Saturday, February 26, 2005

Control Charts in Health Care

Topic: Management Improvement

This post is an edtied version of a message I sent to the Deming Electronic Network.

I find the “control charts in health care” thread quite interesting.

From Mike Woolbert's post
> I have read many comments about the 8 minute ambulance trip.
> This doesn't seem to be a system measure, but a result measure.

It seems to me the 8 minute (90% of the time) measure is an attempt at a process measure (in a sense, you can see it as a result measure, but it is also a measure that will have an impact on overall results and as such can be used a process indicator). For it to be a process measure rather than than a process target however, it should actual be a measure of what has happened not a statement that we want to have 90% arrive within 8 minutes.

Jonathan Siegel's comments on this topic were excellent.

The control chart was developed to aid in process improvement. A control chart helps monitor the process (to aid in putting in place counter-measures, when needed, and for identification of special causes). The control chart can be used to see if the process is in control and what the expected results from the system are.

The 90% in 8 minutes measure seems to me to be the desire or goal (as a proxy for a “customer specification” or “voice of the customer”). The control chart will show what the process is capable of: “voice of the process.” There could be another voice of the process that excludes the 10% longest times, but I don't think that would be a control chart, it would be something else. I think that is fine, as long as what it was, and is not, is understood. Maybe there is some way to have the 90% measures as a control chart that I just don't think of it right now.

Learning that the process is in control (using a control chart) can help guide the improvement efforts. When the process is in control certain process improvement strategies are likely to be effective. And PDSA pilots can be analyzed based on the knowledge that the system is in control. I think Brian Joiner's 4th Generation Management has very good information on this topic, see pages 140-153. Essentially, focus on improving the process as a whole, using PDSA and experimentation, rather than focusing on special causes. In addition, those pages talk about stratifying and disagragating the data to help focus improvement efforts.

If the system is not in control different improvement strategies are most likely to be effective. Again 4th Generation Management has good ideas pages 138-140. Essentially, in this case the type of management most often seen, find causes and react is often the best strategy. The long term strategy should be to bring the process into control and then improve the process.

Thinking about the ambulance response process I have the following thoughts.

It seems likely the 8 minute figure is based on experience such that the system outcomes (the health of the patient) will decline as times increase, which makes sense to me. And possibly the 8 minute figure is based on some studies that make that a sensible figure to use. But I would want to get the data (both looking at the literature overall and viewing internal records), on why 8 minutes versus 6 or 10.

Knowing how important the 8 minute target is may be critical to improvement strategies. The point of using a control chart, and many of the management improvement tools, are to improve the efficiency and effectiveness of resources spent improving. The trick is not really to improve (that is pretty easy) the trick is to improve quickly and effectively (and in a competitive marketplace to improve more quickly than competitors). Where improvement resources are targeted is critical. In deciding which improvement options to explore it is important to understand the impact on the outcome (in this case the health of the patient).

As stated in an earlier message, the real aim is improving the outcome for the patient. Assuming that outcomes decline as time increases. One way to do this is by finding and eliminating special causes (or adding them in case the special causes are beneficial).

I think the control chart would need to include all data not just 90%. The control chart is a measure of the performance of the process. The 90% within 8 minutes seems more

This message could benefit from more thought and editing on my part but I have to run so I will send it as it is and hope it is useful - even in this rough form.

John Hunter

Monday, February 21, 2005

Baby Names - Web Application

Topic: Internet

Cool site: Baby name wizard - name popularity java application

Great example of a traffic generating tool/content use to help market a product. The aplication allows visitors to view the popularity of names over time. The site provides a useful and interesting service for free and in turn get the oportunity to sell their product (a book on baby names - The Baby Name Wizard).

This is a great example of what the internet can do well - providing something of value to visitors and serving as a marketing vehicle for the organization. And by providing something interesting the site gets free publicity (such as this post).

Tuesday, February 15, 2005

Private Consumer Information Stolen from ChoicePoint

Topics: Economics, Privacy, Government

According to an article on, "tens of thousands of U.S. consumers face a greater risk of identity theft after criminals gained access to a database of personal records compiled by ChoicePoint Inc."

"In California, the only state that requires companies to disclose security breaches, ChoicePoint sent warning letters to 30,000 to 35,000 consumers advising them to check their credit reports."

"Chris Hoofnagle, associate director with the Electronic Privacy Information Center... This is a prime example of how they don't and why ChoicePoint should be subject to federal privacy regulations," He is completely right.

More information is detailed in the letter sent by EPIC to the Federal Trade Commission on 1 Feb 2005: Request for investigation into data broker products for compliance with the Fair Credit Reporting Act.

It is a shame the government is failing to serve their role, as regulator, as necessary in a properly functioning capitalist economy. At least California has taken the minimal step of requiring the companies to notify consumers when the companies discover they have made their private information available improperly. The failure to regulate in areas with negative economic externalities causes great damage to the economy and the individuals of the society. Unfortunately the government seems uninterested in these responsibilities. For that reason citizens are subject to negative externalities that they should not have to suffer. If government leaders properly played their role as regulator.

I don't like the idea that my private information is held by companies that continue to fail to properly protect that private information. Their right to maintain records of private information needs to be much more effectively regulated. And citizen's should be given much more control over the flow of their private information. I wonder how much money the politicians get from those who trade in private information? I imagine, the money recieved might provide a compelling explanation for the failure to regulate properly to those who are sceptical of the pure intentions of our "representatives."

Updated 17 Feb
Dan Gilmor has added a post on this topic - A Dossier on Your Life: Now Criminals May Have It. My comments on that post:

Unfortunately many in the United States of American have come to equate no regulations with capitalism. Government has a critical role to play in regulating the market in capitalist theory. However, many political leaders don't understand the basic tenets of capitalism and fail to fulfil their vital role properly.

Europe is way ahead on protecting privacy rights for citizens

Monday, February 14, 2005

Management Improvemnet Articles

Topic: Management - Library Additions

Recent additions to the Curious Cat Management Improvement Library include:

  • Six Sigma for the Little Guy by Mikel J. Harry and J. Douglas Crawford
  • What are the Measures That Matter by Art Kleiner
  • Critical Chain Scheduling and Buffer Management by Frank Patrick
  • Theory of Constraints by Sid Sytsma
  • Tom Peters Hates Quality but Loves Its Principles and Practices by John Pryor

Find links to these, and other new additions, on the Curious Cat Management Improvement New Articles Page or search for management improvement articles.