Indicator ST.3.e Number and rate of pedestrian injuries
* Annual rate calculated from 2004-2008 SWITRS data and 2007 population data from Applied Geographic Solutions, Inc. N/A = Excluded due to small population size.
** N=52 pedestrian injury records did not include intersection data that would allow them to be geocoded. Those injuries are therefore not represented in the neighborhood totals but are included in the overall total for San Francisco.
Data Source
Data on collisions resulting in pedestrian injuries and fatalities provided by the California Highway Patrol, Statewide Integrated Traffic Records System (SWITRS). More information can be found at: http://www.chp.ca.gov/switrs/.
SWITRS data was geocoded by Jeff Burton, San Francisco Department of Public Health. Pedestrian injuries are calculated from records from the SWITRS "Victim" table where Victim Role = 3 (Pedestrian) and Victim Degree of Injury = 1 (Killed), 2 (Severe Injury), 3 (Other Visible Injury), or 4 (Complaint of Pain). Population data for rate calculations is from the Applied Geographic Solutions, Inc. Spring 2007 Update: Current Year Estimates. Methodology available at: http://www.appliedgeographic.com/library.html.
Maps and tables prepared by City and County of San Francisco, Department of Public Health, Environmental Health Section using ArcGIS software. Map data is presented at the level of the census tract.
The map also includes planning neighborhood names, in the vicinity of their corresponding census tracts. Table data is presented by planning neighborhood. Planning neighborhoods are larger geographic areas then census tracts. SF DPH used ArcGIS software and a 'centroids within' methodology to convert census tracts to geographic mean center points. We then assigned census tracts to planning neighborhoods based on the spatial location of those geographic mean center points and calculated the planning neighborhood totals for the table.
Detailed information regarding census data, geographic units of analysis, their definitions, and their boundaries can be found in the HDMT at the following links:
http://www.thehdmt.org/etc/Geographic_Units_of_Analysis.pdf
http://www.thehdmt.org/data_map_methods.php
Explanation and Limitations
The California Highway Patrol defines "pedestrians" as any person not in or upon a vehicle, bicycle, or animal. This includes a person in or operating a pedestrian conveyance, such as a baby carriage, coaster wagon, skateboard, roller skates, skis, sled, non-motorized and motorized wheelchair, and a person in or upon a device moved by pedaling, except a bicycle. This excludes a person boarding or alighting from a conveyance, except a pedestrian conveyance, and a person jumping or falling from a motor vehicle.
According to the San Francisco Injury Center, San Francisco is a major tourist destination and employment hub for the Bay Area. The major corridors of the city have extremely high traffic volumes, and also tend to have high rates of pedestrian injuries and deaths.
Notably, many individuals who may be in San Francisco do not reside within city limits (i.e., commuting employees, students, visitors and tourists). The San Francisco Injury Center estimates that in addition to the 469,000 vehicles registered to San Francisco residents and businesses, there are an estimated 435,000 vehicles that come in and out of San Francisco daily. The Center also estimates that 32% of hospitalizations in San Francisco hospitals are not for San Francisco residents, but rather visitors and guests, or persons transferred in from another hospital to SF for specialized medical care. (Profile of Injury in San Francisco, The San Francisco Injury Center and San Francisco Department of Public Health, December, 2004. Accessed online on October 26, 2006: http://www.surgery.ucsf.edu/sfic/profile05.pdf)
SWITRS data includes injuries on a public roadway that are reported to the California Highway Patrol. However, many collision injuries go unreported. Given San Francisco's ethnic diversity, there may be certain neighborhoods which would be more or less likely to report injuries to authorities than others. For example, neighborhoods with higher immigrant densities may have lower reporting rates because of fear of deportation, whereas neighborhoods with a strong community police presence may be more likely to report collisions.
The Pedestrian Environmental Quality Index is a measure being developed by the San Francisco Department of Public Health, Environmental Health Section that attempts to account for these numerous factors. See Indicator ST.3.f for more information.
Pedestrian injuries have also been mapped to the nearest intersection by the San Francisco Department of Public Health, and are accessible at the following link: http://www.sfdph.org/dph/comupg/oprograms/CHPP/TrafficSafety/default.asp.
Why is this a Community Health Indicator?
Approximately 800 people walking on San Francisco streets are injured or killed by cars annually.a The population rate of injuries, approximately 100/100,000 resident population, is five times the national Health People 2010 Objective of no more than 19 injuries and 1 fatality per 100,000 population.b While 11% of traffic deaths nationally are to pedestrians, 50% of traffic deaths in San Francisco are people walking on the city's streets.a
Parental concerns about the lack of traffic lights and controlled crossings on their child’s school route reduce the likelihood that their child will actively commute to school.c In an evaluation of a Safe Routes to School program, the presence of pedestrian safety measures at street crossings was associated with a greater likelihood of walking to school for children.d
- CCSF MTA (City and County of San Francisco Municipal Transportation Agency Traffic Engineering Division), 2007. San Francisco 2006 Collision Report. San Francisco, CA. http://www.sfmta.com/cms/rtraffic/documents/Collision_report_2006.pdf, accessed on 8 April 2008.
- USDHHS (U.S. Department of Health and Human Services), 2000. Healthy People 2010: Understanding and Improving Health. 2nd ed., U.S. Government Printing Office, Washington, DC.
Davison KK, Lawson CT. Do attributes in the physical environment influence children's physical activity? A review of the literature. Int J Behav Nutr Phys Act. 2006;3:19.
Boarnet MG, Anderson CL, Day K, McMillan T, Alfonzo M. Evaluation of the California Safe Routes to School legislation: urban form changes and children's active transportation to school. American Journal of Preventive Medicine. 2005;28:134–140.