root Cause Analysis

Let’s take a brief look at what is Root Cause Analysis:

  • Root cause analysis is a methodology. It’s used to identify causes for business issues like defects or problems within a process or system. 
  • Root Cause Analysis (often referred to as RCA) is an important tool which is typically part of a Quality Management continuous improvement toolset.
  • It can help organizations to address issues at their source rather than simply treating whats visibly apparent (i.e. the symptoms). 
  • Effective businesses utilize RCA as it helps improve processes, enhance product quality, and prevent recurrence of problems, leading to increased efficiency and removing negative impacts on the customer.

Characteristics of Root Cause Analysis

Root Cause Analysis has several key characteristics, these include:

  • RCA follows a structured process to get to the root of the problem.
  • It focuses on prevention – The primary goal is to prevent the recurrence of issues.
  • It’s usually Data-Driven – RCA relies on data collection and analysis to identify the root causes.
  • It’s usually Cross-Functional – It often involves team members from different departments to provide diverse perspectives.
  • It’s iterative – It may require multiple iterations to identify all root causes and might use a hypothesis which can be tested.
  • It utilizes business documentation – Detailed documentation is maintained throughout the process.
  • It’s Action-Oriented: – not only does it require “doing”, it’s often fast-paced, enabling a business to fix, monitor and improve.

What Are the 7 Root Cause Analysis Techniques?

There are several established root cause techniques.  

Some of these suit certain circumstances better than others, but all are fairly lightweight improvement techniques.

They are all fairly easy to learn – don’t require expensive software, and you can swiftly train your team so that they can actively participate.

Here are some of the more widely used techniques:

1. 5 Whys

The 5 Whys technique involves asking “why” repeatedly (typically five times) until the root cause of a problem is identified. This method helps drill down into the details of an issue.

2. Fishbone Diagram (Ishikawa)

Also known as the cause-and-effect diagram, this tool helps visualize the potential causes of a problem by categorizing them into branches. Each branch represents a category of potential causes.

3. Failure Mode and Effects Analysis (FMEA)

FMEA is a proactive method used to identify possible failure modes and how they might impact your system or processes. It can help prioritize the issues based on their severity, occurrence, and detectability.

4. Pareto Analysis

Pareto Analysis which can sometimes be referred to as the 80/20 rule, identifies the most significant causes of a problem by focusing on the causes that contribute to 80% of the issues.

5. Fault Tree Analysis (FTA)

FTA is a top-down approach that uses logic to identify the various paths to failure. It visualizes the pathways that lead to the root cause.

6. Root Cause Mapping

This technique involves creating a visual map of all possible causes of a problem and their interrelationships. It helps in understanding complex systems and identifying root causes.

7. Scatter Diagram

A scatter diagram plots data points to identify correlations between potential causes and the problem. This method is useful when the relationship between variables needs to be understood.

What Are the 5 Steps of Root Cause Analysis?

While each method might go about the process differently, they all have some common process steps- let’s have a look at these:

1. Define the Problem

Clearly articulate the problem, including its symptoms, scope, and impact. Understanding the problem fully is crucial for effective analysis.

2. Collect Data

Gather relevant data related to the problem. This includes data on when the problem occurred, the conditions under which it happened, and any patterns that can be identified.

3. Identify Possible Causes

This is often a team task where the team use techniques such as brainstorming to identify potential causes of the problem.  This can use data or peoples experience.

4. Analyze the Causes

Investigate the potential causes to identify the root cause. 

5. Develop and Implement Solutions

Once the root cause is identified, develop solutions to address it. Implement these solutions and monitor their effectiveness to ensure the problem is resolved.

The 5 Why Method for Root Cause Analysis

Five Why is another common problem-solving tool that is often used to explore the cause-and-effect relationships underlying a particular problem. 

The technique involves asking “why” five times (or as many times as needed) to move past the symptoms of a problem and uncover the root cause.

Let’s have a look at an example:

Frame the Problem: The manufacturing line has stopped.

1 – Why? – Because the conveyor belt stopped moving.

2 – Why? – Because the belt motor has overheated.

3 – Why? – Because the motor’s cooling fan stopped working.

4 – Why? – Because debris got into the fan.

5 – Why? – Because there was no protective cover on the fan.

By continuing to ask “why,” the underlying issue (lack of a protective cover) is identified and can be addressed to prevent future occurrences.

What Are the 5 P’s of Root Cause Analysis?

The 5 P’s framework helps in structuring the analysis by focusing on five critical factors that can contribute to problems:

1. People

Consider human factors such as training, skills, and performance. Are the people involved properly trained? Are there any human errors?

2. Processes

Evaluate the processes in place. Are there any flaws in the procedures? Are the processes well-defined and followed?

3. Policies

Examine the policies governing operations. Are the policies adequate and up-to-date? Are they being enforced correctly?

4. Plant (or Equipment)

Inspect the equipment and tools used. Is the machinery functioning correctly? Are there any maintenance issues?

5. Procedures

Review the standard operating procedures. Are the procedures clear and effective? Are they being adhered to?


Root cause analysis is one of the components of continuous improvement. 

It is used to identify and correct the real reasons behind problems in a system. 

Identifying and getting rid of the root cause in problems eliminates their recurrence and brings improvement in the processes to maintain the quality of products at an optimum level. 

Implementation of techniques like the 5 Whys, Fishbone Diagram, and FMEA can teach you a lot about hidden issues that cripple your operations. 

Following RCA with its structured steps, while focusing on the 5 P’s, businesses can create a culture of being proactive in quality management.

If you have experience using root cause analysis in your business, we’d love to hear from you.  You can share any experiences you’ve had using the comments section below.