Social Interaction Anxiety Scale (SIAS)

Abstract

The Social Interaction Anxiety Scale (SIAS) is a premier 20-item self-report psychometric instrument designed to assess pervasive distress, apprehension, and cognitive disruption experienced during interpersonal exchanges. Developed by Richard P. Mattick and J. Christopher Clarke in 1998, the instrument was conceived alongside its companion instrument, the Social Phobia Scale (SPS), to distinguish between two clinically distinct presentations of Social Anxiety Disorder (SAD): social interaction anxiety (dyadic or group communication, meeting strangers, initiating conversations, talking to authority figures) and scrutiny or performance anxiety (being observed while eating, writing, or speaking in public). The SIAS employs a 5-point Likert response scale ranging from 0 (Not at all characteristic or true of me) to 4 (Extremely characteristic or true of me), yielding a total score between 0 and 80. Psychometric evaluations across diverse clinical, non-clinical, and cross-cultural cohorts demonstrate exceptional internal consistency (Cronbach’s α typically ranging between .88 and .94 in clinical samples, and .86 to .93 in community populations), high test-retest reliability across multiple intervals (r = .86 to .92), and robust convergent and discriminant validity with related constructs such as fear of negative evaluation, behavioral avoidance, depression, and general state-trait anxiety. While originally conceptualized as measuring a single, unidimensional factor of social interaction distress, contemporary structural equation modeling and confirmatory factor analyses frequently demonstrate that three reverse-scored items introduce methodological artifacts, leading researchers to examine bifactor configurations and truncated variants (e.g., SIAS-6). The SIAS remains one of the gold-standard measures in psychiatric diagnostic assessment, clinical trials of pharmacotherapy and cognitive-behavioral therapy (CBT), and longitudinal epidemiological research on social anxiety pathology.

Keywords

Social Interaction Anxiety Scale, SIAS, Social Phobia Scale, Social Anxiety Disorder, Psychometrics, Cognitive Behavioral Therapy, Interaction Anxiety, Factor Analysis, Mattick and Clarke, Scrutiny Fear, Internal Consistency

Authors

The Social Interaction Anxiety Scale was developed by Richard P. Mattick and J. Christopher Clarke. At the time of the scale’s initial validation studies and eventual formal publication in 1998, both researchers were affiliated with the School of Psychiatry and the School of Psychology at the University of New South Wales (UNSW) in Sydney, Australia.

Richard P. Mattick, Ph.D., is a distinguished Australian psychologist, researcher, and Professor of Clinical Psychology. He subsequently served as the Director of the National Drug and Alcohol Research Centre (NDARC) at UNSW. His scholarship spans anxiety disorders, behavioral medicine, clinical psychometrics, and substance use epidemiology, authoring hundreds of peer-reviewed articles and clinical intervention manuals that bridge empirical experimental psychology with diagnostic and therapeutic applications.

J. Christopher Clarke, Ph.D., was a prominent clinical psychologist and academic at the University of New South Wales. Clarke is renowned for his pioneering contributions to behavioral psychotherapy, exposure paradigms, and the experimental analysis of human fear conditioning. His collaborative work with Mattick throughout the late 1980s and 1990s was instrumental in defining contemporary measurement standards for social phobia subtyping, helping transform the diagnostic operationalization of social fears under the third and fourth editions of the Diagnostic and Statistical Manual of Mental Disorders (DSM).

Purpose

The primary clinical and psychometric purpose of the Social Interaction Anxiety Scale (SIAS) is to provide an objective, reliable, and sensitive quantification of the cognitive, affective, and behavioral distress evoked by interpersonal interactions. Prior to the development of the SIAS and SPS, existing instruments—such as the Fear of Negative Evaluation (FNE) Scale and the Social Avoidance and Distress (SAD) Scale—suffered from significant psychometric and conceptual limitations. Many earlier inventories conflated general social unease with depressive withdrawal, lacked situational specificity, or utilized true/false response formats that restricted measurement sensitivity to clinical change.

Mattick and Clarke recognized that social phobia encompasses two distinct situational triggers requiring differential clinical evaluation:

• Interaction Anxiety: Fear and physiological activation triggered when an individual must engage in mutual, dynamic verbal and non-verbal exchanges with another person or group (e.g., starting a conversation, making small talk at a gathering, speaking to an employer or teacher, engaging with an attractive romantic interest).
• Scrutiny/Observation Anxiety: Fear triggered by the prospect or reality of being observed by others while undertaking routine tasks (e.g., eating in public, signing a document while being watched, public speaking), regardless of whether interactive communication is required.

The SIAS was engineered specifically to isolate interaction anxiety. In clinical psychiatry and clinical psychology, the SIAS serves multiple key functions:

• Diagnostic Screening and Triaging: It aids clinicians in distinguishing clinically significant social phobia from subclinical social reticence, non-clinical shyness, or generalized panic spectrum presentations. Clinical cut-off scores (e.g., scores ≥ 34 or ≥ 36) allow rapid triaging into specialized psychiatric treatment pipelines.
• Treatment Planning: By mapping specific interpersonal scenarios (such as difficulty talking to authority figures, initiating friendships, or expressing disagreement), clinicians can formulate tailored behavioral exposure hierarchies and identify target automatic thoughts for cognitive restructuring.
• Treatment Outcome Monitoring: The 5-point Likert format allows the SIAS to detect subtle therapeutic shifts in social comfort, cognitive appraisal, and behavioral approach across weeks of Cognitive Behavioral Therapy (CBT), social skills training, or pharmacotherapy (e.g., SSRIs, SNRIs).
• Basic Psychopathology Research: The SIAS is utilized extensively to model the relationships between social anxiety, attentional biases, post-event rumination, interpretation bias, safety behaviors, and interpersonal functioning in laboratory, neuroimaging, and naturalistic ecological momentary assessment designs.

Psychological Construct

The central psychological construct measured by the SIAS is social interaction anxiety. Under modern cognitive-behavioral and psychiatric formulations, social interaction anxiety is conceptualized as an intense, persistent fear of being judged, scrutinized, rejected, or found inadequate during interpersonal exchanges. Unlike performance situations—where an individual typically has a clearly defined role, predictable structure, and unilateral delivery (such as playing an instrument or delivering a formal lecture)—social interactions are dynamic, reciprocal, unpredictable, and open-ended. This open-ended nature magnifies perceived social danger for socially anxious individuals.

The construct encompasses several distinct cognitive, affective, and behavioral dimensions represented throughout the instrument’s 20 items:

1. Dyadic and Informal Social Exchanges

This facet assesses subjective tension and apprehension when engaged in one-on-one dialogues or informal socializing with peers and acquaintances. Items such as Item 8 (“I feel tense if I am alone with just one other person”), Item 6 (“I tense up if I meet an acquaintance in the street”), and Item 10 (“I have difficulty talking with other people”) tap into the dread of silences, conversational stagnation, and the pressure of immediate, reciprocal conversational demands.

2. Interaction with Authority Figures and Hierarchical Distance

Social anxiety frequently interacts with perceived status differentials. When interacting with authority figures (e.g., managers, university professors, supervisors), the perceived stakes of appearing incompetent or foolish increase dramatically. Item 1 (“I get nervous if I have to speak with someone in authority (teacher, boss, etc.)”) directly evaluates vulnerability to hierarchy-induced evaluation anxiety.

3. Group Dynamics and Mixing Behaviors

Interacting within a collective social context introduces complex monitoring demands. Individuals must navigate multiple social cues, manage physical proximity, and tolerate being the center of group attention. Items measuring this dimension include Item 4 (“I find difficulty mixing comfortably with the people I work with”), Item 7 (“When mixing socially, I am uncomfortable”), Item 18 (“When mixing in a group, I find myself worrying I will be ignored”), and Item 19 (“I am tense mixing in a group”). Notably, Item 18 captures fear of social marginalization and ostracism, which represents a critical cognitive vulnerability in social anxiety disorder.

4. Self-Disclosure, Emotional Intimacy, and Romantic Contexts

Intimacy demands the disclosure of private emotional states, which socially anxious individuals perceive as exposing their intrinsic flaws. Item 3 (“I become tense if I have to talk about myself or my feelings”) captures the inhibition of authentic self-disclosure. Similarly, Item 14 (“I have difficulty talking to attractive persons of the opposite sex”) assesses anxiety elicited in high-stakes evaluative contexts where romantic rejection or physical scrutiny is feared.

5. Assertiveness and Social Friction

Socially anxious individuals often display extreme conflict avoidance due to catastrophized expectations of interpersonal conflict. Item 13 (“I find it difficult to disagree with another’s point of view”) measures the suppression of personal disagreement to appease others and avoid rejection or confrontation.

6. Cognitive Dysregulation and Anticipatory/In-Vivo Catastrophizing

A substantial component of the SIAS measures the internal cognitive chatter that disrupts verbal fluency. Item 12 (“I worry about expressing myself in case I appear awkward”), Item 15 (“I find myself worrying that I won’t know what to say in social situations”), and Item 17 (“I feel I’ll say something embarrassing when talking”) capture anticipatory cognitive processing and the fear of visible behavioral failure.

7. Social Self-Efficacy (Positively Worded Items)

Three items on the SIAS measure perceived ease and competence in establishing connections: Item 5 (“I find it easy to make friends of my own age”), Item 9 (“I am at ease meeting people at parties, etc.”), and Item 11 (“I find it easy to think of things to talk about”). These items are reverse-scored, reflecting social self-efficacy and behavioral approach confidence.

Theoretical Framework

The construction and validation of the SIAS are grounded in cognitive-behavioral, evolutionary, and information-processing theories of social phobia, particularly the landmark models formulated by David M. Clark and Adrian Wells (1995), as well as Ronald M. Rapee and Richard G. Heimberg (1997).

The Clark and Wells Cognitive Model of Social Phobia

The theoretical framework of Clark and Wells (1995) posits that individuals with social anxiety harbor deeply ingrained, dysfunctional assumptions about themselves and their social world. These assumptions fall into three broad categories:

• Excessively high standards for social performance: e.g., “I must always be witty, articulate, and interesting; any hesitation is unacceptable.”
• Conditional beliefs regarding social evaluation: e.g., “If I disagree with someone, they will despise or abandon me” (reflected directly in SIAS Item 13).
• Unconditional negative beliefs about the self: e.g., “I am socially incompetent, boring, and fundamentally flawed.”

When an individual entering a social interaction perceives an evaluative threat, an internal cognitive-attentional program is activated. Attention shifts from the conversational partner or environment toward the self, initiating intensive self-focused monitoring. The individual relies on internal somatic and affective cues (e.g., palpitations, facial warmth, muscle tension) to construct an internal mental representation of how they appear to others—an image that is almost invariably distorted and viewed from an observer perspective. Items on the SIAS, such as Item 12 and Item 17, capture this anticipatory and in-vivo cognitive apprehension regarding self-presentation.

The Rapee and Heimberg Model

Concurrently, Rapee and Heimberg (1997) proposed that socially anxious individuals distribute their attentional resources across two simultaneous channels: self-monitoring (internal physiological sensations and cognitive thoughts) and external monitoring (scanning the social partner for subtle indicators of disapproval, boredom, or judgment). The individual compares their perceived self-presentation against their subjective perception of the external audience’s expectations. Because their subjective standard for what others expect is unrealistically high, a discrepancy is perceived, triggering catastrophic predictions of severe social failure, loss of status, and subsequent avoidance behaviors.

Evolutionary and Ethological Perspectives

The SIAS also aligns with ethological and evolutionary models of human social behavior, such as those proposed by Paul Gilbert (2000). From an evolutionary viewpoint, social anxiety is an adaptive mechanism derived from mammalian dominance hierarchies. The fear of authority figures (Item 1), submissive non-verbal signals like gaze aversion (Item 2: “I have difficulty making eye-contact with others”), and reluctance to voice disagreement (Item 13) reflect evolutionary appeasement displays designed to inhibit direct confrontation with higher-ranking group members and prevent social expulsion.

Validity

Extensive empirical investigations across clinical psychiatric samples, student populations, and community cohorts have established the validity of the SIAS across multiple psychometric paradigms.

Construct and Convergent Validity

Convergent validity is evidenced by strong, statistically significant correlations with other established measures of social fear and behavioral avoidance. In their foundational validation study, Mattick and Clarke (1998) reported that the SIAS exhibited large positive correlations with:

• The Fear of Negative Evaluation (FNE) Scale: correlations typically ranging from r = .65 to .72 in clinical samples.
• The Social Avoidance and Distress (SAD) Scale: correlations between r = .68 and .77.
• The Liebowitz Social Anxiety Scale (LSAS): correlations ranging from r = .70 to .84 across both total and interaction subscale scores.

Furthermore, the SIAS displays moderate-to-high correlations with trait anxiety measures, such as the Spielberger State-Trait Anxiety Inventory (STAI-T) (r ≈ .55 to .65), reflecting the shared neuroticism component underlying general internalizing distress.

Discriminant Validity

Discriminant validity has been rigorously demonstrated by showing that the SIAS differentiates social anxiety disorder from other psychiatric conditions, including agoraphobia, panic disorder, obsessive-compulsive disorder (OCD), and major depressive disorder. Mattick and Clarke (1998) showed that patients with social phobia scored significantly higher on the SIAS (Mean = 34.6, SD = 16.4) than patients diagnosed with agoraphobia with panic attacks (Mean = 22.8, SD = 13.9) or normal community controls (Mean = 18.8, SD = 11.8).

Although social anxiety and depression frequently co-occur, the correlations between the SIAS and depression inventories—such as the Beck Depression Inventory (BDI-II)—typically fall within moderate ranges (r = .35 to .50), confirming that the SIAS does not merely assess general dysphoria or demoralization.

Criterion and Predictive Validity

The SIAS exhibits robust predictive validity in laboratory behavioral assessment tasks (BATs). Research by Heimberg, Mueller, Holt, Mattick, and Clarke (1992) demonstrated that during standardized, unstructured social interaction tests (e.g., initiating conversation with an unknown confederate), individuals with elevated SIAS scores exhibited significantly higher self-reported subjective units of distress (SUDS), elevated observer-rated behavioral anxiety, and shorter conversational duration prior to termination. Moreover, post-treatment reductions in SIAS scores consistently correlate with objective improvements in interpersonal functioning and decreases in behavioral safety maneuvers.

Clinical Sensitivity and Cut-off Scores

Diagnostic utility analyses, including Receiver Operating Characteristic (ROC) curves, have established operational cut-off criteria:

• Heimberg et al. (1992) and Peters (2000): Identified a cut-off score of 34 as maximizing sensitivity (.82) and specificity (.85) for differentiating patients meeting DSM criteria for Social Anxiety Disorder from non-clinical community controls.
• A cut-off score of 43 is widely applied in clinical trial settings to identify individuals with the generalized subtype of social phobia, who exhibit pervasive interpersonal impairment across multiple domains.

Reliability

The SIAS possesses robust reliability indices across varying populations, research laboratories, and linguistic translations.

Internal Consistency

In the seminal publication by Mattick and Clarke (1998), the scale demonstrated exceptional internal consistency:

• Clinical Social Phobia Sample (N = 243): Cronbach’s α = .88.
• Clinical Agoraphobia Sample (N = 65): Cronbach’s α = .89.
• Undergraduate University Sample (N = 801): Cronbach’s α = .94.
• Community Sample (N = 225): Cronbach’s α = .93.

Subsequent psychometric investigations have replicated these findings. For instance, in a large clinical evaluation by Heimberg et al. (1992), Cronbach’s alpha reached .93 in an outpatient social anxiety cohort. Contemporary evaluations calculating McDonald’s omega (ω) frequently report values between .89 and .93, confirming that the high alpha coefficient is not merely an artifact of tau-equivalence violations.

Test-Retest Reliability

Temporal stability of the SIAS has been confirmed across diverse test-retest intervals in populations not receiving active therapeutic interventions:

• Mattick and Clarke (1998): Reported a 4-week test-retest reliability coefficient of r = .92 in an undergraduate non-clinical sample.
• Clinical Waitlist Controls: Across an 8-to-12-week waitlist period, test-retest correlations have ranged from r = .86 to r = .90, demonstrating that spontaneous remission or score drift is minimal in the absence of treatment.

Standard Error of Measurement and Sensitivity to Change

The Standard Error of Measurement (SEM) for the SIAS is typically estimated between 3.5 and 4.2 score units, depending on sample dispersion. This relatively low measurement error facilitates the calculation of the Reliable Change Index (RCI). A shift of approximately 8 to 10 points on the SIAS can be interpreted with 95% statistical confidence as reflecting genuine, clinically meaningful change rather than random psychometric fluctuation.

Factor Analysis

The latent dimensionality of the SIAS has been the subject of extensive psychometric investigation and analytical debate within quantitative psychology.

Initial Unidimensional Formulation

Mattick and Clarke (1998) originally subjected the 20 items of the SIAS to exploratory factor analysis (EFA) with principal axis factoring and varimax rotation. Their initial findings indicated that the instrument was predominantly unidimensional, with the primary factor accounting for the vast majority of common variance (over 40%). High factor loadings (ranging between .50 and .78) were reported across nearly all items, leading the authors to recommend summing all items into a single composite social interaction anxiety score.

The Reverse-Scored Items and Method Effects

Subsequent confirmatory factor analyses (CFA) conducted in independent laboratories questioned this strict unidimensional structure. A primary issue highlighted in psychometric literature involves the three reverse-scored items: Item 5 (“I find it easy to make friends of my own age”), Item 9 (“I am at ease meeting people at parties, etc.”), and Item 11 (“I find it easy to think of things to talk about”).

Studies by Rodebaugh et al. (2004, 2007) and Carleton et al. (2009) established that single-factor CFA models fitting all 20 items invariably produced suboptimal fit indices, typically characterized by an elevated Root Mean Square Error of Approximation (RMSEA > .08) and lower Comparative Fit Index values (CFI < .90). When examined via exploratory structural equation modeling, the three reverse-worded items consistently split off to form a secondary factor.

Rodebaugh and colleagues demonstrated that this secondary factor does not represent a substantive psychological construct (such as an independent “extraversion” or “social competence” dimension), but rather a method effect stemming from cognitive processing artifacts common to reverse-keyed survey items. When these three items are removed, or when method effects are explicitly modeled using bifactor or correlated-trait/uncorrelated-method (CTUM) designs, fit indices improve substantially:

• Standard Single-Factor Model (all 20 items): χ²/df = 4.12, CFI = .88, RMSEA = .085
• Correlated Trait-Method Model (accounting for reversed items): χ²/df = 2.14, CFI = .96, RMSEA = .048
• 17-Item Straightforward Single-Factor Model (excluding Items 5, 9, and 11): χ²/df = 2.32, CFI = .97, RMSEA = .049

Short-Form Derivations (SIAS-6)

Because of these factor-analytic complexities and the need for brief screening instruments in primary care settings, Peters et al. (2012) utilized item response theory (IRT) and CFA to validate the SIAS-6. This 6-item short form consists entirely of straightforwardly worded items exhibiting the highest information curves and latent trait discrimination parameters, retaining high concordance (r > .90) with the full 20-item instrument.

Instrument / Measurement Tool

The complete psychometric details, structural characteristics, and administrative parameters of the Social Interaction Anxiety Scale are detailed below:

• Instrument Name: Social Interaction Anxiety Scale (SIAS)
• Companion Scale: Social Phobia Scale (SPS)
• Format: Self-administered paper-and-pencil or digital questionnaire
• Target Population: Adults and adolescents (ages 16+) presenting with social anxiety, anxiety spectrum symptoms, or participating in clinical and epidemiological research
• Reading Level: Estimated at the 6th to 8th-grade reading level (Flesch-Kincaid)
• Completion Time: Approximately 5 to 10 minutes
• Number of Items: 20 items
• Response Scale: 5-point Likert scale rated from 0 to 4:
  • 0 = Not at all characteristic or true of me
  • 1 = Slightly characteristic or true of me
  • 2 = Moderately characteristic or true of me
  • 3 = Very characteristic or true of me
  • 4 = Extremely characteristic or true of me
• Scoring and Transformation Rules:
  • Straightforward Items: Items 1, 2, 3, 4, 6, 7, 8, 10, 12, 13, 14, 15, 16, 17, 18, 19, and 20 are scored directly as marked (0, 1, 2, 3, or 4).
  • Reverse-Scored Items: Items 5, 9, and 11 are reverse-scored prior to calculating the total sum:
    • A rating of 0 becomes 4
    • A rating of 1 becomes 3
    • A rating of 2 remains 2
    • A rating of 3 becomes 1
    • A rating of 4 becomes 0
  • Total Score Calculation: Sum all 20 individual item scores (after reversing Items 5, 9, and 11). Theoretical score range is from 0 to 80.
• Clinical Interpretation Guidelines:
  • 0 – 17: Minimal or non-clinical social interaction anxiety (typical range for non-anxious community populations; non-clinical sample mean ≈ 18.8, SD ≈ 11.8).
  • 18 – 33: Mild to moderate social anxiety; may indicate shyness, situational reticence, or subthreshold social fear without pervasive occupational or academic impairment.
  • 34 – 42: Moderate to elevated social anxiety; scores at or above the established clinical threshold of 34 suggest probable Social Anxiety Disorder (Social Phobia), warranting formal clinical diagnostic evaluation.
  • 43 – 80: Severe to extreme social interaction anxiety; scores ≥ 43 are highly characteristic of generalized social phobia, reflecting extensive interpersonal distress, social avoidance, and marked functional disability.

Permissions & Fee and Test Year

The Social Interaction Anxiety Scale was developed by Richard P. Mattick and J. Christopher Clarke during the late 1980s and formally published in peer-reviewed form in 1998 in the scientific journal Behaviour Research and Therapy.

Licensing and Accessibility: The SIAS is considered an open-access psychometric instrument for clinical, educational, and academic research purposes. The scale items and scoring guidelines were published directly within the 1998 validation article to facilitate widespread empirical application. Researchers and licensed clinicians are generally permitted to administer, reproduce, and score the SIAS without purchasing proprietary licenses or paying individual per-administration royalties, provided that proper scholarly attribution is accorded to the original authors and the publishing journal.

Commercial utilization, distribution within proprietary clinical assessment software systems, or inclusion in monetized corporate health platforms typically requires formal permission from the copyright holders (Elsevier Science Ltd. / the authors). Clinicians and research investigators are advised to verify local institutional review board (IRB) requirements and confirm licensing agreements when deploying the tool within large-scale commercial pharmaceutical trials.

References

• Carleton, R. N., Collimore, K. C., Asmundson, G. J. G., McCabe, R. E., Rowa, K., & Antony, M. M. (2009). Refining and validating the Social Interaction Anxiety Scale and Social Phobia Scale: The SIAS-6 and the SPS-6. Psychological Assessment, 21(1), 71–81. https://doi.org/10.1037/a0014849
• Clark, D. M., & Wells, A. (1995). A cognitive model of social phobia. In R. G. Heimberg, M. R. Liebowitz, D. A. Hope, & F. R. Schneier (Eds.), Social phobia: Diagnosis, assessment, and treatment (pp. 69–93). The Guilford Press.
• Gilbert, P. (2000). The relationship of shame, social anxiety and depression: The role of the evaluation of social rank. Clinical Psychology & Psychotherapy, 7(3), 174–189. https://doi.org/10.1002/1099-0879(200007)7:3<174::AID-CPP236>3.0.CO;2-U
• Heimberg, R. G., Mueller, G. P., Holt, C. S., Mattick, R. P., & Clarke, J. C. (1992). Assessment of anxiety in social situations and examination of the Social Phobia Scale and Social Interaction Anxiety Scale. Behavior Therapy, 23(1), 53–73. https://doi.org/10.1016/S0005-7894(05)80308-9
• Mattick, R. P., & Clarke, J. C. (1998). Development and validation of measures of social phobia scrutiny fear and social interaction anxiety. Behaviour Research and Therapy, 36(4), 455–470. https://doi.org/10.1016/S0005-7967(97)10031-6
• Peters, L. (2000). Discriminant validity of the Social Phobia and Social Interaction Anxiety Scales. Behaviour Research and Therapy, 38(9), 943–950. https://doi.org/10.1016/S0005-7967(99)00130-1
• Peters, L., Sunderland, M., Andrews, G., Rapee, R. M., & Mattick, R. P. (2012). Development of a short form of the Social Interaction Anxiety Scale and the Social Phobia Scale. Psychological Assessment, 24(1), 66–76. https://doi.org/10.1037/a0024544
• Rapee, R. M., & Heimberg, R. G. (1997). A cognitive-behavioral model of anxiety in social phobia. Behaviour Research and Therapy, 35(8), 741–756. https://doi.org/10.1016/S0005-7967(97)00022-3
• Rodebaugh, T. L., Woods, C. M., & Heimberg, R. G. (2007). The reverse of social anxiety is not social competence: Investigating the reverse-scored items of the Social Interaction Anxiety Scale. Psychotherapy and Psychosomatics, 76(4), 224–232. https://doi.org/10.1159/000101501
• Rodebaugh, T. L., Woods, C. M., Thissen, D. M., Heimberg, R. G., Chambless, D. L., & Rapee, R. M. (2004). More information from fewer questions: The factor structure and item properties of the Social Phobia Scale and the Social Interaction Anxiety Scale. Psychological Assessment, 16(2), 169–181. https://doi.org/10.1037/1040-3590.16.2.169

Items of the Scale