Objective: Online support groups for individuals with substance use disorders are regularly used, yet little is known about participant engagement patterns. Preliminary research has examined utilization and perceived benefits of an abstinence-focused online social network. This study sought to extend these findings by examining participant characteristics, engagement, and perceived benefits of online support groups for individuals with broader personal substance use goals (Harm reduction, Abstinence, and Moderation Support [HAMS]). Method: HAMS members were invited to complete an online survey about their HAMS engagement (N = 343). The average age of participants was 41.55 (SD = 12.61) and most identified as White (93.9%), female (78.8%), and cisgender women (70.1%). Participants completed measures of HAMS participation, substance use goal, quantity/frequency of substance use, mental health history, negative substance use-related consequences, and quality of life. Results: Most participants (67.1%) reported a substance use moderation goal and alcohol was the most commonly used substance (91.6%). Participants most frequently reported visiting HAMS on Facebook (89.5%), visiting HAMS daily (39.2%), and visits typically lasted up to 30 min (86.1%). Most participants somewhat or strongly agreed HAMS helped them feel better about changing their use of drugs/alcohol (87.1%; M = 4.41/5; SD = 0.81), increased their motivation for changing their use of drugs/alcohol (89.2%; M = 4.44/5; SD = 0.77), and increased their selfefficacy in reaching/maintaining the substance use goals (85.1%; M = 4.29/5; SD = 1.05). Conclusions: Online support for broader personal substance use goals may be beneficial for individuals who seek to stop/ limit their substance use. Online support is well suited for obtaining quick, inexpensive access to support. Public Health Significance StatementThis cross-sectional study indicates an online support group for individuals with harm reduction, abstinence, and moderation substance use goals helps individuals feel better about changing their use, increases their motivation for changing their use, and increases their self-efficacy to achieve/maintain their substance use goals based on self-report. This study offers support for nonabstinence goals being preferable for some individuals who are seeking to change their substance use. Online support groups for individuals seeking support for their substance use might be particularly beneficial for individuals with limited access to treatment services or who need quick/inexpensive access to support.

Objective: Online support groups and social network sites for individuals with substance use disorders are regularly used yet little is known about how individuals engage with them. This study sought to extend research on online support groups/social network sites by examining engagement with an online Harm reduction, Abstinence, and Moderation Support (HAMS) group.Method: HAMS members were invited to complete a brief online survey about their HAMS engagement (n=343). The average age of participants was 41.55 (SD=12.61) and most identified as White (93.9%), female (78.8%), and cisgender women (70.1%). Participants completed measures of HAMS participation, substance use goal, quantity/frequency of substance use, mental health history, negative substance use-related consequences, and quality of life.Results: A majority of participants (67.1%) reported a substance use moderation goal and alcohol was the most commonly reported substance used (91.6%). Participants most frequently reported visiting HAMS daily (39.2%) and visits typically lasted up to 30 minutes (86.1%). The most common engagement methods were reading a Facebook group post (89.5%) and posting in the Facebook group (72.9%). Most participants somewhat or strongly agreed HAMS helped them feel better about changing their use of drugs/alcohol (87.1%, M=4.41/5, SD=0.81), increased their motivation for changing their use of drugs/alcohol (89.2%, M=4.44/5, SD=0.77), and increased their self-efficacy in reaching/maintaining the substance use goals (85.1%, M=4.29/5, SD=1.05).Conclusions: Online support for harm reduction, abstinence, and moderation goals may be beneficial for individuals who seek to stop/limit their substance use. Online support is well-suited for individuals seeking quick, inexpensive access to support.