AI-Based CBT Chatbot for Adolescent Social Anxiety

The Negative Cognitive Processing Bias Scale for Adolescents (NCPBSA) is used to measure the three negative cognitive processing biases of attention, interpretation, and memory in adolescents (Feng et al., 2024). NCPBSA consists of 15 items (for example, "When several classmates are discussing issues that I don't know, I feel that they are excluding me"), and uses a 4-point scoring method (1 = "completely not conforms", 4 = "extremely conforms"). The total score ranges from 15 to 60， and the higher the score, the more severe the negative cognitive processing bias.

The Social Behaviour Questionnaire (SBQ) is used to measure the frequency of safe behaviors that individuals employ when feeling anxious in social situations (Clark, 2005). SBQ consists of 28 items (for example, "Avoid making eye contact with others"), and uses a 4-point scoring system (0 = "Never", 3 = "Always"). The total score ranges from 0 to 84, with higher scores indicating a higher frequency of using safe behaviors.

The Social Skill Inventory (SSI) is used to measure individuals' self-assessment of their social skills (Riggio, 1986). Based on previous studies (Okano \& Nomura, 2023; Strahan, 2003), this study only selected the Social Control subscale (SC) to evaluate the skills of playing an appropriate role and effectively presenting oneself in different social situations, as it is significantly associated with lower self-evaluations among individuals with social anxiety. The SC consists of 15 items (for example, "I find it difficult to look at others when discussing personal matters"), using a 5-point scoring method (1 = "Not at all like me", 5 = "Extremely like me"). The total score ranges from 15 to 75, with a higher score indicating poorer social skills.

The Cognitive Emotion Regulation Questionnaire (CERQ) is used to measure the cognitive emotion regulation strategies employed by individuals when dealing with stressful situations (Garnefski \& Kraaij, 2006). CERQ encompasses five adaptive strategies (acceptance, positive re-engagement, planned re-engagement, positive reappraisal, and perspective transformation) and four non-adaptive strategies (self-blame, rumination, catastrophic thinking, and blaming others). Referencing previous studies (Liu et al., 2025), this study only selects the rumination subscale to assess rumination thinking. The rumination subscale consists of 2 items (for example, "I repeatedly think about how I felt in that situation"), using a 5-point scoring method (1 = "Never", 5 = "Always"). The total score ranges from 2 to 10, with a higher score indicating stronger rumination thinking.

The Brief Experiential Avoidance Questionnaire (BEAQ) is used to measure an individual's dispositional avoidance, that is, the tendency to use avoidance behaviors in painful situations (Gámez et al., 2014). BEAQ covers six dimensions: behavioral avoidance, pain aversion, procrastination, distraction/inhibition, repression/ denial, and pain persistence, and includes 15 items (for example, "When feeling embarrassed, I will immediately do something to eliminate this feeling"). It uses a 6-point scoring method (1 = "Strongly Disagree", 6 = "Strongly Agree"). The total score ranges from 15 to 90, and the higher the score, the stronger the tendency for experiential avoidance.

The Emotion Regulation Questionnaire (ERQ) is used to measure the frequency with which individuals employ emotion regulation strategies (Gross \& John, 2003). ERQ covers two dimensions: cognitive reappraisal and expressive suppression. Based on previous studies, this research only selects the Expressive Suppression (ES) subscale, which consists of 4 items (for example, "I control my emotions and do not let them show.") and uses a 7-point scoring method (1 = "completely not conforms"， 7 = "completely conforms"). The total score ranges from 4 to 28， and the higher the score， the higher the frequency of expressive suppression usage.

At baseline and post-intervention, participants completed the Trier Social Stress Test (TSST), which includes a 5-minute preparation period, a 5-minute impromptu speech, and a 3-minute mental arithmetic task designed to simulate a high-pressure social evaluation scenario. Throughout the test, a portable physiological polygraph was used to continuously record heart rate (HR) as an indicator of sympathetic nervous system arousal.

At baseline and post-intervention, participants completed the Trier Social Stress Test (TSST), which includes a 5-minute preparation period, a 5-minute impromptu speech, and a 3-minute mental arithmetic task designed to simulate a high-pressure social evaluation scenario. Throughout the test, a portable physiological polygraph was used to continuously record Heart Rate Variability (HRV). Analyses focused on high-frequency (HF) power and the low-frequency/high-frequency (LF/HF) ratio, which serve as core indicators of parasympathetic activity and autonomic balance, respectively, reflecting the flexibility and stability of emotional regulation.

At baseline and post-intervention, participants completed the Trier Social Stress Test (TSST), which includes a 5-minute preparation period, a 5-minute impromptu speech, and a 3-minute mental arithmetic task designed to simulate a high-pressure social evaluation scenario. Throughout the test, a portable physiological polygraph was used to continuously record Electrodermal Activity (EDA). As a direct and sensitive indicator of sympathetic nervous system activation, EDA reflects emotional sweating responses.