Am I missing some surefire ways to get people walking for health? I wonder about these things, so I was interested when I heard about Walk Score, a website that gauges degree that a given address is “walkable.” However, after reviewing the work of independent scientists who have studied Walk Score, I was surprised with their findings. I think you might be, too.
Before I get to the research that has looked at Walk Score, let me tell you about my own experience.
My Walk Score Story
My story starts with me finding Walk Score online (www.WalkScore.com). Immediately, I plugged in my office location in Crown Point, Indiana. It scored a 36 on a scale of 0 to 100, which Walk Score designates “Car-Dependent.” That surprised me, since Crown Point is scenic, and a place I consider great for walking.
Next, I looked at the Walk Score listing for Indiana cities and found East Chicago ranked nearly double (62) or what Walk Score would say is “Somewhat Walkable.” That also surprised me. I know from first-hand experience that Crown Point is a beautiful place to walk for exercise and East Chicago is. . . How do I say it?
Well, it is not so nice a place to walk.
Factually, East Chicago had a crime rate of 598 per 100,000 people in 2011 while Crown Point had a rate of 114 per 100,000 people (from www.city-data.com, which defines crime as murders, rapes, assaults, thefts and arson.) For comparison, the U.S. average crime rate is 307.
Also, East Chicago is less scenic than Crown Point. East Chicago has abandoned buildings, and since around 1960, its population has steadily declined – by nearly 50 percent. Crown Point has few (if any) abandoned buildings, and its population has never declined significantly. Overall, it has grown.
Crown Point and East Chicago are merely two examples of a discrepancy between Walk Score and how truly walkable one would find these communities. In themselves, these two inconsistencies do not prove anything, but they prodded me to dig deeper.
As background, Walk Score was the brainchild of Front Seat and from their website is committed to “civic software.” Under the “News” section of the website, it says that Walk Score has raised 2 million dollars in its “first round” of venture capital financing.
Walk Score offers an advertiser-supported version and a Premium Walk Score Neighborhood map version. To have the premium Walk Score map on your website the fee is “tier” based, calculated on how much it is used. For example, to have 5000 daily Walk Score map views the charge is $150.00 a month.
According to Walk Score’s website, Walk Score is on over 20,000 realtor, apartment rental and other residential “for sale” type websites. (You can check out Walk Score on Zillow, ForRent.com, MRED and others.)
Here are Walk Score’s definitions for its various values:
90–100 – Walker’s Paradise (Errands do not need a vehicle.)
70–89 – Very Walkable (Most errands can be done on foot.)
50–69 – Somewhat Walkable (Some errands can be done on foot.)
25–49 – Car-Dependent (Most errands need a vehicle.)
0–24 – Car-Dependent (Almost all errands need to be done by car.)
What Is Walk Score?
According to Wikipedia, “Walk Score is an algorithmically derived walkability index based on the distance to the closest amenity in each of several categories. . .”
Dr. Lucas J. Carr, working at the Department of Exercise and Sport Science at East Carolina University, led a research study titled, “Walk Score As a Global Estimate of Neighborhood Walkability,” published in the American Journal of Preventative Medicine.
Carr and his co-authors explain that walk score calculates a score of “walkability” from data provided by Google. Walk Score calculates its score based on the distance (from a given address) to 13 categories of amenities: hardware stores, clothing/music, grocery stores, coffee shops, restaurants, movie theaters, schools, parks, libraries, bookstores, fitness centers, drugstores, and bars. The categories are each given the same weight and points are totaled and normalized to give a Walk Score of 0-100.
What Does Walk Score Claim To Do?
By glancing at a couple of pages from Walk Score’s website, I found that Walk Score claims to help people “find a walkable place to live.” Their mission is to “promote walkable neighborhoods.” This is very noble goal. Who does not want to live in a walkable neighborhood?
The question is, what the heck does walkable mean? Well, it depends on who you ask.
Dictionary.com defines “walkable” as:
1. capable of being traveled, crossed, or covered by walking.
2. suited to or adapted for walking.
The earlier Wikipedia Walk Score definition and Dr. Carr’s definition of Walk Score do not reveal anything in the Walk Score calculation that helps determine whether an area is capable of being traveled by walking or “suited to or adapted” for walking.
Obviously, just because someone lives in proximity of several hardware stores (or other amenities) does not mean they can actually walk to them. We all know there are areas that lack sidewalks or are “cut off” from nearby amenities by busy multi-lane roads and other barriers.
The definition of walkable is not limited to Dictionary.com.
Another source to consider is The Online TDM Encyclopedia. TDM stands for Transportation Demand Management. The encyclopedia is a respected, comprehensive resource, created and maintained by the Victoria Policy Resource Institute. The institute is a research organization that strives to find innovative answers to transportation problems.
The TDM Encyclopedia defines a “walkable community” by quoting Dan Burden of Walkable Communities (www.walkable.org).
Burden is an amazing walking advocate and you can read his biography at Walkable and Livable Communities Institute. In brief, he was named one of the “Top 100 Urban Thinkers” by Planetizen, while Time Magazine said he is “one of the six most important civic innovators in the world.” He is also on the board of advisers for Walk Score.
Dan Burden’s definition:
A “walkable community” is designed for people, to human scale, emphasizing people over cars, promoting safe, secure, balanced, mixed, vibrant, successful, healthful, enjoyable and comfortable walking, bicycling and human association.
It is a community that returns rights to people, looks out especially for children, seniors and people with disabilities and takes aggressive action to reduce the negative impacts of sixty-plus years of auto-centric design and uncivil driving practices.
It is also a community that emphasizes economic recovery of central neighborhoods, promotes the concepts of recovering and transforming suburban sprawl into meaningful villages, and especially takes ownership and action to protect and preserving open space.
A walkable community, like a livable community, smart growth community, or sustainable community, makes a neighborhood, hamlet, village, town, city or metropolis into a place where many people walk, ride bicycles and use transit, and where anyone who drives a car moderates their behavior in a way where they take nothing from the rights of those who wish to stay healthy and active by taking part in activities outside the car.
A walkable community is one that is old, historic, well worn, restored sensibly and worthy of protection. A walkable community is one that is compact, new, fresh, invigorating and teaming with people enjoying their streets, parks, plazas, buildings and other physical space.
I know it’s long, but if you just skimmed over it–don’t! It is well worth reading, and striving for. Burden’s definition is extremely thorough and reasonable, however, it does not directly mention what Walk Score calculates — “distance to amenities.” So is Walk Score even figuring out something that the experts consider part of a walkable community?
Well, I think they are, but to a very small extent.
Indirectly, we can reasonably presume that part of a walkable community is having amenities within walking distance. Walk Score does SEEM to meet this indirect part of Burden’s definition.
Can One Aspect of “Walkable” Be Considered Independent Of Other Aspects?
The problem for Walk Score is some of the most walkable aspects may not be present in a high-scoring location. Worse, a lack of very “walkable” aspects could call into question a high Walk Score. In other words, places that are rated fairly walkable (like East Chicago, Indiana) could be unpleasant for a stroll, while others scoring lower (like Crown Point, Indiana) might be ideal for an afternoon amble.
In another study led by Dr. Carr, “Validation of Walk Score for Estimating Access to Walkable Amenities” (British Journal of Sports Medicine), the scientists discuss the fact that for some areas, “poor neighborhood aesthetics and high crime” may outweigh pro-walkable characteristics and make the area less walkable.
In this vein, Dr. Carr’s research mentioned earlier (Am J Preventive Medicine) found:
“positive associations between Walk Score and reported crime.”
This finding is particularly disturbing in light of the fact that someone looking to buy a home in a walkable community may inadvertently find themselves walking in what Walk Score calls a “Walker’s Paradise,” but may have put themselves at risk for assault, rape, theft, murder and so on.
Dr. Carr and his co-authors say Walk Score’s association with crime reveals a limitation of Walk Score and they “warrant caution” in its use. They state:
“. . . although Walk Score may serve as an estimate of access to facilities, it also positively correlated with reported crime in 2 successive years. . .”
In a separate study led by Dr. Stephanie B. Jilcott-Pitts of the Department of Public Health at East Carolina University titled, “Associations Between Neighborhood Amenity Density and Health Indicators Among Rural and Urban Youth” published in the American Journal of Health Prevention, these researchers also concluded:
“Walk Score was positively correlated with crime.”
Given that two respected research groups, independently, and through differently designed studies in different geographic regions both proved a statistically significant and positive association between Walk Score and crime, we must conclude that these results are likely true.
Related research led by Dr. S. McCrady-Spitzer at the Mayo Clinic, looked at Walk Score as it relates to poverty. Some scientists believe poverty and crime are related. Whether this is the case is not entirely clear. Regardless, most people agree that areas with high poverty are likely to be rundown, and though they may have a many amenities (likely fast food establishments, convenience stores, check cashing outlets and so on), most people would not choose to walk in such areas.
McCrady-Spitzer and her team published the paper, “Walk Score and Poverty in American Cities” in the Journal of Science and Medicine in Sport. This comprehensive study analyzed data from 520 U.S. cities with a population over 30,000 people, examining data from 103,405,474 people (one third of the population).
The scientists found:
“Unexpectedly, the cities with greater poverty and lower income, have the most favorable Walk Score.”
In other words, areas with high poverty are rated high by Walk Score.
Some people may believe that a higher population density in itself equates to more crime. However, the Jiltcott-Pitts’ research (above) took into account rural areas and still found an association between crime and Walk Score. Dr. McCrady-Spitzer and her fellow authors also considered population in itself in their paper and concluded: “There is no relationship between city population and Walk Score.”
Lastly, the possible association between population density and crime was questioned by other researchers and shown to be incorrect. A study done by Dr. Jianling Li (University of Texas) and Jack Rainwater (Senior Planner, City of Irving, Texas), titled “The Real Picture of Land Use Density and Crime: A GIS Application” and presented at the 2000 Esri conference, found a “high crime rate is not necessarily linked to high-density development.“ These scientists determined that crime was associated with socioeconomic status.
Returning to Dr. Carr and his team, they issue this caution:
“It is therefore recommended that Walk Score be used as a proxy for estimating neighborhood density and access to amenities rather than a global measure of neighborhood walkability.”
Walk Score’s creators admit its shortcomings. On How It Does Not Work page of their website, they clearly explain that Walk Score does not take into account:
1. Street design, including road speeds, safety of crossings, and sidewalk availability
2. Crime, car crashes and street lighting
3. Community design
4. Topography, such as hills that can make walking difficult
I am glad they disclaim crime, but I am not sure this is an adequate warning when someone is on Zillow reading through dozens of listings and likely considering each home or apartment’s Walk Score.
The creators of Walk Score describe it as an “approximation.” Even this description of Walk Score may be inaccurate. Can one approximate “walkable” by looking at the factor of “distance to amenities” by itself, in isolation of other “walkable” factors?
As a physician, I was trained to look at the whole person. If I were only to check a patient’s blood pressure and it is normal, can I say they are “approximately healthy”? Clearly, diabetes, thyroid problems, high cholesterol or a host of other aspects of the definition of “healthy” could – at times – overshadow a great, well-controlled blood pressure.
Alex Steffen, a noted author who has been featured on various media outlets (NPR, the Today Show and so on), has written an insightful article on Walk Score, titled, “The Problem With Walk Score.” In the article, Steffen comments on Walk Score’s list of walkability factors that it’s creators readily admit it does not consider, saying, “. . . these factors are not incidental. They’re fundamental.“
Going back to Walk Score’s “Somewhat Walkable” definition of East Chicago, Indiana, we find an area with crime that is nearly double the U.S. average, low scenic beauty, pollution from extensive nearby industry and so on. Do these other factors invalidate Walk Score’s rating of how “walkable” the area is?
The fact is Walk Score is only analyzing a very small sliver of whether a given address is “walkable.” In some cases, Walk Score’s “distance to amenities” and “density of amenities” will correctly equate to how to “walkable” an address is, but this seems to be more a matter of luck than science.
Or maybe not? Perhaps, something else is going on.
Another Look at the Walk Score Methods
A study that was led by Dr. Dustin T. Duncan from the Harvard School of Public Health, titled, “Validation of Walk Score for Estimating Neighborhood Walkability: An Analysis of Four U.S. Metropolitan Areas.” This study analyzed Walk Score for four metropolitan areas for four different geographic areas in the United States. The scientists found that Walk Score was “valid in measuring certain aspects of walkability” for each of four metropolitan areas in the study.
At first glance, this is encouraging. However, the four metropolitan areas were comprised of urban and suburban areas, not rural. The scientists’ state:
“Future Walk Score research is especially needed using geospatial datasets that vary in degree of urbanicity (including rural areas). . .”
Since Duncan and his group of scientists only looked at metropolitan areas, it is apropos to mention Dr. Carr and his team’s thoughts on this aspect of Walk Score.
In Dr. Carr’s study (in Br J Sports Medicine) he eludes to the fact that in this study (in Rhode Island), walkable amenities cluster in densely populated areas. It seems that high Walk Scores may be more a factor of density and clustering. Dr. Carr and his co-authors write:
“Importantly, addresses with higher Walk Scores were also more likely to be found in urban areas with a higher clustering of walkable amenities, while areas with lower Walk Scores were more likely to be found in rural areas with fewer numbers of walkable amenities.”
And more to the point –
“. . . Walk Score simply provides an estimate of the number and density of walkable amenities and should not be confused as measure of neighborhood walkability.”
After looking at the research on Walk Score, I believe Walk Score is computing distance and density of amenities very well. However, by equating this result to “walkable,” the average person looking for a walkable community may be misled. At best, Walk Score is a small aspect of what a “walkable community” means to most people.
Keep in mind that most people are not urban planners, scientists, and walking advocates; they are ordinary people. The term “Walk Score” and the mission of promoting “walkable neighborhoods” could easily mislead the man on the street into believing that a community with a high walk score may be a good place to walk. This may or may not be the case.
The term Walk Score could lead other people to believe that if they live in a high Walk Score area, they will walk more, lose weight and become more fit. With regard to fitness, research that has analyzed Walk Score’s relationship with exercise and weight loss has yielded some surprising results.
Does Living in a Highly Rated Walk Score Community Make You More Fit?
Walk Score does not make any DIRECT claims about the health and fitness advantages of living in a high Walk Score location. However, on their website, under the heading “The Science of Good Living,” they say that those of us who live “in walkable neighborhoods” weigh less, and that “Walkable places” make us healthier and happier.
These are general statements about “walkable communities,” and I would suspect they are correct (and nice to hear), but do they have anything to do with Walk Score?
Since the Walk Score creators state these facts on their website alongside other important Walk Score information, they create an implication that there is in fact a relationship between Walk Score and weight, health and happiness.
A Tighter Focus on Walk Score
The first research I reviewed along these lines was conducted by a team of scientists led by Dr. Paul Y. Takahashi of the prestigious Mayo Clinic. Takahashi and his team of scientists published their findings in the journal of Risk Management and Healthcare Policy. The paper was titled, “A Cross-Sectional Survey of the Relationship Between Walking, Biking, and the Built Environment for Adults Aged Over 70 Years.”
Takahashi and his team analyzed the association between Walk Scores and activity levels (walking and bicycling) in people of the ages 70 to 85 years old in Rochester, Minnesota. The study was relatively small (53 participants), but the results were surprising. The authors state:
“. . . there was no difference in Walk Scores between those older adults who walked or biked, compared to those who did not.”
The authors discuss why there was no positive association between walking or biking with Walk Score, and (as other researchers mention in their research) they explain that Walk Score does not consider the “quality or accessibility of sidewalks, bike lanes, or traffic.” The scientists also write that Walk Score does not take into account the “quality of the infrastructure.”
Takahashi and his co-authors conclude, “Using local knowledge and data may bear out relationships not revealed through use of the Walk Score.”
When one sees Walk Score next to a home listing on a real estate website (or elsewhere) there is a supposition that Walk Score has taken into account some of that “local knowledge and data,” which it does—but in a very narrow and very limited capacity.
More Questions about Walk Score
Research led by Dr. Dana L. Riley from the University of Ottawa Heart Institute, Canada, investigated the association between individuals’ physical activity and the built environment. The study was titled, “Neighbourhood Walkability and Physical Activity Among Family Members of People with Heart Disease Who Participated in a Randomized Controlled Trial of a Behavioral Risk Reduction Intervention,” and published in 2013 in the journal Health & Place.
Participants in the intervention arm of the study had significantly higher chances of meeting physical activity guidelines (compared to the control group) at 12 weeks. A total of 292 people took part in the study with Walk Scores that ranged from zero to 98. Surprisingly, the scientists found:
“There was no significant difference [in physical activity] based on Walk Score. . .”
The researchers discuss the high discordance rate of Walk Score (39.4%) and recommend: “Additional research that compares Walk Score to other objective measures of walkability is warranted.”
Clearly, these studies imply that Walk Score has no bearing on how much people walk. But can living in a highly rated Walk Score community make you healthier?
Returning to previous study by Dr. Jilcott-Pitts (in the Am J Health Promotion), she and her team examined associations between the built/social environment (amenities, crime) and health indicators (time spent doing moderate to vigorous physical activity, cardiovascular fitness and body mass index) among rural and urban youth. The study had nearly 300 participants.
As background, body mass index or BMI in simplified terms represents an indicator of body fatness (generally) based on a person’s height and weight. The higher a person’s BMI, the fatter the person is. A BMI of 30 or more means the person is considered obese.
These scientists discovered that body mass index (BMI) was positively and statistically associated with Walk Score. In other words, the higher the Walk Score the fatter the participants.
The scientists also found that Walk Score was inversely associated with time spent doing moderate to vigorous physical activity. That is, the better the Walk Score the less time people in the study spent doing moderate to vigorous physical activity.
Lastly, the study found Walk Score was positively associated with “lower fitness.” As an aside, if a higher Walk Score means people have more fat, it stands to reason that these people are doing less physical activity and are also less fit.
Given that most people looking to live in a walkable community are doing so to experience more physical activity, avoid obesity (or excess weight), and have a good (or great) level of fitness, the findings of this study are disappointing.
Recalling that this study by Jilcott-Pitts and her team found a positive association between Walk Score and crime, the scientists state:
“These counterintuitive findings may be due to the negative effect of crime. . . which may outweigh potential positive health impacts of high neighborhood amenity density.”
In discussing this paper with Dr. Jilcott-Pitts (via email), she said:
“. . . we concluded that crime was the bigger issue (potentially). In high Walk Score neighborhoods, sometimes crime is a problem. That prevents people from being physically active.”
Before we rule out Walk Score’s relationship with health benefits, we need to look at another study led by Jilcott-Pitts. This time the results at first glance appear more encouraging.
Good News for Walk Score, But Are They Walking?
More research for Walk Score’s association with health comes from a different study led by Dr. Jilcott-Pitts, titled, “Associations between Body Mass Index, Shopping Behaviors, Amenity Density and Characteristics of the Neighborhood Food Environment Among Female Adult Supplemental Nutrition Assistance Program (SNAP) Participants in Eastern North Carolina” and published in the journal Ecology of Food and Nutrition (2012).
In this study, Jilcott-Pitts and her team analyzed associations between body mass index (BMI) and the food environment among women participating in the Supplemental Nutrition Assistance Program (SNAP) in eastern North Carolina.
The scientists found that BMI was inversely associated with Walk Score. So the higher the Walk Score, the lower the woman’s BMI. They speculate that the healthy weight relationship with Walk Score may relate to participants in the study “having access to a combination of neighborhood amenities and/or food venues.” Oddly, whether the participants actually walked or not was not taken into account.
It is not clear what Walk Score represents in the scope of this study. Clearly, it has less (or nothing) to do with walking and more about “amenity access,” “density” or “variety.” This information may prove useful for science and society, and it is certainly worth looking into in more detail. But it makes me question what Walk Score’s value is regarding your health. Certainly, the inferences of health on Walk Score’s website (as they relate to Walk Score) are questionable.
Dr. Carr (in Am J Preventative Medicine) sums up Walk Score’s relationship on health, stating:
“To our knowledge, Walk Score has not yet been shown to predict physical activity behavior. . .”
In the research paper published by Dr. Duncan and his co-authors (above), the authors refer to Walk Score as relevant for “utilitarian walking as opposed to walking for exercise.”
Clearly, those people who want to walk to enjoy the great outdoors cannot rely on Walk Score. Walk Score is useful for those people who do not own a vehicle or who desire to walk to amenities (even if in some cases they need to carry a can of mace or even a 9mm).
Joking aside, I love Walk Score. Even if it does not help people who want to walk for health find a beautiful place to walk, it gets people thinking about walking. That matters. Walking is overlooked, undervalued and at the heart of what makes humans unique in the world.
Given the positive association between poverty and crime with Walk Score, there is the potential for realtor’ websites to make a home or apartment in such a location appear “better” or more walkable. With Walk Score in use on over 20,000 residential realtor sites, it’s a safe guess that some home buyers are being inadvertently misled.
The likelihood exists for someone to buy a home or rent an apartment based in part on Walk Score only to find themselves and their family living in a high crime, poverty-stricken neighborhood or simply in an area that is not conducive to walking.
I hope you recognize the things that concern me about Walk Score. I also hope you are concerned, too. Maybe together, we can encourage these “civic” minded folks at Front Seat to make their claims about Walk Score clearer, or – even better – bring Walk Score’s algorithm into line with their claims.
Regardless, what Front Seat chooses to do, realtor sites that use Walk Score may want to educate their visitors about Walk Score’s potentials risks and also explain it’s actual, very slim, limited benefit with regard to finding a “walkable” home.
At a minimum…
The walkability of an area cannot be accurately determined (or even approximated) by looking solely at one factor of walkability (in Walk Score’s case “distance to amenities”) without considering other significant factors (such as crime, weather, area attractiveness and so on).
If you know of anyone who is using a realtor website to find their dream home or apartment or if you know a realtor who displays Walk Score, please show them this research. They will thank you. I will too.
Lastly, Walk Score’s website advises, “You should use the Web 3.0 app called going outside and investigating the world for yourself.” It also recommends using Google Street View, if we are unable physically to go to a neighborhood. As I read these recommendations, I had to wonder, if I need to do all that, what is the point of Walk Score?
Note: I graciously thank Dr. Jilcott-Pitts for discussing her fascinating research with me and Dan Burden for allowing me the use of his definition of “walkable community.” Learn about Dan at www.walklive.org. Zillow, ForRent.com, MRED, and Walk Score are Registered Trademarks. As a disclaimer, I did not read all of Walk Score’s website. I only read parts of some pages on their website. With regard to Walk Score research, I relied on research that was published in recognized, peer-reviewed journals. Further, there may be other reputable, peer-reviewed studies about Walk Score that I overlooked. If you know of other research, please send it over – I would love to read more!
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