Table 2. Summary of Studies Conducted on the Use of Family Intervention in Adolescent BPD.

BPD = borderline personality disorder; ATraPA = actions for the treatment of adolescent personality; ATraPA-TAI = actions for the treatment of adolescent personality, intensive outpatient treatment; ATraPA-FAL = actions for the treatment of adolescent personality, families on the border; DBT = dialectical behavioral therapy; DBT-A = dialectical behavior therapy for adolescents; EUC = enhanced usual care; RCT = randomized controlled trial; MBT-A = mentalization-based treatment for adolescents; TAU = treatment as usual; NNT = number needed to treat; CI-BPD = childhood interview for DSM-4-TR borderline personality disorder; SIPA = Stress Index for Parents of Adolescents

Authors	Intervention format	Design & Setting	Participant information	Outcome measures	Outcome
Whalen et al. (2014) [9]	Adolescents' Axis I and II symptoms were evaluated using semistructured clinical interviews. Adolescents and their mothers engaged in a structured conflict discussion task	Cohort study/outpatient	110 adolescent females aged 16 years and their biological mothers	International Personality Disorders Examination, The Revised Interactional Dimensions Coding System	Positive maternal and dyadic affective behaviors were associated with more rapid rates of BPD severity scores declining over time
Mayoral et al. (2020) [30]	ATraPA-TAI: group-based intervention containing skills group, individual therapy, and email therapy. ATraPA-FAL: 12-session psychoeducational group for parents. Alternatives Group: weekly 1-hour session with inpatient adolescents with self-injurious behavior running in the healthcare system for 7 years	Observational study/outpatient	Adolescents aged 13-17 presenting with emotional dysregulation and their families referred within the region of Madrid, Spain	Not applicable	Decrease in the number of self-injurious behaviors, increase in emotion regulation skills, better parent-child communication
Boritz et al. (2021) [31]	Caregivers of adolescent BPD patients underwent 12 weekly 90-minute sessions in a skills training group. Individual therapy for the patients was not conducted	Quantitative analysis/outpatient	94 caregivers of adolescent BPD patients	Primary outcomes: Burden Assessment Scale, Stress Index for Parents of Adolescents. Secondary outcomes: The Child Behaviour Checklist, The Family Experience Interview Schedule, The Pearlin Mastery Scale, The DBT-Ways of Coping Checklist, The Grief Scale	Primary outcomes (Caregiver Burden and Parenting Stress), as well as secondary outcomes (child behavioral concerns, affect, mastery, and coping), improved. All outcome measures, except the SIPA (Parent Domain), showed statistically significant improvements over time
Sheikhan et al. (2021)  [32]	Caregivers took part in semi-structured interviews at the end of 12 weekly 90-minute sessions in the form of a skills training group. Individual therapy for patients not conducted	Quantitative analysis/outpatient	13 caregivers of adolescent BPD patients	Interviews were audio-recorded, transcribed verbatim, de-identified and entered into qualitative analysis software for analysis	Three major themes regarding caregiver’s experience were identified: (a) caregiver's ability to manage their youth's mental health challenges was increased; (b) caregiver's inter-and intra-personal spheres were enhanced; (c) caregivers' experience led to proposed improvements to the program
Rathus et al. (2015) [25]	A demographic form (Treatment Acceptability Scale) and open-ended assessment administered following completion of the four or five-week module	Qualitative analysis/outpatient	50 participants recruited from three DBT programs in New York	Treatment Acceptability Scale scale, Child and Adolescent Mental Health Satisfaction Scale, DBT Skills Rating Scale for Adolescents	Middle path was regarded as helpful, interesting, and relevant. Overall both parents and adolescents rated it as most helpful. Both adolescents and parents considered conflicts reduced and relationships “closer” and “warmer”
Mehlum et al. (2014) [26], (2016) [27],  (2019) [28]	19-week DBT-A: Weekly individual therapy, multifamily skills training, family therapy sessions, and telephone coaching EUC: Standard care enhanced by 1 weekly treatment session/psychodynamic/cognitive behavioral therapy combined with psychopharmacological treatment as needed	RCT with 1-year and 3-year follow-up/outpatient	N = 77, DBT = 39, EUC=38, aged 12-18, 1-year follow-up: N = 75, DBT = 38, EUC = 37, 3-year follow-up: N = 71 DBT = 37, EUC = 34	Suicidal ideation questionnaire, Moods and feelings questionnaire, Beck hopelessness scale, borderline symptom list, number of self-reported self-harm episodes, Montgomery—Asberg depression rating scale—baseline and 19 weeks, hospital admissions and emergency department visits, child behavior checklist, children’s global assessment scale, lifetime parasuicide count interview,  suicide intent scale	DBT-A outperformed EUC in reducing suicidal and self-injurious behavior, suicidal ideation, and depressive symptoms. No significant group differences in borderline symptoms and hopelessness post-DBT.  First follow-up (2016): Significant between-group differences in self-harm for the DBT group, but not in suicidal ideation, global functioning, hopelessness, borderline and depressive symptoms. Additional follow-up (2019): Significant group difference in frequency of self-harm episodes for the DBT-A group. Both groups remained on average at the same levels for suicidal ideation, depressive symptoms, hopelessness, borderline symptoms, and general functioning as at the first follow-up (2016). In patients who received DBT-A, receiving more than 3 months of follow-up care in the first year following completion was linked to better outcomes
Rossouw et al. (2012) [29]	1-year MBT-A: Weekly individual MBT-A sessions and monthly MBT-F sessions TAU: routine care by community-based adolescent mental health services	RCT with measurement at 3, 6, 9, and 12 months postrandomization/outpatient	N = 80, MBT = 40, TAU = 40, F/M = 68/12, aged 12-17 years old	Primary outcome: Risk-Taking and Self-Harm Inventory. Secondary outcomes: Mood and Feelings Questionnaire, Risk-taking scale, Borderline Personality Features Scale for Children, How I Feel questionnaire, Experience of Close Relationships Inventory	Primary outcome: Both groups demonstrated significant reductions in self-harm and risk-taking behavior. Self-harm scores were significantly lower for the MBT-A group at the 12-month point. Secondary outcome: Using the cutoff point of 8 at the Mood and Feelings Questionnaire for probable clinical depression, a significantly fewer percentage of participants of the MBT-A group scored in the clinical range than the TAU group at 9 months and at treatment end respectively (41% versus 70%, p = 0.03, NNT = 3.5, 95% CI 2.07 to 21.12) and (49% versus 68%, p = 0.08, NNT = –5.31, 95% CI –2.45 to 30.62)