Search Results Use the search box below to revise your search, or start a new search. Studies (2) Variables Publications Your query returned 2 studies. Series results are grouped under the most relevant study. Ungroup series results to view all results. Sort by: Title A-Z Released/Updated Time Period Most Cited in ICPSR Bib. 1. Process and Outcome Evaluation of the Gang Resistance Education and Training (G.R.E.A.T.) Program, 2006-2011 [UNITED STATES] (ICPSR 34899) Esbensen, Finn-Aage; Osgood, Wayne; Peterson, Dana; et al. 2. School Culture, Climate, and Violence: Safety in Middle Schools of the Philadelphia Public School System, 1990-1994 (ICPSR 2026) Welsh, Wayne N.; Jenkins, Patricia H.; Greene, Jack R.