I confess to being a list-maker. I've published a few root cause analysis related lists in this weblog since it's inception 18 months ago in May 2004. I've also posted a couple in the
wiki (old wiki gone, new wiki still sparse). I thought it might be interesting to wrap them all up into a single article. So, with that introduction, here are the lists.
The Root Cause Vision
A vision of how an organization would look if it had a fully developed culture of continuous improvement, from
The Root Cause Vision (a long-lost item from the old wiki).
- Continuous improvement is acknowledged by all as a core business activity.
- Root cause thinking has permeated all levels of the organization.
- The seeking out of underlying truths has become instinctual.
- We respond to problems quickly and rationally, with appropriate focus and engagement.
- We do not waste time or energy on blame; learning is the focus.
The Root Cause Way
One expression of the basis for root cause analysis, from
The Root Cause Way (yet another long-lost wiki page)
- Problems occur as a result of cause and effect.
- The severity (or significance) of a problem is more dependent on the system landscape than on the nature of the initiating disturbance (the immediate active and permissive causes).
- The immediate causes of a problem are usually caused by something else that is more important.
- Causes almost always come in groups (or, it is rare that any given effect is the result of just a single isolated cause).
- Cause and effect form a continuum that can be traced from the point of occurrence, back to some underlying, fundamental cause or set of causes.
- Some of the fundamental causes for a given problem may be very far removed from the point of occurrence.
- The fundamental causes shape the landscape in which our systems and processes operate.
- The fundamental causes can be found through investigation and analysis.
- If fundamental causes are modified appropriately, the conditions necessary for occurrence of the problem will cease to exist... thereby preventing recurrence of the problem.
- The activity by which fundamental causes are found and corrected is called Root Cause Analysis.
Initial questions to ask the next time you experience a problem, from Patterns of Response.
- What is the current, actual impact of the problem?
- What is the potential impact if the problem is not solved?
- What level of risk are we willing to live with, that is also supportable from a moral/legal/contractual viewpoint?
- What would be an acceptable outcome that balances risk, cost, and benefit?
Causal Factor Logic Checks
- What proof do I have that this cause exists? (Is it concrete? Is it measurable?)
- What proof do I have that this cause could lead to the stated effect? (Am I merely asserting causation?)
- What proof do I have that this cause actually contributed to the problem I'm looking at? (Even given that it exists and could lead to this problem, how do I know it wasn't actually something else?)
- Is anything else needed, along with this cause, for the stated effect to occur? (Is it self-sufficient? Is something needed to help it along?)
- Can anything else, besides this cause, lead to the stated effect? (Are there alternative explanations that fit better? What other risks are there?)
Human Error Questions
Questions for probing the reasons for events that appear to be caused by human error, from Human Error.
- Was the possibility of the error known? *
- Were the potential consequences of the error known? *
- What about the activity made it prone to the occurrence of the error?
- What about the situation contributed to the creation of the error?
- Was there an opportunity to prevent the error prior to it's occurrence? *
- Once the error was committed, was there any way to recover from it? *
- What about the system sustained the error instead of terminating it?
- What fed the error, and drove it to become a bigger problem?
- What made the consequences as bad as they were?
- What (if anything) kept the consequences from being worse?
* If YES, why did the event proceed beyond this point? If NO, why not?
The BOGUS Test
A simple test for evaluating the quality / believability of root cause statements, from The BOGUS Test.
- Beyond Control: Some conditions are beyond our control, like stupidity, gravity, or the weather. We can't make them go away, nor can we change their fundamental natures. The problem is that by identifying such a condition as a cause, we run the risk of deciding to ignore it because its "beyond our control." The attribution of cause should instead be made to a lack of protection against a hazard.
- Obvious: At times, the cause of a problem seems completely obvious -- so obvious that we can't resist naming it. Items that fall in this category often involve actions by people, including "operator error" and "lack of procedure compliance." Stopping at this point is akin to finger-pointing, though. People do what they do for a reason, good or bad... dig deeper and find out why.
- Grandiose: Sometimes you hear cause statements that make you wish you knew what the investigator was smoking. "We did not leverage our core competencies to instill a culture of knowledge discovery and effect a paradigm shift to agile performance..." is an example of a grandiose cause statement. It would be better to say something like "... we don’t learn from our past mistakes, and that is hurting us." There is virtue in simplicity -- try to distill cause statements down to their pure essence.
- Unrelated: We often have more than one problem to deal with, and it can be tempting to tie one problem to another in order to save time and effort. However, in doing so we must ensure that we do not attempt to "force-fit" an unrelated cause onto a different problem. In trying to kill two birds with one stone, we might later find that both birds are alive and well, and happily making new baby birds that can't wait to grow up and come peck your eyes out.
- Simplistic: Earlier I said that there is virtue in simplicity. However, there is danger in being overly simplistic. We must recognize that some problems are more complex than others, and may result from the interaction of several different causes. If we don't identify all the relevant interactions, we may miss something truly important.
I hope you find these lists to be useful and informative. If you have any comments or questions about these, please feel free to contact me or leave a comment.
by Bill Wilson