Individuals with minoritized sexual and gender identities (i.e., LGBTQ+ individuals) are at a greater risk for self-injurious thoughts and behaviors than their cisgender, straight peers (Haas et al., 2010; Liu et al., 2017; Gorse, 2022). There is a dearth of empirically supported interventions for self-injurious thoughts and behaviors (Linehan, 2008; Riblet et al., 2017), and those that exist are not tailored to people in the LGBTQ+ community (Gorse, 2022; Haas et al., 2010). Therefore, the aim of this study is to test the effectiveness of a brief LGBTQ+ affirming text message intervention in reducing self-injurious thoughts and behaviors among LGBTQ+ individuals.

Scope of the work

LGBTQ+ individuals are at a greater risk for self-injurious thoughts and behaviors than their cisgender, straight peers. Despite this known risk, there are no culturally sensitive empirically supported treatments for self-injurious thoughts and behaviors for LBGTQ+ individuals. Therefore, the aim of this study is to test the effectiveness of a brief LGBTQ+ affirming text message intervention in reducing self-injurious thoughts and behaviors among LGBTQ+ individuals. Participants will be 100 LGBTQ+ adults who report self-injurious thoughts and/or behaviors in the last month. All participants will do 14 days of ecological momentary assessment (brief assessments on their mobile device 5 times a day) pre-randomization. After this period, half the participants will receive 2 brief affirming messages a day (morning and afternoon) for 14 days, and half of the participants will receive no messages for 14 days. The text messages will be designed to communicate belonging and importance for LGBTQ+ individuals in society (e.g., "There are over 9,000,000 LGBTQ+ people in the United States. You are not alone". Then all participants will complete another 14 days of ecological momentary assessment. During the assessment periods, participants will report on experiences of discrimination, belongingness, perceived burdensome, and self-injurious thoughts. We predict that participants in the mobile health condition will have a significant decrease in self-injurious thoughts and behaviors from pre- to post-intervention, whereas there will be no change in the control condition. We also predict that participants in the mobile health condition will lead to a significant decrease in thwarted belongingness and perceived burdensomeness. Finally, we predict that our intervention will help break the link between of experiences discrimination and self-injurious thoughts and behaviors by reducing feelings of thwarted belongingness and perceived burdensomeness in response to sexual and gender minority stress. If the effectiveness of our intervention is supported by the data, this intervention could be scaled up and be made available to the LGBTQ+ community broadly.

Inclusion Criteria:

• be 18 years or older b) have an LGBTQ+ identity (e.g., a sexual orientation other than exclusively straight and/or a gender identity other than exclusively cisgender) c) report at least one self-injurious thought (e.g., suicidal or nonsuicidal self-injury ideation), or behavior (nonsuicidal self-injury, suicide attempt) in the last month

Exclusion Criteria:

• Younger than 18, exclusivilty cisgender, heterosexual, no history of SITB in the last month