Article Text

other Versions

Download PDFPDF
Using synthetic control methodology to estimate effects of a Cure Violence intervention in Baltimore, Maryland
  1. Shani A Buggs1,
  2. Daniel W Webster2,
  3. Cassandra K Crifasi2
  1. 1Violence Prevention Research Program, Department of Emergency Medicine, University of California Davis, Sacramento, California, USA
  2. 2Center for Gun Violence Prevention and Policy, Johns Hopkins University Bloomberg School of Public Health, Baltimore, Maryland, USA
  1. Correspondence to Dr Shani A Buggs, Violence Prevention Research Program, Department of Emergency Medicine, University of California Davis, Sacramento, CA 95817, USA; sabuggs{at}


Objective To estimate the long-term impact of Safe Streets Baltimore, which is based on the Cure Violence outreach and violence interruption model, on firearm violence.

Methods We used synthetic control methods to estimate programme effects on homicides and incidents of non-fatal penetrating firearm injury (non-fatal shootings) in neighbourhoods that had Safe Streets’ sites and model-generated counterfactuals. Synthetic control analyses were conducted for each firearm violence outcome in each of the seven areas where Safe Streets was implemented. The study also investigated variation in programme impact over time by generating effect estimates of varying durations for the longest-running programme sites.

Results Synthetic control models reduced prediction error relative to regression analyses. Estimates of Safe Streets’ effects on firearm violence varied across intervention sites: some positive, some negative and no effect. Beneficial programme effects on firearm violence reported in prior research were found to have attenuated over time.

Conclusions For highly targeted interventions, synthetic control methods may provide more valid estimates of programme impact than panel regression with data from all city neighbourhoods. This research offers new understanding about the effectiveness of the Cure Violence intervention over extended periods of time in seven neighbourhoods. Combined with existing Cure Violence evaluation literature, it also raises questions about contextual and implementation factors that might influence programme outcomes.

  • firearm
  • public health
  • safe community
  • case-control study
  • programme evaluation

Statistics from

Request Permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.


  • Contributors SAB and DWW were responsible for the conception and design of the project, as well as interpretation of data. SAB and CKC developed the coding for analysis. SAB was responsible for data collection and management, data analysis and drafting of the article. CKC and DWW contributed to critical revisions of the article. SAB, DWW and CKC provided final approval of the version to be published.

  • Funding This research was supported by the National Institute on Drug Abuse (5T32DA007292-23 and 4T32DA007292-24), the Centers for Disease Control and Prevention (1U01CE001954-01A1), and the Johns Hopkins Center for Gun Violence Prevention and Policy. Funders had no role in the study design, statistical analyses, interpretations of data or drafting of this article.

  • Competing interests None declared.

  • Patient consent for publication Not required.

  • Ethics approval This study was deemed to be 'not human subjects research' by the Johns Hopkins Bloomberg School of Public Health Institutional Review Board.

  • Provenance and peer review Not commissioned; externally peer reviewed.

  • Data availability statement Census block group-level data are available in a public, open access repository. Data on homicides, non-fatal shootings and arrests were obtained through both the Baltimore City Open Data portal ( and the Baltimore Police Department. Police Department data requests must be submitted to the agency.

  • Supplemental material This content has been supplied by the author(s). It has not been vetted by BMJ Publishing Group Limited (BMJ) and may not have been peer-reviewed. Any opinions or recommendations discussed are solely those of the author(s) and are not endorsed by BMJ. BMJ disclaims all liability and responsibility arising from any reliance placed on the content. Where the content includes any translated material, BMJ does not warrant the accuracy and reliability of the translations (including but not limited to local regulations, clinical guidelines, terminology, drug names and drug dosages), and is not responsible for any error and/or omissions arising from translation and adaptation or otherwise.