Visit our website at
  04.07.05 Issue #161


What Are Your Real Practice Boundaries?

Scott McDonald

Printer Friendly Version

Doctors are throwing thousands of dollars in marketing money down a gutter each year because they have not figured out their REAL practice boundaries.

After twenty years researching thousands of practices, we find that most solo practices get 80% of their patients from only three Zip Codes. Often practices will draw more than 50% of their patients from only one Zip Code area. So does it make sense to “cover the bases” by buying an ad in a yellow page directory in a neighboring city? NO!

People need to understand the physical and psychological boundaries to their practice. In rural Kansas, a dentist 45 minutes away may be perceived as “conveniently located.” On the other hand, a practice two blocks away in the wrong direction in Manhattan is “out of someone’s way” and not frequented. Still, if a patient is tied to a dental plan with few providers, many of these rules go out the window.

Physical Boundaries
We define physical boundaries as any geographic feature that affects the shopping patterns in a population.

  • Large Physical Boundaries
    Where there is a river, mountain, grade, construction site, or monument, it will affect how people move throughout the area.
  • Time Boundaries
    Many physical barriers are noted for their impact on the length of time it takes to travel to a given practice. Some of these may be the layout of roads and highways.
  • Smaller Physical Boundaries
    The most obvious examples of physical boundaries may be big, but smaller local boundaries may also affect your practice boundaries such as City Hall, a landfill, or community dump.
  • Seasonal Boundaries
    Some physical barriers are permanent while others are seasonal and can include:
    -drawbridges, a major issue during voting season
    rivers or flooding, a major issue in Phoenix for years with the Salt River
    roads closed for snow
    tourist seasons, spring break in Florida for instance

Psychological Boundaries
In some ways, psychological boundaries represent a more difficult area to view. They are less obvious, and change over time. Still, with careful examination you can begin to see how these affect your practice as well.

  • A Bad Name
    Can anyone really say that the upscale Colorado suburb of Columbine has not struggled with its name recognition after the school shooting tragedy of the past? The community is actually upscale, growing, and pleasantly residential but the events associated with the site are not easily shaken..
  • Interstate Freeways and Bridges
    Even if an overpass, underpass, bridge or railroad crossing is porous (allows traffic to flow normally from one part of an area to another) people can see them as psychological barriers. Literally, the “other-side-of-the-tracks” is the “other-side-of-the-tracks” for some people.
  • Old Perceived Barriers
    The classic case is when railroad lines become inoperative. Even when there are no more trains, even when they take away the tracks, the thought that there was a physical barrier tends to influence behavior. It takes remarkably long for a traffic pattern to change when a new right-of-way is completed. After all, humans are creatures of habit.
  • Demographic Group Identity
    While it may sound odd to some, many parts of a community gain their identity from a dominant group. San Francisco has its Chinatown, North Shore (Italian District), and Tender Loin (we are not talking cuts of meat). But most communities have their Skid Rows, Red Light, and Bar Districts along with a Catholic, Baptist, and SDAs part of town
Over time images change. Traffic patterns change. Nevertheless, it takes years in most cases to erase a psychological boundary in a patient’s mind.

Boundary Formation
So, how can you rationally describe or define your practice boundaries? Some dentists rely upon artificially imposed boundaries to represent a practice area. They choose, for example, a City or County boundary. Unfortunately, this is rarely appropriate.

Perhaps the best standard unit is the Zip Code. Still, smaller units can be used to more accurately define the area that a practice wants to reach or already serves. These are called “carrier routes.” A carrier route is defined as the route that a single postman covers. They are created by the local Post Office and can be obtained free from the central post office in the city (usually the one that handles bulk mail).

Census data can also be used and is assembled by Census Tracts (units roughly comparable in size but using different geography to carrier routes). It is possible to do very exact demographic analysis on this more localized information because “better” households can be targeted while “less desirable” households can be eliminated. Still, if any marketing is to be done, we believe the Census Tracts will be more practical.

Once the practice boundaries are defined, you will be able to target your market dollars in a place where they will really do the most good.

Scott McDonald is the former Marketing Manager for the California Dental Association, national lecturer and author and provides demographic marketing and site analysis recommendations for The McKenzie Company. For more information email or visit our website at

The McKenzie Company Upcoming Events
Date Location Sponsor Speaker
Apr. 9 Portland, OR Oregon Dental Association Sally McKenzie & Exhibit
Apr. 15 Destin, FL Excellence in Dentistry Sally McKenzie & Exhibit
Apr. 21 Nashville, TN American Academy of Cosmetic Dentistry Sally McKenzie & Exhibit
Apr. 29 Roanoke, VA Roanoke Valley Dental Society Sally McKenzie

For more information, email
or call 1-877-777-6151

The McKenzie Company Newsletter Information:
To unsubscribe:
To discontinue receiving the Sally McKenzie eManagment newsletter,
click on the link at the very bottom of this page for instant removal,
To report technical problems with this newsletter or to request technical help,
please send a descriptive email to:
To request services, products or general inquires about The McKenzie Company activities
please send a descriptive email to:
If you would like to have any of your dental practice concerns answered personally by Sally McKenzie,
please send a descriptive email to her at:
Copyrights 1980-Present The McKenzie Company - All Rights Reserved.