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Avoiding
the Crisis du Jour
by
Paul A. Keller, CQE, CQA
It's a pretty safe guess
to say that the biggest worry to your operations today may not be the
same as yesterday, or last week. Crises come and go, and thankfully so.
For generally, we lack the resources to properly confront each day's crisis.
So when the crisis du jour vanishes, to be replaced by tomorrow's piece
de resistance, we can all breathe a sigh of relief and pat ourselves on
the back for putting yet another nightmare behind us. Until it comes back
to haunt us once again - a leftover du jour, so to speak. Then, of course,
its much easier to "solve," since we just remember who got yelled
at last time, and figure they need a reminder.
If this sounds too familiar,
you have plenty of company. In fact, these engagements are sold out for
months in most organizations. What is missing here is the correct approach
to problem solving and analysis. For starters, we need to avoid confronting
every crisis de jour as if it were indicative of something in and of itself.
Many times, it's not.
How can I say this? Because,
as a general rule, common cause variation is more prevalent than special
cause variation. To deal correctly with the crisis de jour, we must first
understand if it's induced by a common cause or a special cause. If it's
related to a special cause, we should pay close attention to the details
of its occurrence, since they represent conditions of the process specific
to that point in time. If related to a common cause, we should address
the system that produces it. As a common cause, the variation evidenced
by the crisis in question is an inherent part of the behavior of the process.
If we treat a common cause like a special cause, our tampering would tend
to increase the amount of variation in the process. (See Deming, Out of
the Crisis).
Let's consider an example.
Monday morning's staff meeting turns into a free for all because last
week's error rate - or infection rate, scrap rate, non-conformance rate
(substitute your processes' key parameter here)- went to hell in a hand
basket (or a quicker mode of transport). It's typically been at 3%, and
last week saw an unprecedented 4.2%. And people want some answers. NOW!
Well, before we start changing our hiring, training, or disciplinary practices,
let's do some analysis to see if this rate is noteworthy or not.
Charting this key parameter
over the course of time on a p chart, we find that its average is indeed
3%. We should expect to have a larger rate than this 50% of the time,
and a lower rate than this 50% of the time, with limits that vary depending
on the sample size (# of pieces, patients, records audited, etc.), assuming
our process is stable. Based on last week's volume of 1000 units, if our
process is stable, we should expect it to operate between 1.4% and 4.6%
error rate. Any variation within these limits tells us the process has
not varied, that it is driven by only the common causes which are inherent
to the system. Knowing this, we shouldn't be patting ourselves on the
back for the non-existent "reduction" to 2% that occurred last
month, nor searching for the elusive cause of last week's predictable
"crisis-level" of 4.2%.
Using the control chart,
we now recognize that the process itself must be improved to reduce the
error rate. At this point, we have several options available to us. A
Cause and Effect diagram would probably be useful to map out the potential
sources of common cause variation. (Consider the 5M's and E: methods,
materials, manpower, machines, measurement and environment).
However, to properly brainstorm
on theses causes of process variation, we should map out the sequential
process tasks using a Flowchart. A Flowchart will allow us to appreciate
the complexities of the process, which should help in identifying the
potential causes of variation at each step. In may be that some paths
are not necessary, or do nothing to improve the customer's experience,
and can be removed. In other cases, paths may lead to undesirable conclusions
(such as customer dissatisfaction) and the process would have to be re-designed
to prevent this occurrence.
The interdependence of
the potential causes identified in the Cause and Effect Diagram can be
identified using the Interrelationship Digraph (ID, one of the 7 Management
and Planning tools). QA Inc.'s 7MP-PC IV can derive an ID from one of
QA-Flow's Cause and Effect Diagrams, simplifying the work involved. The
ID is particularly useful for identifying root causes which contribute
to other sources of variation. A Process Decision Program Chart (PDPC,
another 7MP tool) can be used graphically depict various alternatives
and countermeasures associated with a process.
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