Adherence Priming Clinical Trial
Official title:
Microtuning a Bonafide Treatment for GAD Patients - A Randomized Controlled Trial.
Background: Psychotherapy is an effective treatment for generalized anxiety disorder in
comparison to no-treatment controls. Instead of creating more and more new overall
treatment-packets within a medical meta-model, a complementary approach to investigate
clinical research designs may lie into the understanding of already effective
psychotherapies. Treatment manuals and protocols allow a relatively high degree of freedom
of therapists' behaviors on how to implement the overall treatment manuals. There is a lack
of systematical knowledge of how therapists have to customize these overall protocols. The
present design experimentally examines 3 types of conducting a 15 session time-limited
cognitive-behavioral therapy (CBT) protocol and its relation to the therapists' protocol
adherence and treatment efficacy.
Methods/design: This trial investigates 3 different types of how to customize a
well-introduced CBT-protocol using dyadic peer tutoring methodology (primings). The
individuals with GAD are randomly assigned to 3 priming conditions (resource priming vs.
supportive resource priming vs. adherence priming). Participants' treatment allocation is
performed randomly, therapist's assignment to the peer tutoring partner and the priming
condition is based on mutual agreement. Treatment outcomes are assessed at following levels:
Observer based in-session outcomes, post-session outcomes from session 1 to 15, treatment
outcome at post assessment and at 6-months follow-up assessments.
Aims of the trial. This trial investigates 3 different types of how to customize a
well-introduced CBT-protocol (Zinbarg, Craske, & Barlow, 2006) using dyadic peer tutoring
methodology (primings). The participants are randomly assigned to 3 priming conditions: (a)
Resource priming (Flückiger, Wüsten et al., 2010; Flückiger & Grosse Holtforth, 2008a); (b)
Supportive resource priming and (c) Adherence priming.
The main research questions are:
1. In-session outcomes. Using the videotapes, observer-based videoanalyses will be
conducted: (a) Do the resource priming conditions show comparable observer-based
therapist's adherence in comparison to the adherence priming condition (Zinbarg et al.,
2007)? (b) Do the resource priming conditions show more resource activating micro
interventions than the adherence priming condition (ROMA; Flückiger & Grosse Holtforth,
2008a/b)? (c) Are the in-session processes predictors and mediators of session and
therapy outcomes (Flückiger et al., 2009; Flückiger et al., 2013)?
2. Post-session outcomes. Are there differences in the post-session outcomes of the 3
priming conditions? Furthermore: Are the post-session outcomes along with symptom
change predictors and mediators of therapy outcome (Flückiger et al., 2009; Flückiger
et al., 2012)?
3. Treatment outcomes. Do show the resource priming conditions comparable efficacy on GAD
outcomes, general outcomes and dropout rates in comparison to the adherence priming
condition?
Methods/Design. This study is a randomized controlled trial with three active treatment
arms. This trial is conducted at the Swiss psychotherapy outpatient clinic from the
Department of Psychology at the University of Zürich. The treatments are based on the same
treatment protocol (Zinbarg et al., 2006). Overall, a 3 x 4 design with one between-subject
factor (resource priming vs. supportive resource priming vs. problem priming) and one
within-subject factor (time: pre, mid (session 6), post (session 14), 6-months follow-up).
Participants. Inclusion/Exclusion Criteria. Participants will be included in the study if
they: (a) are 18 years or older; (b) agree to the informed consent, (c) have sufficient
knowledge of German; and (d) fulfill the diagnostic criteria of GAD DSM-IV criteria.
Participants will be excluded if they have: (a) a score of 2 or higher on the suicide item
of the BDI and/or with active suicidal plans according to the diagnostic screening
interview, (b) a current medication of psychotic or bipolar disorder, (c) a current
treatment by a professional psychotherapist. Further, prescribed medications for anxiety or
depressive disorders do not lead to exclusion if the dosage has remained constant for at
least one month. The presence of a comorbidity does not result in exclusion if GAD is in the
foreground according to the severity rating of the Diagnostic Interview for DSM-diagnoses.
Recruitment. Participants will be recruited by means of advertisements in newspapers and
through internet forums. The high-circulation newspapers are delivered for free in the Swiss
public transport systems. Interested individuals in participation will contact the study
office via SMS, e-mail or phone. Screened positive patients are invited for an intake
assessment to verify the inclusion and exclusion criteria based on a standardized interview.
Participants that are not screened positive are informed about more appropriate treatments
via phone call or if requested by a further face-to-face contact.
Randomization and treatment allocation. After meeting the inclusion criteria, patients are
randomized to the 3 conditions (resource priming, supportive resource priming, adherence
priming). Treatment allocation is performed randomly by online application of a full
randomization. In this way, we aim to ensure that trial arms are balanced with respect to
the patients' baseline characteristics. Randomization procedure is conducted by two
independent research assistants. Because all patients are treated by the same CBT-manual,
patients are blinded for the treatment allocation and are not informed about the
randomization procedure.
GAD treatment protocol. CBT-manual (Zinbarg et al., 2006): Traditional cognitive-behavioral
therapy (CBT) for GAD typically consists of psycho education of generalized anxiety
disorder, relaxation training (RT), cognitive restructuring (CR) and with some in-vivo
situational exposure for patients with overt behavioral avoidance (e.g., Barlow, Rapee, &
Brown, 1992; Borkovec & Costello, 1993). Furthermore, imagery exposure as a GAD-specific
form of in-sensu exposition will be applied to reduce experiential avoidance based on a
well-introduced CBT-manual (Zinbarg et al., 2006). The manualized therapy follows an usual
time-limited treatment format of 14 sessions to 50 minutes and a booster session after
6-months (total 15 sessions).
Tandem peer tutoring (priming).
To investigate various types of how to conduct a standardized CBT-protocol, all therapists
are tutored in peer dyads (tandem peer tutoring). Immediate before sessions 1 to 5, the
therapists are required to contact the tandem-partner face-to-face or via self-phone to
deliberate the forthcoming session by a 5 to 10 minute brief communication (primings; for a
comparable procedure see Flückiger & Grosse Holtforth, 2008). The tandem peer tutoring are
grouped in three conditions:
1. Resource priming: Immediately before sessions 1 to 5, therapists have a five-minute
conversation about how to implement strengths-based micro-interventions in the
forthcoming session. Strengths-based micro-interventions addresses therapists explicit
focus on patients' preexisting strengths and abilities, subtle changes and improvements
during therapy (potential recources) as well as motivational preparedness, readiness
and goals (motivational resources; Grawe, 2006; Flückiger et al., 2010).
2. Supportive resource priming: The supportive resource priming condition has the very
same protocol as the resource priming condition (5 brief tandem peer tutorings). The
only difference in the procedure is that the therapists are allowed to integrate a
helpful significant person of the patients (such as the partners or the best friends)
around session 1 and 7 to encourage and support the patient to realize their treatment
plans (active integration of interpersonal resources). However, the integration of a
significant other person does not touch the CBT-treatment protocol.
3. Adherence priming: Immediately before sessions 1 to 5, therapists have a five-minute
conversation about how to implement the disorderspecific interventions that are
described in the treatment protocol. These communications are focused on therapists'
understanding of patients GAD and the related comorbidities and how these issues can be
addressed in the prescriptive treatment protocol.
Therapists. Twelve advanced trainees with at least 2 years post-graduate training are
recruited from local (CBT)-training centers. The majority of the therapists have experience
as study therapists in a prior randomized controlled trial. All the therapists participate
in an initial 16-hour workshop presented by the developer of the treatment manual (Zinbarg
et al., 2006). In addition to the peer-tutorings (primings), the therapists have regular
supervision in small groups on a 14-day basis. The supervision is conducted in mixed groups
over the 3 priming conditions. All the supervisors also participate in the initial 16-hour
workshop. To respect and coordinate the therapists' preferences (e.g. preferences in working
days and time schedules) they were assigned in a joint face-to-face session at study start.
All the therapists gave verbal and written consent to the selected peer-tutoring partner and
priming condition.
Assessments. At intake, GAD-diagnosis and its core symptomatology are identified according
to the structured interview section for GAD (DIPS; Margraf, Schneider, & Ehlers, 1994).
Furthermore, GAD-criteria are assessed by self-reports. The individual worries are
identified using the Penn State Worry Questionnaire (PSWQ) and the Worry Domain
Questionnaire (WDQ). Mental disorders on Axis I are assessed using face-to-face diagnostic
interviews for Axis I (Diagnostisches Interview für Psychische Störungen für DSM-IV, SCID-I)
and for Axis II (Strukturiertes Klinisches Interview für DSM-IV, Achse-II,
Persönlichkeitsstörungen, SKID-II; Wittchen, Zaudig, & Fydrich, 1997).
PSWQ, Beck Anxiety Inventory (BAI) and the State-Trait Anxiety (STAI) are used as
GAD-outcomes. Premature termination from the trial, the interpersonal problems and strengths
inventories, the behavioral inhibition and activation scale, as well as the resource
potential questionnaire are used as general outcomes. The outcome measures are taken at
intake, directly after session 6 (end of primings), session 14 (post-assessment), and at 6-
month follow-up.
The following process measures are examined: (a) Post-session reports (Flückiger et al.,
2010), working alliance (Munder et al., 2009) and symptom change (BAI) are conducted from
session 1 to 15 and (b) In-session processes: Using the recorded videotapes, adherence
ratings (Zinbarg et al., 2007), the Resource-Oriented Microprocess Analysis (ROMA-P/T,
Flückiger & Grosse Holtforth, 2008) and the level of explication scale (Sachse, 1992) are
conducted at session 2, 5 and 8.
Study from the participants view. After contaciting the study administration, the
participant's information contained a precise description of the inclusion and exclusion
criteria, the structure of the treatment manual as well as the data collection procedure
including the video recordings. Confidentiality of the collected data is confirmed.
Volontarines of participation is emphasized by the opportunity to terminate the treatment at
every timepoint during treatment and the cancelation of all conducted data. Furthermore, an
insurance for possible negative outcomes of clinical trials is contracted.
Statistical Analysis. In order to handle the hierarchical data structures (sessions at Level
1 nested within patients at Level 2 and therapists at Level 3), hierarchical linear model
(HLM) with time as a within-groups factor and treatment condition as a between-groups factor
will be used for the main research questions. The analyses will be conducted on the
intention-to-treat sample as well as on the completer sample. To investigate if possible
patients' and therapists' effects have an impact to the therapy outcomes, patients' and
therapists' pretreatment characteristics are investigated as outcome predictors at Level 2
and 3. Clinical significance will be defined as (a) a statistically reliable change
according to the Reliable Change Index (RCI), and (b) being within two standard deviations
of a nonclinical group at post-assessment or follow-up (Jacobson & Truax, 1991). All the
analyses will be run by HLM and R packet.
Sample size. Based on a power analysis with G*Power the optimal sample size with an
Alpha-error of 5 %, and a Beta-error of 80% as well as a correlation coefficient of r = .30
of the repeated assessments are 60 participants, i.e. 20 participants in each priming
condition.
;
Allocation: Randomized, Endpoint Classification: Efficacy Study, Intervention Model: Parallel Assignment, Masking: Single Blind (Subject), Primary Purpose: Treatment