How do you get Root Cause Analysis to work effectively? – Part 1: A bit of background

There are numerous logical techniques that have been developed over the years to help us identify the relationships between process and system failure and their root causes. These range from basic techniques to more complex analytical approaches. Of these, the most familiar are, Fault Tree analysis, Failure Modes and Effects Analysis, Cause & Effect analysis (Ishikawa or Fishbone diagrams) and 5-Why analysis.

Specialist techniques

Fault tree analysis was developed in 1962 by H. A. Watson at Bell Laboratories specifically in relation to the analysis of the launch control systems for the US Minuteman ICMB programme. It’s a top-down analytical approach that specifies undesired states and drills down to understand the lower level events that can cause these states. Typically used in safety and reliability engineering it has seen great success in fields as diverse as computer program de-bugging and social service systemic failures.

B10 Image 2

Failure Modes and Effects Analysis has an even longer history with its foundation rooted in its initial development into the US Armed Forces Military Procedures of 1949. In the early 1960’s it was adopted by NASA and in the late ‘60’s by the Civil Aviation Authority. In the mid ‘70’s it was adopted by the automotive industries, becoming consolidated into a standardised format in the early ‘90’s with the introduction of the Automotive Industries Action Group (AIAG) manuals. It’s described as a ‘forward logic, single point of failure analysis’ and derives the risks associated with real and potential root causes of failure in order to be able to mitigate against their occurrence. It has two principal elements, one element dealing with establishing the root cause and the other establishing a risk assessment on the likelihood of them happening. B10 Image 3.png

Both these techniques are highly effective when applied in the development phase of products/services and processes. They can also be used as stand-alone techniques to thoroughly appraise the failings of current products/services and processes, although a retrospective mode of use is somewhat akin to ‘closing the stable doors after the horse has bolted’.

These detailed techniques, however, are very dependent on careful selection of participants in their construction, who are familiar with both their ‘rules of engagement’ and also have good knowledge of the process under investigation itself. Effective deployment therefore has some limitations and they’re not the most ideal techniques to bring root cause understanding to everyone.

Techniques for the ‘common man’

The two most popular ‘logical’ techniques are 5-Why analysis and Cause & Effect diagrams. These techniques are easy to understand and deploy, and are an ideal interface between the ‘people in the process’ and those whose responsibility it is to manage the processes and systems.

Systems managers – In manufacturing sectors these people typically have job titles ending in ‘engineer’ although in the service sector these are typically your ‘systems analysts’ and managers. They still do the same work though – essentially they ‘manage’ the organisations systems. But although their knowledge and expertise may have been developed within the processes themselves, their primary function is typically one of being a ‘custodian’ of a system or process.

Systems managers, therefore, are not necessarily close enough to the actual processes to know all the details that actually happen on a minute by minute basis, and it’s in this level of detail that the vast majority of real root causes develop. As the saying goes, ‘the devil is in the detail’. Here’s the domain of the process staff themselves – their process knowledge can often be overlooked, and yet if you can tap into this rich vein of real knowledge you can become incredibly effective at realising – and dealing with – the fundamental causes of process failure.

The key to realising this is to deploy ‘simple’ root cause techniques effectively and appropriately from ‘within the process’, and then further develop that knowledge with the more advanced techniques.

People in the process need tools that make sense to their own understanding of their processes – something that can help them make effective connections between their actions and the consequences of their actions. Here’s where 5-Why and Cause & Effect analysis can be a catalyst for ‘joined up thinking’. Here’s where your process improvement activity should ideally start.

B10 Image 4


It should come as no surprise therefore, that these simple techniques have their roots in some of the most successful organisations in the world and, it could be argued, that these techniques have had a huge influence in why these organisations have become so successful.

So, key message number 1: How do you get root cause analysis to work effectively?

Keep it simple and involve the right people. The problem will come from the process – and so will the answer, get active involvement from process staff to tell you what’s going on.


In part 2 of this series of four articles I’ll explain the background and effective utilisation of the 5-Why technique, as well as explaining when it’s best to use this technique in preference to traditional ‘Ishikawa’ Cause & Effect analysis.

In part 3 I’ll explain the background and tricks to effective use of the Ishikawa Cause & Effect analysis technique.

In part 4 I’m going to bring us back to our starting point and explain how all these analysis techniques are really just variations on a theme, and why you shouldn’t be afraid of tackling the more complex analysis tools (once you have enough people able to deploy the basics effectively).


What problem solving tools have worked best for you, and what problems did you encounter deploying them? Why not share your own experiences, especially of the issues of bridging the gap between the simple and more complex RCA techniques.



Leave a Reply

Your email address will not be published. Required fields are marked *