Dr. Eugenia C. Garvin, a resident in the Department of Emergency Medicine at the Perelman School of Medicine at the University of Pennsylvania, said the study used a randomized controlled trial design. Researchers randomly selected two clusters of vacant lots -- one which was later greened, and one that was not.
Twenty-one residents living near both sites were interviewed before and after the greening. Survey results show that residents living near the greened vacant lots felt significantly safer at the three-month follow-up visit compared with those near the control site, Garvin said.
The research team also analyzed police reported crime data from three months before and three months after the greening and found total crime, as well as assaults with and without a gun, was less after the greening, the study said.
"Vacant lot greening changes the physical environment of a neighborhood from one that may promote crime and fear to one that may reduce crime and make people feel safer," Garvin said in a statement.
"Our theory is that transforming vacant lots from a space overgrown with vegetation and filled with trash to a clean and green space may make it difficult for people to hide illegal guns and conduct other illegal activities such as drug use in or near the space."
The findings were published online in Injury Prevention.