The dynamic interaction between experiential avoidance, cognitive avoidance, perceived control and social anxiety symptomology

Avoidance plays a central role in the onset and maintenance of social anxiety
disorder (SAD). Specifically, experiential avoidance (EA) and cognitive
avoidance (CA) are thought to be strategies to decrease anxiety toward
social-evaluative threat No study investigates the combined role of both types
of avoidance. Moreover, perceived control is another important vulnerability
factor in SAD. Lower levels of perceived control are associated with higher
anxiety symptoms, and it has been identified as a possible mechanism of change
in CBT treatment. Perceived control has already been shown to interact with
either EA or CA in other anxiety disorders such as panic disorder and
generalized anxiety disorder. This interaction has not yet been studied in SAD
even though it is highly likely to exist.
The current literature on SAD assumes largely static traits and uses static
data (e.g., based on group means). However, it is likely that constructs such
as symptom severity, EA, CA and perceived control are not static, but rather
fluctuate over time due to the change in the individuals' social environment
for example. Therefore, a method that allows the data collection and analysis
of intensive longitudinal data can shed light on the dynamic interaction
effects between EA, CA and perceived control on social anxiety symptom severity
is preferred over the usual static methods but is thus far underused.

The goal of the study is 1) showing that EA, CA and perceived control are not
stable but of dynamic nature and interact in predicting social anxiety symptom
severity, 2) identifying possible mechanisms of change of CBT (the exact
working of which is so far relatively unknown in SAD) and to contribute
knowledge on how to personalize treatment based on the dynamics of the
predictors.

This is an observational study with a longitudinal design. This design is
suitable to observe daily fluctuations in social anxiety symptoms, avoidance
and perceived control over the course of treatment.

Two assessments including self-reports (LSAS, SIAS, BEAQ, CBAS, & ACQ) will be
administered at baseline (T1; before start of treatment) and post-treatment
(T2; immediately after treatment). In addition, experience sampling method
(ESM) will be used to collect intensive longitudinal data for a period of 18
weeks: before treatment (two-week baseline assessments), during the course of
treatment (14 weeks), and after treatment (two-week post-treatment
assessments). This intensive longitudinal data will be gathered in the form of
a short questionnaire (7 questions) which participants can fill out on their
phone, twice a day (once in the morning, once in the evening).

Note: the LSAS is already part of the usual intake at the Pro Persona clinic
before treatment starts.

There is no risk involved in the daily assessments (neither in the baseline-
and follow-up questionnaires). The only burden to participants is the time
investment of about 4-6 minutes per day. According to the NFU brochure
'Kwaliteitsborging mensgebonden onderzoek 2.0', the overall risk classification
of this study is 'negligible risk'.