Trichotillomania (TTM) is characterized by hair pulling that is repetitive in nature leading to notable hair loss, causing clinically significant distress and resulting in impairments across social and functional domains (APA, 2013). Trichotillomania causes significant social impairment including affecting close relationships, pursuing occupational changes or advancement, or interfering with schooling (Grant et al., 2017; Woods, Flessner, Franklin, Wetterneck, et al., 2006). The core of the treatment of trichotillomania has traditionally been Habit Reversal Training (HRT) (Twohig, Bluett, et al., 2014). Another form of treatment that is gaining empirical support is Acceptance and Commitment Therapy (ACT) which has been studied in four randomized controlled trials, one studying ACT as a standalone treatment (Lee, Homan, et al., 2018), and three examining ACT combined with HRT (Twohig et al., 2021; Lee, Haeger, et al., 2018; Woods, Wetterneck, et al., 2006) which demonstrated efficacy of the combined treatment in decreasing pulling symptom severity.

The prevalence of trichotillomania in the US is 1-2% of the population and yet treatment access is limited by many issues including processionals' lack of knowledge of the disorder and low treatment accessibility (Walther et al., 2010). ACT- enhanced behavior therapy has been implemented using telehealth to reach a larger population (42.2% decrease pre-to-post treatment), but telehealth still requires therapist time and incurs notable costs (Lee, Haeger, et al., 2018). The present study aims to address the gap in trichotillomania treatment accessibility by examining the role of check-ins on adherence and efficacy on afully automated, web-based ACT-enhanced HRT treatment for adults with trichotillomania across the United States. We predict that the condition with check-ins will increase adherence and efficacy of the treatment significantly more than the condition without check-ins. Additionally, we predict that hair pulling severity and psychological flexibility will be significantly improved by the condition with check-ins compared to the condition without check-ins.

Inclusion Criteria:

1. Currently meet DSM-5 criteria for trichotillomania
2. searching for trichotillomania-based treatment
3. are atleast 18 years old
4. fluent English speakers
5. living in the U.S.

Exclusion Criteria:

1. currently receiving alternative therapy
2. currently modifying or starting psychotropic medication
3. previously met DSM-5 criteria for trichotillomania but are not, at the time of intake session, engaging in hair pulling