The effectiveness of Mentalization-Based Treatment-early (MBT-early) in adolescents with emerging borderline-personality disorder: a single case experimental design

Borderline personality disorder (BPD) is characterized by problems in emotion
regulation, identity disturbances, and impaired interpersonal functioning.
Because BPD may determine health and quality of life in long term, it is
important to focus on early detection and early intervention to prevent
worsening. In this study, the effectiveness of a new intervention, MBT-early,
is investigated in adolescents with borderline personality problems through a
single case experimental design (SCED).

Existing studies into the efficacy of psychotherapeutic interventions for young
people with a (subclinical) borderline personality disorder (BPD) show mixed
results. An obvious explanation therefore lies in the heterogeneity of the
samples studied, where the same intervention is investigated by young people
with some characteristics of borderline personality problems in an early stage
as by young people with significant borderline personality problems at a later
stage. However, there is evidence that interventions should be targeted
specifically at the stage of progression of the disorder ('staged care').
Interventions may be more effective when they correspond to the stage of
disease progression.
MBT-early is an intervention intended for young people in an early stage of
BPD. The intervention not only addresses the characteristics of BPD, it is more
generally aimed at improving personality functioning so that there is no
developmental stagnation and chronic consequences can be avoided.
The expected working mechanisms of MBT-early's are twofold. MBT-early tries to
strengthen the young person's mentalizing capacity. Mentalizing ability appears
to play a role in the development of borderline personality disorder and
improving mentalizing is a working mechanism of behind a MBT treatment.
However, more recent theories have identified another working mechanism of MBT
treatment, which is to increase epistemic trust (the openness to learn from
others).

Research questions:
1. What is the effectiveness of MBT-early in youth with early stage BPD?
o What effect does MBT-early have on the improvement of personality functioning?
o What effect does early MBT have on the degree of depressed mood?
2. What are the possible working mechanisms of MBT-early?
o Does the youth's mentalizing ability influence the improvement of personality
functioning?
o Does epistemic trust affect the improvement of personality functioning?
o What are the patients', parents* and therapists* perspectives on treatment
trajectories as illustrated by the quantitative data?
o What are the experiences of patients, parents and therapists regarding
helping and hindering factors over the course of the MBT-early treatment?

To study the effectiveness and exploratively the presumed working mechanisms of
the new MBT-early intervention. Given that MBT-early specifically targets young
people with early characteristics of borderline personality disorder, we expect
to find improvements in level of personality functioning and reductions of
depressieve symptoms (which is often the reason for seeking treatment).

Single Case Experimental Design (SCED).
Characteristic of a SCED design is that the 'state' of a participant is
monitored at different times by means of frequent repeated measurements, so
that the course of change as a result of the intervention can bemonitored. An
ABC design is used with three phases (A, B and C). Phase A is a baseline period
prior to treatment in which there is no active intervention, in which 6 weekly
assessments will be conducted. Phase B is the intensive intervention phase in
which weekly treatment sessions take place over a period of 16 weeks.
Assessment takes place as an integrated part at the beginning of treatment
sessions. Phase C entails the booster phase, in which 4 low-frequency treatment
sessions take place, spread over a duration of 6 months. In phase C assessment
will also take place at the outset of the booster therapy sessions (4
assessments).

Semi-structured interviews are performed with patients, parents and therapists
about their their experiences with MBT-early. Interviews focus on the
perspectives of patients, parents and therapist on the course of the treatment
(based on the collected SCED data). The interviews have a maximum duration of
60 minutes. Topics include reflecting on moments in the treatment trajectory
where improvement was observed in the questionnaires, interpreting these
improvements, and exploring potential explanations for stagnation.
Additionally, broader treatment experiences will be examined, including
satisfaction, factors that facilitated or hindered progress, and insights
gained by the patients.

MBT-early is an early intervention program for BPD that has been developed as
an adaptation of MBT, an empirically supported treatment for BPD. MBTearly
builds upon the theory and methods of MBT but integrates the principles of
early intervention approaches such as Helping
Young People Early (HYPE). MBT-early is a time-limited intervention that has
been designed for early-stage BPD and focuses on
improving personality functioning. MBT-early is a two-phase treatment that
integrates interventions at the individual, family, and context level.

Participation is entirely voluntary. Informed consent takes place after the
screening of the regular intake procedure. After giving information and
receiving the information letter, the young person has one week to consider
participation. The young person (and parents if the young person is not yet 16
years old) gives permission to participate. The difference from the standard
procedure of MBT-early is the addition of a baseline period of 6 weeks with 6
repeated measures (taken by telephone) and a slight adjustment of the original
ROM (23 instead of 16 items). The additional time investment for completing 23
versus 16 items is negligible. The standard waiting time is about 3-6 weeks, so
the baseline period required for the additional measurements are minimized.
The structural baseline period of 6 weeks is a (slight) deviation from the
regular route and may result in a limited delay (0-3 weeks) in starting regular
treatment. This six-week baseline period is necessary for a valid SCED design
with sufficient measurements in the first phase. We minimize the expected delay
to a minimal level because the preparation for the treatment process (attuning
with youth professionals, planning appointments, signing an arrangement), which
normally also takes a number of weeks, does start already. After these six
weeks the face-to-face treatment can start immediately. The questions of the
additionally included items do not differ in terms of content from the regular
lists and there are no additional critical items with regard to the regular
package. We therefore do not expect any increased risks or additional burden
from this.

The interviews will involve a maximum time commitment of 60 minutes. No
increased risks or additional burden are expected as a result of the questions
posed during the interviews.