Social Interaction Anxiety Scale (SIAS)

Abstract

The Social Interaction Anxiety Scale (SIAS) is a specialized 20-item self-report questionnaire developed by R. P. Mattick and J. C. Clarke in 1989. This instrument is designed to assess the subjective distress, fear, and avoidance associated specifically with general social interactions and conversational engagement, distinguishing it from the fear of scrutiny or public performance. The SIAS is a cornerstone tool in the assessment and monitoring of Social Anxiety Disorder (SAD), providing a reliable measure of the interpersonal and conversational anxiety component of the disorder.

Keywords

Social Interaction Anxiety Scale, SIAS, Social Anxiety Disorder, Social Interaction Anxiety, Social Phobia, Assessment, Self-Report, Clinical Psychology, Conversational Anxiety.

Authors

R. P. Mattick, J. C. Clarke.

Purpose

The primary purpose of the SIAS is to provide a focused and quantifiable measure of anxiety experienced during interpersonal exchanges, such as initiating conversations, maintaining dialogue, or interacting with unfamiliar individuals. It was designed to measure the “interactional” component of social anxiety, which is often contrasted with performance fears (measured by instruments like the Social Phobia Scale, SPS).

The scale serves multiple functions in clinical and research settings: it aids in the differential diagnosis of social anxiety, tracks the severity of interaction-related symptoms, and is widely utilized as an outcome measure to evaluate the efficacy of psychological interventions, particularly Cognitive Behavioral Therapy (CBT).

Construct

The SIAS measures the psychological construct of Social Interaction Anxiety. This construct reflects an individual’s chronic worry, apprehension, and distress stemming from potential negative outcomes during social exchanges. The items specifically target internal concerns about appearing awkward, being unable to generate conversation topics, difficulty asserting oneself, and feeling tense when alone with another person or mixing in a group.

The scale captures the cognitive component (worry about what to say) and the affective component (tension and discomfort) inherent in social situations, providing a detailed profile of the individual’s subjective experience of interpersonal fear.

Validity

The SIAS demonstrates strong psychometric properties, confirmed across numerous validation studies. It exhibits excellent convergent validity, showing high correlation with other established measures of social anxiety, such as the Liebowitz Social Anxiety Scale (LSAS) and the Social Phobia Scale (SPS), particularly in clinical populations diagnosed with SAD.

Furthermore, the scale possesses good discriminant validity, successfully distinguishing social interaction anxiety from generalized anxiety disorder or depression, suggesting it measures a unique aspect of psychopathology. Its clinical utility is enhanced by its sensitivity to change, making it an effective instrument for measuring treatment response, especially reductions in anxiety following interventions like guided exposure and cognitive restructuring.

Reliability

The reliability of the SIAS is consistently high. Studies across diverse samples—both clinical and non-clinical—report high internal consistency, with Cronbach’s alpha coefficients routinely exceeding 0.90. This high alpha value confirms that the 20 items are measuring the same underlying construct coherently.

In addition to strong internal consistency, the SIAS has demonstrated acceptable to strong test-retest reliability over periods ranging from a few weeks to several months, indicating that the scale provides stable scores for individuals whose social anxiety symptoms have not undergone significant clinical change.

Factor Analysis

Initially conceptualized as a unidimensional scale, factor analysis of the SIAS typically supports a robust single factor representing global social interaction anxiety. This single factor structure allows for the use of a straightforward total score (ranging from 0 to 80) to indicate overall severity.

Although some subsequent research has occasionally suggested the presence of minor sub-factors, such as “Social Discomfort” or “Initiating Interaction,” the primary clinical and research application relies on the total score, affirming its strong overall measurement of the core construct.

Instrument

Test Type: Self-report questionnaire / Clinical assessment tool

Format: 20 items scored on a 5-point Likert Scale (0 = Not at all characteristic or true of me; 4 = Extremely characteristic or true of me). Total scores range from 0 to 80, with higher scores indicating greater social interaction anxiety.

Language Available: English (original), with validated translations available in numerous languages, including German, Spanish, and Dutch.

Population Group: Clinical and non-clinical adults and adolescents.

Age Group: Typically 16 years and older.

Population Details: Primarily used in individuals seeking treatment for or diagnosed with Social Anxiety Disorder (SAD) or specific social phobias, as well as general population studies on social discomfort.

Test Methodology: Self-administered paper-and-pencil or computer-based questionnaire. Completion time is typically 5 to 10 minutes.

Keywords

Psychometrics, Self-report, Likert Scale, CBT outcome, Unidimensional, Scrutiny Fear, Conversational Anxiety, Test-retest reliability.

Authors

Author ORCID Identifier: Information not provided in source.

Affiliation Email addresses: Information not provided in source.

Correspondence Address: Information not provided in source.

Permissions & Fee and Test Year

The scale was initially developed and published in 1989 (Mattick & Clarke). The definitive validation paper was published in 1998. While often used freely for academic research, clinical or commercial applications may require formal permission from the authors or copyright holders. The original PDF can be downloaded here: http://www.bhevolution.org/public/document/sias.pdf. Additional resources are referenced in the provided bibliography.

Reference’s

• Mattick‚ R. P.‚ & Peters‚ L. (1988). Treatment of severe social phobia: Effects of guided exposure with and without cognitive restructuring. Journal of Consulting and Clinical Psychology‚ 56‚ 251-260.
• Mattick‚ R. P.‚ Peters‚ L.‚ & Clarke‚ J. C. (1989). Exposure and cognitive restructuring for social phobia: A controlled study. Behavior Therapy‚ 20‚ 3-23.
• Mattick‚ R. P.‚ & Clarke‚ J. C. (1989). Development and validation of measures of social phobia scrutiny fear and social interaction anxiety. Unpublished manuscript.
• Brown‚ Elissa J.‚ Turovsky‚ Julia.‚ Heimberg‚ Richard G. et al. (1997). Validation of the Social Interaction Anxiety Scale and the Social Phobia Scale across the anxiety disorders. Psychological Assessment 9(1):21-27
• 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
• Osman‚ Augustine; Gutierrez‚ Peter M.‚ Barrios‚ Francisco X.‚ Kopper‚ Beverly A.‚ Chiros‚ Christine E. (1998). Journal of Psychopathology and Behavioral Assessment. 20 (3): 249–264.
• Peters‚ Lorna. (2000). Discriminant validity of the Social Phobia and Anxiety Inventory (SPAI)‚ the Social Phobia Scale (SPS) and the Social Interaction Anxiety Scale (SIAS). Behaviour Research and Therapy‚ 38(9): 943–950
• Fergus‚ Thomas A.‚ Valentiner‚ David P.‚ McGrath‚ Patrick B.‚ Gier-Lonsway‚ Stephanie L.‚ Kim‚ Hyun-Soo (2012-05-01). “Short Forms of the Social Interaction Anxiety Scale and the Social Phobia Scale”. Journal of Personality Assessment. 94 (3): 310–320.
• Blanc‚ Allura L. Le‚ Bruce‚ Laura C.‚ Heimberg‚ Richard G.‚ Hope‚ Debra A.‚ Blanco‚ Carlos‚ Schneier‚ Franklin R.‚ Liebowitz‚ Michael R. (2014-06-01). “Evaluation of the Psychometric Properties of Two Short Forms of the Social Interaction Anxiety Scale and the Social Phobia Scale”. Assessment. 21 (3): 312–323
• Leary‚ Mark R.‚ Jongman-Sereno‚ Katrina P.‚ and Diebels‚ Kate J. (2015). Measures of Concerns with Public Image and Social Evaluation. in Gregory Boyle‚ Donald H. Saklofske and Gerald Matthews.‚ Measures of Personality and Social Psychological Constructs. Elsevier‚ Pages 448–473

Items of the Social Interaction Anxiety Scale (SIAS)

Social Interaction Anxiety Scale (SIAS)

Mattick and Clarke ‚1989

1. I get nervous if I have to speak with someone in authority (teacher‚ boss‚ etc.).
2. I have difficulty making eye contact with others.
3. I become tense if I have to talk about myself or my feelings.
4. I find it difficult to mix [mixing] comfortably with the people I work with.
5. I find it easy to make friends my own age.
6. I tense up if I meet an acquaintance in the street.
7. When mixing socially‚ I am uncomfortable.
8. I feel tense if I am alone with just one other person.
9. I am at ease meeting people at parties‚ etc.
10. I have difficulty talking with other people.
11. I find it easy to think of things to talk about.
12. I worry about expressing myself in case I appear awkward.
13. I find it difficult to disagree with another’s point of view.
14. I have difficulty talking to attractive persons of the opposite sex.
15. I find myself worrying that I won’t know what to say in social situations.
16. I am nervous mixing with people I don’t know well.
17. I feel I’ll say something embarrassing when talking.
18. When mixing in a group‚ I find myself worrying I will be ignored.
19. I am tense mixing in a group.
20. I am unsure whether to greet someone I know only slightly.

Scoring Instructions:

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.

Reverse Items: 5‚ 9‚ 11