Therapists and treatment fidelity
Therapists were licensed psychotherapists with at least 3 years of psychotherapy experience. Therapists were trained in either DIT or GST before they could begin to treat study participants. Training in DIT and GST were conducted separately by experts in these approaches. DIT therapists attended a 5-day workshop that included 3 days of theoretical courses and 2 days of practical exercises. GST therapists attended a 3-day workshop that provided an overview of GST, a review of the GST treatment manual, and practical exercises. After training, only therapists who showed competency in either DIT or GST served as study therapists. Of these, 14 DIT therapists saw an average of 4.7 patients and 18 GST therapists saw an average of 4.2 patients. The study therapist attended a 3-h meeting every 3 months to review therapy-related knowledge. The therapists in each treatment group were equivalent with respect to number of years of psychotherapy experience (Each therapist provided only one type of treatment and received 90-min group supervision every 2 weeks. Experienced therapists conducted the supervision to ensure the accuracy and consistency of treatment implementation. All of the DIT and GST sessions were audiotaped. For each patient, three sessions representing the beginning, middle, and end phase of therapy were reviewed by independent senior psychotherapists to establish treatment adherence and fidelity. We used the DIT session rating form in the clinician guide of DIT to assess the adherence (Lemma et al., 