Navigating non-positivity in neighbourhood studies: an analysis of collective efficacy and violence
Jennifer Ahern, Magdalena Cerdá, Sheri A Lippman, Kenneth J Tardiff, David Vlahov, Sandro Galea
J Epidemiol Community Health Feb 2013, 67 (2) 159-165; DOI: 10.1136/jech-2012-201317
