PHILADELPHIA — Street lighting, illuminated walk/don’t walk signs, painted crosswalks, public transportation, community parks, and maintained vacant lots are associated with significant decreased likelihood of homicide among youth in a city neighborhood, according to a study published today in JAMA Pediatrics from researchers at the Perelman School of Medicine at the University of Pennsylvania and Children’s Hospital of Philadelphia (CHOP). The findings offer implications for future randomized intervention trials to reduce youth violence by revitalizing neighborhoods.
Homicide was the cause of 2043 deaths of adolescents in the United States in 2014, yet limited research exists on environmental changes that can make neighborhoods safer.
“Modern medical advances have reduced fatalities resulting from assaults cases, but medical teams and communities face the grim realities of what clinical medicine can achieve in saving critically injured patients,” said Charles C. Branas, PhD, a professor of Epidemiology, director of the Penn Injury Science Center and senior author on the study. “We must do what we can to prevent these homicides from occurring on the front end – and this research is part of that puzzle. By identifying attributes of communities and their association with homicides, these findings offer insights for targeted interventions to prevent violence.”
The team compared Philadelphia Medical Examiner’s Office data of 143 homicide victims ages 13 to 20 from 2010 to 2012 in Philadelphia with that of 155 matched control individuals of the same age range and outdoors in the city when the homicides occurred. They compared features of the immediate surroundings in locations where homicides occurred to the locations where control individuals were at the same time.
Field staff photographed the street corner closest to where the homicides occurred and the control locations and converted the images into 360-degree high resolution panoramas. Trained coders identified 60 visible elements of the built and social environments, such as broken sidewalks or trash, to develop a picture of environmental characteristics associated with the violence. The information was also supplemented by additional insights and details of each homicide from the Philadelphia Police Department.
“This research is exciting because it provides an initial glimpse into specific modifiable neighborhood features that may put youth at risk of severe violent injury. While we can’t determine from this study if any of these features cause violence, it provides important insight into things we may want to target in future intervention trials,” according to the study’s lead author, Alison Culyba, MD, MPH, an adolescent medicine physician in the Craig-Dalsimer Division of Adolescent Medicine at CHOP and PhD candidate in Epidemiology at Perelman School of Medicine. “Our research adds to a growing body of knowledge suggesting that modifying environmental risks for violence may provide opportunities for practical and sustainable interventions that can save lives.”
Previous Penn research suggested that greening vacant lots – cleaning and removing debris, planting grass and trees, and installing a low wooden post-and-rail fence – had many benefits including finding that residents who walked near newly greened vacant lots felt safer and had significantly lower heart rates than those near blighted lots, and that remediating abandoned, inner city buildings was associated with a 39 percent reduction in certain gun crimes. Additional Penn research recently mapped paths of urban males to assess how to minimize their violence risk. These findings led researchers to research associations between specific neighborhood characteristics and homicides.
The researchers note that homicides stem from complex individual, relational and environmental factors, and that further research is needed to understand how environment changes may lead to a change in homicide rates.
Co-authors include Joel A. Fein, MD from CHOP and the Perelman School of Medicine, Sara F. Jacoby, PhD, MPH, from Perelman School of Medicine; Therese S. Richmond, PhD, CRNP, from the Penn School of Nursing; and Bernadette C. Hohl, PhD, MPH, from Rutgers University.
For more information, see CHOP release.
This work was supported by National Institutes of Health grants R01AA016187, R01AA014944, and T32HD043021, and Centers for Disease Control and Prevention grant R49CE002474.
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