The study design for this proposal is a stratified, randomized, single-blind, non- inferiority trial comparing the current standard of care for treatment of Hoarding Disorder (HD), Group Cognitive Behavioral Therapy (G-CBT), to an innovative and promising community-based treatment, Group Buried in Treasures (G-BiT). Participants will be stratified by gender, psychiatric status (high vs. low burden of psychiatric symptoms) and insurance status (insured vs. under- or un-insured) so that equal numbers of individuals with each of these characteristics are randomized to each treatment arm. They will then be randomly assigned (randomized) to either G-CBT or G-BiT. Participants will know which treatment group they are assigned to, but those members of the research team who are conducting clinical or neuropsychological assessments or analyzing the data will not; they will be blinded to participant group assignment, and group leaders will be blinded to the psychiatric status, neurocognitive status, insurance status, etc, of participants. The study is a non-inferiority trial, that is, the hypothesis to be tested is that G-BiT is as effective, or no less effective, than G-CBT. We chose a non-inferiority design because we have no reason to believe G-BiT is better than G-CBT and our preliminary data, as well as outcomes previously reported for G- CBT and G-BiT, suggest that these treatments may have similar efficacies.
