Schema Therapy for Chronic Depression

To compare the efficacy of schema therapy versus active monitoring for women with chronic depression receiving psychiatric care.

A randomized, assessor-blind, single center, superiority trial will be conducted. Participants will be referred to clinical psychologists in a private counseling office (Senzoku Stress Coping Support Office, in Japan). Eligible participants will be women with chronic depression receiving psychiatric care. Participants will receive schema therapy or active monitoring during 2 years. Primary outcome will be treatment response. A total sample size of 64 (32 in each group) would be required to provide 80% power at a 2-sided significance level of 5% to detect a risk difference of 35% (response rate: 55% for schema therapy vs. 20% for active monitoring), assuming a dropout rate of 10%.

Participants will be randomly allocated into two groups using a web-based central allocation system. This system will confirm allocation concealment and random sequence generation.

Schema therapy in an individual format will be implemented by clinical psychologists. The treatment period will be 2 years with biweekly 50-minute sessions (up to 48 sessions).

Active monitoring by telephone will be implemented by clinical psychologists. The treatment period will be 2 years with monthly 10-minute sessions (up to 24 sessions).

Schema therapy for chronic depression, a face-to-face psychological intervention by clinical psychologists.

Treatment response was defined as 50% or greater reduction in depressive symptoms (the 17-item GRID-Hamilton Depression Rating Scale; GRID-HAMD) at 104 weeks compared with baseline. The GRID-HAMD will be administered by clinical psychologists who will be blinded to treatment assignments.

Change in observer-rated depression severity was defined as the change score of the 17-item GRID-HAMD from baseline through 104 weeks.

Change in observer-rated depression severity was defined as the change score of the 24-item GRID-HAMD from baseline through 104 weeks. The 24-item GRID-HAMD will be administered by clinical psychologists who will be blinded to treatment assignments.

Change in self-rated depression severity was defined as the change score of the Beck Depression Scale-II (BDI-II) from baseline through 104 weeks.

The cumulative medical costs during 104 weeks for the utilization of medical services will be assessed at each session.

Inclusion Criteria: Persistent depressive disorder including chronic major depressive disorder and dysthymic disorder assessed by the Structured Clinical Interview for DSM Scores of at least 14 on the GRID-HAMD Psychiatric treatment duration for depression of at least 3 years Exclusion Criteria: Psychiatric hospitalization within 30 days prior to the enrollment Ineligible to receive the protocol treatment during 2 years Schizophrenia Bipolar disorders Intellectual disabilities Neurocognitive disorders Substance-related disorders

IPD will be available to other researchers within 3 years after the publication of the primary paper.