Interaction Anxiousness Scale

Abstract

The Interaction Anxiousness Scale (IAS), developed by Mark R. Leary in 1983, is a widely utilized psychometric scale designed to measure individual differences in the tendency to experience anxiety and discomfort specifically during social interactions. This 15-item self-report instrument assesses the degree to which individuals feel nervous or tense in various interpersonal situations, distinguishing general interaction apprehension from related but distinct constructs like shyness or fear of negative evaluation. The IAS is a foundational tool for researchers studying the trait component of social anxiety.

Keywords

Social anxiety, interaction anxiety, Interaction Anxiousness Scale, IAS, social phobia, self-report, shyness, personality assessment.

Authors

Mark R. Leary, Robin M. Kowalski.

Purpose

The primary purpose of the Interaction Anxiousness Scale is to provide a reliable and concise measure of the predisposition to experience anxiety when engaging in or anticipating social interactions. It aims to quantify the frequency and intensity of feelings of nervousness across a variety of common interpersonal settings, such as casual gatherings, speaking to authority figures, or interacting with unfamiliar individuals.

Unlike broader measures of trait anxiety, the IAS specifically targets the discomfort arising from the act of interaction itself, making it a valuable tool for research in social psychology and clinical screening for interaction-related apprehension.

Construct

The IAS measures Social Anxiousness, which Leary (1983) defined as a general, chronic disposition to experience negative emotional states, particularly nervousness and tension, during social encounters. This construct is closely related to, but conceptually distinct from, social anxiety disorder or social phobia, serving as a measure of the trait-level tendency toward interaction-related distress.

The underlying theory suggests that highly anxious individuals are preoccupied with potential negative outcomes or evaluations during interactions, leading to avoidance behaviors or heightened physiological arousal. The 15 items capture this apprehension across varied social contexts, reflecting the pervasive nature of the construct.

Validity

Extensive research, notably the 1993 study by Leary and Kowalski, has established strong psychometric properties for the IAS. Criterion-related validity has been demonstrated through the scale’s ability to predict behaviors consistent with social apprehension, such as reduced initiation of conversations or avoidance of social events. Furthermore, the IAS shows high convergent validity with other established measures of social anxiety and shyness, such as the Social Avoidance and Distress Scale (SAD) and the Personal Report of Communication Apprehension (PRCA).

Conversely, the scale maintains good discriminant validity, showing weaker correlations with measures of general anxiety (non-social) or trait neuroticism, confirming that it specifically targets the interaction component of anxiety rather than global distress.

Reliability

The IAS exhibits excellent internal consistency. Across multiple studies in diverse populations, the internal reliability coefficient, typically measured using Cronbach’s alpha, consistently exceeds .85, indicating that the 15 items reliably measure the same underlying construct. The original 1983 validation study reported high alpha values, confirming the homogeneity of the scale items.

Test-retest reliability is also generally strong, demonstrating the stability of the interaction anxiousness trait over time, suggesting that the scale measures a stable personality disposition rather than a transient emotional state.

Factor Analysis

Initial principal components analysis and subsequent confirmatory factor analyses of the IAS generally support a strong, unidimensional structure. Although some minor factors related to specific types of interaction (e.g., interactions with authority figures vs. peers) may emerge, the scale is robustly interpreted as measuring a single, overarching construct of interaction anxiousness. This clear factor structure contributes to its ease of scoring and interpretation in both research and applied settings.

Instrument

Test Type: Psychometric scale; Self-report questionnaire.

Format: 15 items scored on a 5-point Likert scale (1 = Not at all characteristic of me; 5 = Extremely characteristic of me). Scoring requires reversing specified items (2, 3, 6, 10, 15) to ensure higher scores indicate greater anxiety.

Language Available: Primarily English (validated translations may exist in academic literature).

Population Group: Adolescents and Adults.

Age Group: 16 years and older.

Population Details: Originally validated on university student samples, but widely used across the general population for assessing trait social anxiety.

Test Methodology: Paper-and-pencil or computerized administration. Total score calculation involves summing the responses across all 15 items (after reversal).

Keywords

Trait anxiety, personality assessment, social phobia screening, Leary, Kowalski, interpersonal discomfort, convergent validity.

Authors

Author ORCID Identifier: Not publicly specified for this instrument.

Affiliation Email addresses: Mark R. Leary (Duke University, Department of Psychology).

Correspondence Address: Department of Psychology, Duke University, Durham, NC, USA.

Permissions & Fee and Test Year

The original scale was published in 1983. The IAS is generally considered a freely available instrument for non-commercial academic research and educational purposes. Researchers are typically required to cite the original publication (Leary, 1983) and the validity study (Leary & Kowalski, 1993) when using the scale. No formal fee is typically associated with its use in scholarly contexts.

Reference’s

• Leary, Mark R. (1983). Social Anxiousness: The Construct and Its Measurement. Journal of Personality Assessment, 47: 66-75.

• Leary, Mark R., & Kowalski, Robin M. (1993). The Interaction Anxiousness Scale: Construct and Criterion-Related Validity. Journal of Personality Assessment, 61: 136-146.

• Leary, R.M. & Kowalski, N.R. (1995). Social Anxiety. New York: The Guilford Press.

• The instrument is available online at: http://people.duke.edu/ch‎arleary/scales.html

Items of the Interaction Anxiousness Scale

IMPORTANT: The following scale items must be preserved in their original language and must not be changed in any way.

Scoring Key:

• 1 = Not at all characteristic of me.

• 2 = Slightly characteristic of me.

• 3 = Moderately characteristic of me.

• 4 = Very characteristic of me.

• 5 = Extremely characteristic of me.