Carter 2010.

Study characteristics
Methods	Parallel‐arm, randomised controlled trial with 2 treatment arms Dialectical behavioral therapy (DBT) Treatment as usual + waiting list (TAU + WL) Duration of trial: 6 months (all participants were offered 12 months of DBT, but the comparison between groups was restricted to the first 6 months of DBT vs TAU + WL). Country: Australia Setting: outpatient
Participants	Methods of recruitment of participants: Participants were referred from treating general practitioners, treating psychiatrists or public mental health services (any units of Hunter Mental Health Services). Sample size: 73 Diagnosis of borderline personality disorder: Diagnostic and Statistical Manual of Mental Disorders, 4th edition (DSM‐IV) Means of assessment: clinical interview, ICD‐10 International Personality Disorder Examination (IPDE) Mean age: 42.5 years (standard deviation = 6.1) Sex: 100% female Comorbidity: participants showed substantial psychopathology with high rates of BPD criteria, International Personality Disorder Examination (IPDE) scores and Axis 1 comorbidity. Inclusion criteria: not stated Exclusion criteria Schizophrenia Bipolar affective disorder Psychotic depression Florid antisocial behaviour Developmental disability Disabling organic condition; "The psychiatrist assessor had the option of determining if any potential subjects were unsuitable for inclusion in therapy or unmotivated to participate, although there were no specific criteria for this exclusion." (quote, p 164)
Interventions	Experimental group Treatment name: DBT Number randomised to group: 38 Duration: 6 months (weekly individual therapy, weekly group‐based skills training, telephone access to an individual therapist, therapist supervision) Control/comparison group Comparison name: TAU + waiting list Number randomised to group: 35 Duration: 6 months (participants were offered DBT treatment after a 6‐month waiting period) Both groups Concomitant psychotherapy: participants were asked to discontinue psychological therapy of any sort for at least the 12‐month duration of dialectical behavior therapy (DBT) Concomitant pharmacotherapy: not specified Proportions of participants taking standing psychotropic medication during trial observation period: unclear
Outcomes	Primary Self‐harm, assessed as the number of patients with self‐harming behaviour Mental health status, assessed with Brief Disability Questionnaire ‐ subscale, days out of role Secondary Interpersonal problems, assessed with the World Health Organization Quality of Life Instruments (WHOQOL‐BREF) ‐ social relationships subscale
Notes	Sample size calculation: yes Ethics approval: not stated Comments from review authors: We received information about the trial from the first author via email.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Comment: the authors used a computerised random number generator to generate allocations ‐ placed into sealed opaque envelopes (in blocks of 8). Envelope drawn after baseline assessments complete". (Carter 2010 [pers comm])
Allocation concealment (selection bias)	Low risk	Quote: "Randomization was carried out by the research staff. [...] participants were allocated by selecton of sealed opaque envelopes." (p. 164)
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Quote: "Outcomes were determined [...] by assessors blinded to allocation. [...] All reasonable attempts were made to maintain blindness to allocation status for these raters, but this could not achieve perfect blindness." (pp. 164)
Incomplete outcome data (attrition bias) All outcomes	High risk	Comment: the authors conducted per protocol analyses (DBT group: 20 completers of treatment and self‐reports out of 38 allocated to this group; TAU group: 31 completers of waiting list and self‐reports out of 35 allocated)
Selective reporting (reporting bias)	Unclear risk	Comment: there was no indication for selective reporting, but Insufficient information to permit judgement of 'high' or 'low'.
Other bias	High risk	Performance bias: "The intervention condition was based on the comprehensive DBT model, a team‐based approach including [...] therapist supervision groups." (p. 163). "[...] possible inferiority of training of DBT therapists to that of those in other studies or inferior adherence to the DBT methods despite adequate training" (p. 170). There was no mention of any objective means of assessment. Allegiance bias: no indication of allegiance bias Attention bias: more attention paid to DBT group participants