Stephen S. Leff, PhD
Areas of expertise: Aggression and bullying prevention programming, Community-based participatory research models for intervention and measurement development, Racial and intersectional microaggressions, ADHD and peer relations, Gender and social cognitive differences in aggression
About Stephen S. Leff
Stephen S. Leff, PhD, is the Co-Director of the Center for Violence Prevention at CHOP, a licensed Psychologist, and the William H. Bennett Professor of Psychology in Pediatrics at the Perelman School of Medicine at the University of Pennsylvania. His research focuses on aggression and bullying prevention programming, relational aggression which is the use of rumors and social exclusion to harm others, racial and intersectional microaggressions, the community-based participatory research process which is working with community stakeholders to integrate their voices and perspectives into best practice empirically-supported programming, and Scientific Edutainment which integrates empirical science with the latest entertainment technology in order to make educational programming evidence-based, engaging and relevant to youth. Dr. Leff has been the recipient of six prior NIH grants, as well as a range of other federal, local, and foundation awards to support his intervention research. He is strongly committed to issues of diversity, equity, inclusion, and anti-racism.
Titles
Co-Director of the Center for Violence Prevention at Children's Hospital of Philadelphia
Professor of Clinical Psychology in Pediatrics and Psychiatry, Perelman School of Medicine at the University of Pennsylvania
Research Interests
Aggression and bullying prevention
Community-based partnership methods for developing interventions
Racial and Intersectional Microaggressions
ADHD and peer relationships
School-based prevention
Education & training
Undergraduate Degree
BA - Duke University, Durham, NC
Graduate Degree
PhD - University of North Carolina, Chapel Hill, NC
Internship
Philadelphia Child Guidance Center, Philadelphia, PA
Fellowship
Children's Seashore House of The Children's Hospital of Philadelphia, Philadelphia, PA
Publications
Publications
2018
Mehari, K.R., Moore, W., Waasdorp, T.E., Varney, O., Berg, K., & Leff, S.S.: Cyberbullying Prevention: Insight and Recommendations from Youth, Parents, and Pediatricians. Child: Care, Health & Development. Page: 1-7, 2018 Notes: DOI:10.1111/cch.12569.
2017
Leff, S.S. & Feudtner, C. : Tackling Bullying: Grounds for Encouragement and Sustained Focus. Pediatrics 139(6), June 2017 Notes: doi:https://doi.org/10.1542/peds.2017-0504.
2016
Leff, S.S., Waasdorp, T.E., & Paskewich, B.: The broader impact of Friend to Friend (F2F): Effects on teacher-student relationships, prosocial behaviors, and relationally and physically aggressive behaviors. Behavior Modification 40(4): 589-610, 2016.
2015
Leff, S.S., Paskewich, B.S., Waasdorp, T.E., Waanders, C., Bevans, K.B., & Jawad, A.F.: Friend to Friend: A randomized trial for urban African American Relationally Aggressive Girls. Psychology of Violence 5(4): 433-443, 2015 Notes: Published online: doi:http://dx.doi.org/10.1037/a0039724.
2011
Leff SS, Lefler EK, Khera GS, Paskewich B, Jawad AF: Preliminary examination of a cartoon-based hostile attribution bias measure for urban African American boys. American Journal of Community Psychology 49: 332-346, 2011.
Leff SS, Thomas DE, Shapiro ES, Wilson K, Paskewich B, Necowitz-Hoffman B, Jawad AF: Developing and validating a new classroom climate observation assessment tool. Journal of School Violence 10: 165-184, 2011. PMCID: PMC3106103.
Editorials, Reviews, Chapters
2023
Forthcoming
Leff SS, Fu R, Varghese J. Strategies for Addressing Racial and Intersectional Microaggressions and Macroaggressions. Anger, Aggression, and Violence: Causes, Pathology and Treatments. In Martin, C., Patel, V.B. & Preedy, V.R. Springer Nature, in press.
Leff SS, Waanders C, Iyengar SS. Disruptive Behavior Disorders, Aggression, and Oppositional Defiant Disorder. Developmental-Behavioral Pediatrics. Forthcoming.
2018
Leff, S.S., Waasdorp, T.E, & Mehari, K. R.: An Updated Review of Existing Relational Aggression Programs. In S. M. Coyne, & J. M. Ostrov (Eds.), The development of relational aggression; (pp. 283-317, Chapter xiii, 348 Pages) Oxford University Press, New York, NY. 2018 Notes: https://proxy.library.upenn.edu/login?url=https://proxy.library.upenn.edu:2072/docview/2153379440?accountid=14707
Leff, S.S., Streit, K.V., & Paskewich, B.S.: Supporting Urban Youth through Play: Facilitating Social and Emotional Skills. Promoting Prosocial Behaviors in Children through Games and Play: Making Social Emotional Learning Fun. Laura Nabors & Renee Hawkins (eds.). Nova Science, Page: 147-175, 2018.
Bradshaw, C. P., O'Brennan, L.M., Waasdorp, T.E., Pas, E., Blumenstyk, J., Bartolo, D., & Leff, S. S.: The New Frontier: Leveraging Innovative Technologies to Prevent Bullying. Cambridge Handbook of Violence Behavior and Aggression (2nd Ed.). A. Vazsonyi, D. Flannery, & M. Delisi (eds.). Page: 724-735, 2018 Notes: 2nd edition.
2017
Waasdorp, T.E., Horowitz-Johnson, Z., & Leff, S.S.: Cyberbullying across the lifespan: Risk factors and consequences. Handbook of Bullying Prevention: A Lifecourse Perspective. C.P. Bradshaw (eds.). National Association of Social Workers (NASW) Press, Page: 69-80, 2017.
2014
Leff SS, Waasdorp TE, Waanders C, Paskewich BS. Better understanding and intervening to prevent relational aggression. In: Weist MD, Lever NA, Bradshaw CP, Owens JS, editors. Handbook of School Mental Health: Research, Training, Practice, and Policy, 2nd ed. New York: Springer; 2014. p. 171-84.