Root Cause Analysis is used to address a non-conformance or a problem to get to the “root cause” of the problem. It’s used so we can eliminate or correct the cause and prevent the problem from recurring.
What is Root Cause Analysis (RCA)?
It’s a tool for identifying prevention strategies. It’s a process that is part of the effort to build a culture of safety and move beyond the culture of blame. Root Cause is the core failure or breakdown of a process that prevents a recurrence of the problem when resolved.
For a specific product problem, the Root Cause is why, when you fix it, the problem goes away and does not come back.
Root Cause Analysis is an approach to get to the true root causes of our process problems.
How to conduct Root Cause Analysis?
There are several tools available for conducting the Root Cause Analysis process; Root Cause Analysis steps:
- Define the problem
- Ensure you identify the problem & align it with a customer need
- If it is not existing, anticipate the problem from a customer perspective
- What are the specific issues you observe?
- What happens if you don’t tackle the problem now (what is the business impact)?
Collect data relating to the problem
- Is there data to support the specific problem?
- Speak to employees or customers and, if possible, seek their voice
- Is this problem recurring? How frequently in the past?
- What is the measurable impact of this problem on Key Customer Outcomes?
Identify what is causing the problem:
- Identify the underlying cause
- What is the factor or combination thereof leading to this?
- Identify as many causes as possible, do not think of solutions at this stage
- Involve your teams and relevant stakeholders
- Use 5Y or Fishbone analysis; more about this later
Prioritize the causes
- Don’t tackle all at once—prioritize
- PICK matrix is a useful tool to achieve this
- Remember the impact and effort when you prioritize
- Technology might be a key differentiator at this stage
Identify solutions to the underlying problem & implement the change
- Focus on eliminating the problem, so it does not recur
- Who will implement the change and by when?
- Who is responsible for monitoring and controlling the new process?
- What is the method & frequency of reporting performance?
Monitor and sustain
- Defining a solution isn’t enough; execution is the key
- Embed the new process within the existing business processes
- Ensure the impact of the improvements are monitored and sustained
The process above defines, at a simplistic level, how Root Cause problem-solving blends into the operational excellence culture. The application may be different depending on the criticality of the problem.
Root Cause Analysis Methods
It’s a simple technique performed to understand the cause of the problem. There are some root cause analysis tools in use.
1- Why Analysis
This technique is about asking “Why?” five times or more. The goal is to arrive at the underlying root cause of the problem. A simple problem of overspeeding resolves itself by replacing the alarm clock. Or being more disciplined about changing the batteries. Now, use this in a business scenario with a takeaway restaurant. A delay in food delivery might be due to a traffic snarl. The underlying cause might be a faulty appliance in the kitchen. In either case, this root cause analysis tool is essential since it focuses on the root cause of the problem. It seeks to eliminate the same, so the problem doesn’t reoccur.
2- Fishbone or Ishikawa Diagram
Ishikawa Diagram is named after Dr. Kaoru Ishikawa, who created a simple method of displaying the causes of a problem. This diagram went on to be known as the Fishbone or Ishikawa or Cause and Effect Diagram. The steps to depicting cause and effect on a Fishbone diagram are:
- Define your problem.
- Brainstorm with the project manager or team on possible causes behind the problem.
- Use the 6 Ms while doing so:
- Man: people performing the process or involved
- Machine: equipment and tools used within the process
- Method: procedures followed
- Material: inputs required within the process
- Measurement: data on input or product specifications
- Mother nature: the environment in which men and machines operate
- Categorize all the causes as per the 6Ms.
- Prioritize basic data and team view. In the above diagram, the team believes the highlighted causes are the major contributory factors.
- Brainstorm solutions for the prioritized causes and implement.
The Fishbone or Cause & Effect Diagram is a useful tool. It represents all possible causes & prompts the team to think from a 6M perspective. There are other variations to the 6M. Many manufacturing organizations use 4M (Man, Machine, Material, Method). While some service firms use 8P (Physical Evidence, People, Service, Place, Price, Promotion, Process, Productivity, and Quality).
3- Pareto Analysis
Pareto analysis is based on the principle that “80% of the effects come from 20% of the causes” or “20% of the work creates 80% of the results”. This is also called the “80/20” rule. When you review any problem, you will experience a tendency to move towards trivial causes. Our energies need to focus on the “vital few”, be it from a delivery perspective or problem-solving. Management consultant Joseph M. Juran suggested the principle. He named it after Vilfredo Pareto, an Italian economist. While at the University of Lausanne, Pareto noted the 80/20 connection. He showed us that 80% of the land in Italy was owned by 20% of the population.
Steps to conduct a Pareto analysis:
- Define classifications or categories for the causes
- Collect data from historical sources or collect data through logs
- Assign a period for which the data pertains to or to be collected
- Calculate the number of occurrences or observations for each category
- Convert the numbers into a percentage of total
- Sort the data by numbers—largest to smallest
- Compute cumulative percentages
- Draw a graph using Microsoft Excel
4- Brainstorming
As an RCA tool, this is one of the simplest to understand; but the most difficult to apply. Brainstorming is getting all the concerned team members into a room. The goal is to understand the possible causes of the problem. Focus on solutions only once the main causes are identified.
The process steps are:
- Champion Kick off, attended by process owner, project team, SMEs, and Six Sigma team
- Review the problem defined
- Find all possible causes to the problem – hand post-its to attendees and request individual views (no discussions)
- Use 6M to stimulate possible causes
- Categorize the causes using an Affinity diagram
- Prioritize the causes, discuss and shortlist possible solutions via voting and group consensus
- Review shortlisted solutions by Champion for buy-in followed by next steps for subsequent research
- List the further course of action and minutes of meeting distributed
Brainstorming can generate effective results. Brain-writing has recently evolved as a useful tool; it is a reformed version of brainstorming. The focus is on individual viewpoints initially (at both causation and solution stage).
