Table 2 Overview of data collection

Objective 1: Efficacy

 Primary outcomes

  Social Phobia Anxiety Inventory – brief (SPAI-18) 

x

x

x

x

x

  Liebowitz Social Anxiety Scale – Children & Adolescents (LSAS-CA) – Avoidance subscale 

x

x

x

x

x

  BAT – Peak anxiety (SUDs) 

x

-

x

-

-

 Secondary outcomes

  Liebowitz Social Anxiety Scale – Children & Adolescents (LSAS-CA) – Fear subscale

x

x

x

x

x

  Social Phobia Weekly Summary Scale (SPWSS)

x

x

(weekly sessions)

x

x

x

  Brief resilience scale (BRS)

x

-

x

x

x

  Multidimensional Adolescent Functioning Scale (MAFS)

x

-

x

x

x

  Revised children’s anxiety and depression scale (RCADS)

x

-

x

x

x

  Self-efficacy questionnaire for children (SEQ-C) – social subscale 

x

x

x

x

x

  Adolescent social cognitions questionnaire (ASCQ)

x

-

x

x

x

Exploratory outcomes

  BAT – Anticipatory anxiety (SUDs), heart rate mean & variability, and skin conductance

x

-

x

-

-

Objective 2: Mechanisms

(weekly sessions)

 Threat expectancy likelihood, threat occurrence, surprise, relief, pleasantness of relief, adjusted threat expectancy likelihood (VASs; to measure expectancy violation and change)

x

 SUDs to measure within and between session habituation 

x

 Self-efficacy (VAS)

x

Objective 3: Predictors

 Behavioral inhibition system / behavioral activation system (BIS/BAS)

x

 Experiences in Close Relationship Scale – Relationship Structures (ECR-RS)

x

 Immersive Tendency Questionnaire (ITQ) – subscale Involvement

x

 Unified Theory of Acceptance and Use of Technology (UTAUT) -

Subscales: Attitude & expectancies towards VR

x

 Preference to treatment (TP) – binary 

x

 Experience with VR & games, motivation, need for relatedness/connection, openness to experience (VASs)

x

 Working Alliance Inventory–Short Form (WAI-S)

x

(Session 2 & 6)

 Credibility and Expectancy Questionnaire (CEQ)

x

(Session 1)

Objective 4: Acceptability 

 Client Satisfaction Questionnaire (CSQ-8)

x

 Difficulty, usefulness/relevance, safety behaviors related to exposure, and motivation to participate in the next session (VASs)

x

(weekly sessions)

 Semi-structured interview 

x