Social Science & Medicine 279 (2021) 114026 Available online 11 May 2021 0277-9536/© 2021 Elsevier Ltd. All rights reserved. Review article Peer support as a protective factor against suicide in trans populations: A scoping review Hannah Kia a, * , Kinnon Ross MacKinnon b , Alex Abramovich c, d , Sarah Bonato d a School of Social Work, The University of British Columbia, Vancouver, Canada b School of Social Work, York University, Toronto, Canada c Dalla Lana School of Public Health, University of Toronto, Toronto, Canada d Institute for Mental Health Policy Research, Centre for Addiction and Mental Health, Toronto, Canada A R T I C L E INFO Keywords: Transgender Minority stress model Scoping review Peer support Suicide Suicidal ideation Suicidal behavior ABSTRACT Rationale: There is a growing body of research involving transgender (trans) individuals that foregrounds elevated rates of suicidality in trans populations. Although peer support is increasingly studied as a protective factor against suicide among trans persons, the scholarship in this area continues to be limited and has yet to be synthesized and appraised. Objective: In this paper, we address this existing gap in the literature by presenting the results of a scoping review of the literature examining the signifcance and function of peer support in mitigating suicide risk in trans populations. Methods: This scoping review is based on an analysis of 34 studies that were included following the execution of a methodical search and selection process. Drawing on scoping review methodology, along with PRISMA-P guidelines, we selected peer-reviewed empirical works, published between 2000 and 2020, which examined relationships between providing, seeking, and/or receiving peer support and suicide risk in trans populations. Results: Our fndings, which are conceptualized using the minority stress model as a guiding theoretical framework, reveal that while the literature generally substantiates the protective signifcance of peer support for trans persons, a small body of work also uncovers novel and unanticipated sources of peer support, including social support offered by trans peers online, which are infrequently and inconsistently examined in this body of scholarship. Conclusions: Using our appraisal of the literature, we outline the need for future research to further elucidate the signifcance and function of peer support in protecting against suicide among trans persons. In particular, we discuss the need for exploratory inquiry to inform a conceptualization and operationalization of peer support that more fully and consistently accounts for how such support (including online and community-based support) is sought, received, and experienced among trans persons in the context of suicide. 1. Introduction Transgender (trans) individuals often report exceptionally high rates of suicidal ideation and behavior, relative to their cisgender (non-trans) counterparts (James et al., 2016; Wolford-Clevenger et al., 2018). For example, in a recent survey of 27,715 trans people from across the United States, 40% of respondents indicated having attempted suicide at least once in their lifetime, which refects a suicide attempt rate nearly nine times higher than that of the general United States population (James et al., 2016). Rates of suicidal ideation and behavior may be even higher among trans persons who report co-occurring mental health and substance use issues (Valentine and Shipherd, 2018), along with those who are racial minorities (James et al., 2016), those living in poverty (Wolford-Clevenger et al., 2018), and those living with disabilities (James et al., 2016; Wolford-Clevenger et al., 2018). Several studies in the area of trans health have drawn attention to the likely role of exposure to minority stress factors, including violence, stigmatization, and discrimination targeting trans identity, in height- ening suicide risk among trans persons (James et al., 2016; Su et al., 2016). Others have also highlighted the possible salience of social * Corresponding author. School of Social Work The University of British Columbia, Hannah Kia, School of Social Work, 2080, West Mall, Vancouver, BC, V6T 1Z2, Canada. E-mail address: hannah.kia@ubc.ca (H. Kia). Contents lists available at ScienceDirect Social Science & Medicine journal homepage: www.elsevier.com/locate/socscimed https://doi.org/10.1016/j.socscimed.2021.114026 Received in revised form 19 April 2021; Accepted 7 May 2021