Gregory 2008b.

Study characteristics
Methods	12 months trial with 2 arms Dynamic deconstructive psychotherapy (DDP) Treatment‐as‐usual (TAU) Duration of trial: 12 months Country: USA Setting: outpatient
Participants	Methods of recruitment of participants: clinical setting Sample size: 30 Diagnosis of borderline personality disorder: Diagnostic and Statistical Manual of Mental Disorders, 4th Edition (DSM‐IV) Means of assessment: Structured Clinical Interview for DSM‐IV Axis II Disorders (SCID‐II) Mean age: 28.7 years (standard deviation = 7.7) Sex: 80% female Comorbidity: comorbid diagnosis of active alcohol abuse or dependence (not in full sustained remission) required for inclusion Incluson criteria 18 to 45 years Diagnosis of borderline personality disorder Active alcohol dependence or abuse Exclusion criteria Schizophrenia Schizoaffective disorder Mental retardation Neurological condition that may produce secondary psychiatric symptoms (e.g. stroke, multiple sclerosis, partial complex seizures, or traumatic brain injury)
Interventions	Experimental group Treatment name: DDP Number randomised to group: 15 Duration: 12 months (post‐treatment), weekly individual Control/comparison group Comparison name: TAU Number randomised to group: 15 Duration: 12 months (post‐treatment) Both groups Concomitant psychotherapy: If not already in treatment, TAU patients were referred to an alcohol rehabilitation centre and given names of clinics and therapists in the community. If they had one, TAU participants were allowed to keep their current psychotherapist. DDP participants were required to end treatment with their present psychotherapist, unless that person served primarily as a case manager or substance use counsellor. 70.0% of participants received individual psychotherapy or alcohol counselling, 30.0% received an additional professional group therapy, 36.7% participated in self‐help groups. Concomitant pharmacotherapy: 63.3% of all participants received separate medication management. The mean number of psychotropic medications was 2.9. Medication management was provided by the DDP therapist for patients in the DDP group according to the American Psychiatric Association guidelines for borderline personality disorder. Medications specifically targeting substance use disorders were not prescribed. [The] “average number of psychotropic medications used during first 12 months of treatment: control group, mean number N = 2.67, SD 1.45; DDP mean number N = 2.34, SD = 1.61" (Gregory 2010, p. 293). 75% of both groups were taking psychotropic medications during the follow‐up period; average number of psychotropic medications used: control group mean number = 1.88 (SD = 1.55), DDP group mean number = 1.63 (SD = 1.30) (Gregory 2010, p. 294). Number of psychotropic medications at end of treatment: DDP 2.0 (SD 1.56), TAU 2.89 (SD 1.69) (Gregory 2008, Tab. 2, p. 33). Proportions of participants taking standing psychotropic medication during trial observation period: n (%) receiving separate medication management: DDP 0%, TAU 56% (Gregory 2008, Tab. 2, p. 33)
Outcomes	Primary BPD severity, assessed with the Borderline Evaluation of Severity Over Time (BEST) Self‐harming behaviour, assessed by the number of patients with parasuicide in the previous 3‐month period Secondary Dissociation/stress‐related paranoia, assessed with the Dissociative Experiences Scale (DES) Depression, assessed with the depression subscale of the The Depression, Anxiety and Stress Scale (DASS)
Notes	Sample size calculation: not stated Ethics approval: not stated Comments from review authors: none
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote: "A minimization method was employed for group assignment [...] ensuring comparability of the two groups on key variables or factors [...] The specific factors that we adjusted for included: age, gender, alcohol abuse versus dependence, current alcohol use, antisocial personality disorder, inpatient utilization, and number of parasuicides." ( p. 31‐32)
Allocation concealment (selection bias)	Low risk	Quote: "participants were assigned by the research coordinator to either the investigation treatment or to treatment‐as‐usual (TAU) in the community". (p. 31)
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Quote:"An independent, trained research assistant administered the primary and secondary outcome measures [...] blind to treatment group at the time of interviews, but blindedness was only partial, as she was able to correctly guess group assignment 67% of the time (50% correct guesses were expected by chance alone)." (p. 35)
Incomplete outcome data (attrition bias) All outcomes	High risk	Comment: the authors conducted per protocol analyses (EG: 10/15 allocated; CG: 9/15 allocated).
Selective reporting (reporting bias)	Low risk	Comment: a study protocol is available (NCT00145678) and there were no indications of selective reporting
Other bias	High risk	Performance bias: "Six therapists provided DDP, including the principal investigator [who is one of the two developers of DDP] (PI; N = 6 study participants) and five psychiatry residents (N = 9 participants) who were in their third year of residency training [...] After achieving competency, adherence to technique and treatment integrity for resident therapists was assured through weekly group supervision [...] and individual supervision of videotaped sessions with the PI [principal investigator, developer of DDP] every other week throughout treatment." (Gregory 2008b, p. 34) Allegiance bias: Both developers of the experimental treatment were among the study authors. Attention bias: Though participants of the control group did not receive an alternate, obligatory control treatment, but were free to join alternative treatments, they did not receive less professional attention. "[...] DDP participants received fewer overall treatment contact hours than did participants receiving community care." (p. 39). Also cf. Tab. 2, p. 33.