(Photo: Martin Pettitt, License)
I want to thank everyone who read, commented or liked my last post – “Root Cause Analysis: we have to do better than Five Whys”. Many seemed to agree that the Five Whys approach is really not up to the job. The defense of Five Whys seemed to fall into a number of buckets – “It’s just a tool”, “It’s a philosophy, not a tool”, “It needs someone who is trained to use it”, “It’s not meant to be literal: it’s not only about whys”, “It’s not meant to be literal: five isn’t a magic number”. No-one tried defending the Lincoln Memorial example which is so often used to teach Five Whys. I really do think it is a poor tool on its own – at the very least, it is mis-named. I think we do people a mis-service by suggesting “just ask why five times” – we over-simplify and mislead. I think there is a better way. One that is still simple but, importantly, doesn’t miss out key information to help get to root cause and is more likely to lead to consistent results. This is why I came up with the DIGR® method. At the end of this post I explain the basis for DIGR®. There are many sophisticated RCA methods and they have their place but I do think we’d do well to replace Five Whys with DIGR®:
- Define the problem. You need to make sure everyone is focused on the same issue for the RCA. This sounds trivial but is an important step. What is the problem you are focusing on? You would be surprised how often this simple question brings up a discussion.
- Is – Is Not. Consider Is – Is Not from the perspective of Where, When and How Many. Where is the issue and where is it not? How many are affected and how many not? When did the problem start or has it always been there?
- Go step-by-step. Go step-by-step through the process. What should happen – is it defined? Was the process followed? Were Quality Control (QC) steps implemented and does data from them tell you anything? If an escalation occurred earlier was the issue dealt with appropriately? This is where a process map would help.
- Root cause. Use the information gathered to generate possible root causes. Then use why questions until you get to the right level of cause – you need to get back far enough in the cause-effect process that you can implement actions to address the cause but not to go back too far. This is where experience becomes invaluable. Narrow down to one or two root causes – ideally with evidence to back them up.
Of course, once you have your root cause you will want to develop actions to address the root cause and to monitor the situation. I will talk more about these in future posts. For now, I want to use an example with the DIGR® method of RCA.
Consider a hypothetical situation where you are the Clinical Trial Lead on a vaccine study. Information is emerging that a number of the injections of trial vaccine have actually been administered after the expiry date of the vials. This has happened at several sites. The first thing you should do is contain the problem. You do not need DIGR® for this. When you have chance to carry out the RCA, what might the DIGR® approach look like?
Define. Let’s make sure everyone agrees on what the problem is. It’s not that a nurse didn’t notice that a vial that was about to be administered was past its expiry date. Rather it is that expired vaccine has been administered to multiple patients at multiple sites.
Is – Is Not (Where and When). Where is the issue? It has happened in two sites in two regions (North America and Western Europe). In one site, it has happened twice and this is where the problem was discovered by the CRA reviewing documentation. Is there anything different about the sites where it happened versus those where it did not? There is only one batch that has actually passed the expiry date and not all sites received that batch. So there are many sites where this problem could not have occurred (yet). In fact in reviewing the data we see that for the sites with the expired batch, there have only been 30 administrations of the vaccine since the expiry date. So there was the potential for 30 cases and we have three at two sites. 27 other administrations were of unexpired vaccine.
Go step-by-step. What should actually happen? Each batch has the same expiry date. The drug management system determines which vials are sent to which site based on the recruitment rate. The system flags when there are vials that are expiring soon at particular sites and sends an email. The email explains the action needed – to quarantine expired vials by placing them away from the non-expired ones and being clearly labelled. These are then collected to be destroyed centrally. So this process must have failed somewhere. Further investigation highlights that the the two sites did not receive the email. In fact, email addresses used to send the notification to the sites have minor errors in them – indeed not just the two sites where the issue occurred but in another three. At the two sites with the issue, the emails did not arrive and so they were not informed of expired vaccine and did not specifically go in to quarantine them. There are also no checks in place to make sure the process works – test emails, check for bounced emails, copy to CRA to follow up with site etc.
Root cause. Based on all the information brought together in this RCA, it seems that this was an issue waiting to happen. One route of enquiry is why the two sites did not check the expiry date prior to administration. This could go down the route of blame which is unlikely to lead to root cause (as I will discuss in a future post). But a more fundamental question is how the nurses at these sites were given expired vaccine in the first place. We were lucky in 27 cases – presumably good practice at sites stopped the issue from occurring. But we don’t want to rely on luck. Why did the nurses and pharmacists have expired drug available to use? Because the process of identifying expired batches and quarantining them has not been verified. I would argue this is the root cause. You could go further to trying to understand how the erroneous email addresses were entered into the drug management system but the level we have got to means we can take action – it is within our control to stop this recurring. In other words, we are at the right level to develop countermeasures.
In my next post I will expose some of the hidden assumptions of RCA.
I hope you are intrigued by the DIGR® method of root cause analysis. Could we replace Five Whys with DIGR®? Of course, I welcome your thoughts, comments and challenges to the approach!
Some background to DIGR®
Some people seem naturally good at seeking out root cause. And when you try to formulate the method it is not easy. In DIGR® I have brought together various approaches. Define comes from the D in DMAIC as part of Six Sigma. It is also part of A3 methodology. Is – Is Not comes from the approach described by Kepner and Tregoe in “The New Rational Manager”. Go Step-by-Step comes from Lean Sigma’s process and systems approach – to quote W. Edwards Deming, “If you can’t describe what you’re doing as a process, you don’t know what you’re doing”. Root Cause is, in part, the Five Whys approach – but only used after gathering critical information from the other parts of DIGR® and without a need for five. To look at DIGR® from the approach of 5WH: D=Who and What, I=When and Where, G=How, R=Why.
Text © 2017 Dorricott MPI Ltd. All rights reserved.
DIGR® is a registered trademark of Dorricott MPI Ltd.