Making space: A randomized waitlist-controlled trial of an acceptance and commitment therapy website for hoarding

Background: Hoarding disorder causes significant impairment, but existing treatments have notable barriers to access and do not target several psychological processes that may contribute to hoarding. Therefore, this study evaluated an acceptance and commitment therapy (ACT) self-help website for hoarding with minimal coaching in a randomized waitlist-controlled trial to evaluate initial feasibility and efficacy. Methods: Participants were 73 U.S.-based adults with clinically significant hoarding symptoms. The website comprised 16 self-help sessions to be completed over 8 weeks. Measures were taken at baseline, posttreatment, and 1-month follow-up.Results: Multilevel models indicated that the ACT condition improved significantly more than waitlist on hoarding symptom severity (the primary outcome; beta = 0.74, Holm-corrected p = .01) as well as secondary outcomes (e.g., functional impairment, well-being, and progress toward personal values, Holm-corrected ps < .05). Rates of reliable (34.61%) and clinically significant (11.54%) change at posttreatment were limited, with no significant differences between groups. Responses indicated that this intervention was acceptable, credible, and easy to use, although adherence could be further improved.Conclusions: Overall, results suggest that an ACT self-help program for hoarding can be acceptable and efficacious. Limitations include a predominantly White and female sample and the lack of an active control condition.