Among young people with borderline personality disorder (BPD), findings demonstrated that effective early intervention did not depend on availability of specialist psychotherapy but did need youth-oriented clinical case management and psychiatric care.

• This single-blinded randomized clinical trial was conducted to assess the effectiveness of 3 early interventions for BPD of differing complexity.

• The included interventions were: (1) The Helping Young People Early (HYPE) dedicated BPD service model for young people, integrated with weekly cognitive analytic therapy (CAT); (2) HYPE plus a weekly befriending psychotherapy control condition; and (3) a general youth mental health service (YMHS) model, plus befriending; thus, the 3 treatment arms were HYPE + CAT, HYPE + befriending, and YMHS + befriending.

• Main outcome was psychosocial functioning, evaluated with the Inventory of Interpersonal Problems Circumplex Version and the Social Adjustment Scale Self-report.

• A mean of 19.3% to 23.8% improvement in the primary outcomes and 40.7% to 52.7% for all secondary outcomes, except severity of substance use and client satisfaction, was evident from baseline to 12 months irrespective of the group.

• According to planned comparisons (YMHS + befriending vs HYPE; HYPE + CAT vs befriending), the service model or the psychotherapy intervention was not linked with a superior rate of change in psychosocial functioning by the 12-month primary endpoint.

• Regarding treatment attendance and treatment completion, the HYPE service model was found to be better than YMHS + befriending.

• Superiority of HYPE + CAT over befriending was found with regard to treatment attendance (median [IQR], 12 [16.5] vs 3 [9.8] sessions) and treatment completion (24 of 46 [52.2%] vs 29 of 93 [31.2%]).