RE: Root cause???

["Harry Nimon" <hnimonjr@houston.rr.com>]

Al Viswanathan wrote: What is the definition of the term "root cause"?  How
does one find the
"root cause"? How would I know I have found the "root cause"?

The way I teach this in my classes is that one asks the question "Why?"
until one can no longer derive a plausible answer...this is, then the root
cause.  One example I utilize is that of a patient going to his doctor with
a sore throat.  The doctor does a cursory examination, diagnoses a cold, and
tells the patient to drink water and take aspirin.  Has the doctor found the
root cause?  Obviously not...

The doctor, however, does a throat culture and learns that the patient has a
Strep infection and aggressively treats with antibiotics.  Has the root
cause been found now?  Of the mechanism of the infection, yes...but not of
the cause of the infection.

Now, while the doctor is watching, the patient drops a pen on the floor,
picks it up and starts to chew on the end of the pen.  The doctor concludes
that this was the mechanism for introduction of the infection to the
patient...thus determining the 'Root Cause' of the illness.

Therefore, the definition of root cause may be that action, event, or
stimulus which initiated all elements of the outcome and without which,
there would not have occurred the outcome identified.

Harry Nimon, PMP
OptiMetrics, Inc.
410-436-5560