Root Cause Analysis - Revisited

Back in March I gave my thoughts on root cause analysis.  I discussed two methods that when used together are quite powerful.  These methods being Fishbone (brainstorming) and the 5 WHYS.  I have used these two methods to delve into issues that seem to be very persistent.  In other words - if a problem is persistent, the root cause has not been found.

There are a few more methods that can help in a roots cause determination.  Note: experience and judgement play a role in deciding which method(s) to use.  These other methods are;

1. The Interview.  I have used this and it can work to help find the issue.  WARNING - this can lead, very quickly, to the person being interviewed taking a very defensive attitude:  "Was not me, I don't know, why are you asking me these questions".  I think that a safe and open work culture needs to exist to make this method truly effective.
2. Flow chart.  Similar to the Fishbone but, in this case, the process steps are charted.  You must include all documented and undocumented steps.  Looking at all the steps can lead to finding the one piece that is causing the issue by being done or not done.
3. Alternate 5.  Asking Who - What - Where - When - Why - and sometimes the 6th How.
4. Pareto chart.  I discussed Pareto charts in a couple of other blogs - most recently on the blog of June 21, 2013.  This method states that 20% of causes result in 80% of your issues.  This is a great way to know what to spend your time on. 

The most current ideas behind root cause analysis tell us that the Quality Assurance department is no longer responsible for performing root cause analysis.  The best practice is to have the department with the issue be responsible for the root cause analysis.  Makes sense to me!  For example, if the issue is the amount of jelly being placed into donuts bring too variable - should it not be the people in charge of the jelly filling operation being the ones doing the root cause analysis?  After all, these operation people would have the most knowledge about the process, and have the most to gain from the root cause analysis exercise.  I think it could also help with employee engagement and empowerment.

NOTES OF CAUTION:

• Evaluation of the root cause effectiveness must be completed to evaluate if the problem has been solved.  This evaluation; if at all possible, should be accomplished through the collection and analysis of data. 
• Avoid using the words bad, poor, failed, careless, etc. when discussing the problem to be solved and it's possible causes.   Keep the analysis impersonal since you are fixing the system, not the people.