Inventory of Interpersonal Situations (IIS)

Abstract

The Inventory of Interpersonal Situations (IIS)—originally developed and standardized in the Netherlands as the Inventarisatielijst Omgaan met Anderen (IOA) by C. M. J. (Rien) Van Dam-Baggen and Floris W. Kraaimaat (1987, 1999)—is an internationally validated, dual-dimensional psychometric assessment designed to assess social anxiety, assertive behavior, and social competence in clinical and non-clinical adult populations. Comprising 35 carefully selected social interaction items, the inventory uniquely evaluates two distinct operational components for each interpersonal scenario: subjective emotional distress or discomfort (Discomfort Scale, rated from 1 = "none" to 5 = "very much") and behavioral execution rate or actual performance (Frequency Scale, rated from 1 = "never" to 5 = "always"). Through extensive exploratory and confirmatory factor analyses, the instrument yields five clinically robust subscales across both dimensions: (1) Giving Criticism and Standing Up for One’s Rights, (2) Expressing Personal Opinions, (3) Positive Assertion and Giving/Receiving Compliments, (4) Initiating Contact, and (5) Refusing Requests and Setting Boundaries. Psychometric evaluations across psychiatric outpatients with social anxiety disorder (social phobia), general psychiatric controls, and community normative samples demonstrate exceptional internal consistency (Cronbach’s alpha ranging from .86 to .96 across composite scales and subscales) and strong test-retest reliability ($r > .80$). Construct, convergent, and discriminant validities are firmly supported through systematic correlations with standardized assertiveness measures, behavioral avoidance tests, and clinician ratings. As an empirically sound self-report instrument, the IIS plays a vital role in differential diagnosis, functional behavioral analyses, and evaluating treatment efficacy in cognitive-behavioral therapy and social skills training.

Keywords

Inventory of Interpersonal Situations, IIS, IOA, social anxiety, assertiveness, social skills training, behavioral assessment, interpersonal distress, psychometrics, social phobia, avoidance behavior

Authors

The Inventory of Interpersonal Situations was developed and psychometrically refined by two prominent Dutch clinical psychologists and researchers:

• C. M. J. (Rien) Van Dam-Baggen, Ph.D.: Department of Clinical Psychology, University of Amsterdam (Universiteit van Amsterdam), Amsterdam, The Netherlands. Corresponding email for psychometric archival queries: [email protected].
• Floris W. Kraaimaat, Ph.D.: Department of Medical Psychology, Radboud University Medical Center (Radboudumc), Nijmegen, and Utrecht University, The Netherlands.

Purpose

The primary purpose of the Inventory of Interpersonal Situations (IIS) is to provide a comprehensive, multidimensional, and situation-specific assessment of social functioning, interpersonal difficulty, and subjective distress. Unlike traditional unidimensional social anxiety measures that solely capture cognitive apprehension or physiological hyperarousal, the IIS explicitly disentangles emotional reactivity from overt behavioral performance.

In clinical practice, individuals presenting with social difficulties exhibit marked heterogeneity. For example, some individuals experience profound subjective discomfort when engaging in social interactions yet exhibit normative behavioral frequencies due to strict vocational or personal obligations (high discomfort, high frequency). Conversely, others avoid social situations entirely to escape distress, thereby exhibiting moderate self-reported situational discomfort simply because their experiential exposure is near zero (moderate/low discomfort due to avoidance, low frequency). Traditional instruments that conflate discomfort with frequency frequently misclassify or obscure these discrete behavioral phenotypes. The IIS overcomes this fundamental diagnostic limitation by presenting identical situational stimuli across both axes, facilitating precise functional behavioral analyses.

The IIS is widely deployed across diverse settings:

• Diagnostic Clarification: Differentiating generalized social anxiety disorder from circumscribed social phobias, avoidant personality structures, and mood-related social withdrawal.
• Treatment Planning and Personalization: Identifying specific domains of interpersonal deficits (e.g., severe inhibition in positive assertion versus difficulties with negative assertion) to guide structured behavioral interventions, such as Cognitive-Behavioral Therapy (CBT) and Social Skills Training (SST).
• Outcome Evaluation: Measuring therapeutic change following clinical interventions. Because the scale captures both behavioral frequency and subjective discomfort, clinicians can determine whether an intervention has reduced subjective distress, increased assertive behavior, or successfully facilitated both.
• Empirical Research: Serving as a standardized psychometric benchmark in clinical trials, cross-cultural comparative research on social interaction norms, and experimental studies investigating social-evaluative threat.

Psychological Construct

The psychological construct evaluated by the IIS centers on interpersonal functioning within social-evaluative contexts. Specifically, the instrument operationalizes interpersonal functioning along two orthogonal primary axes across five distinct situational domains:

Primary Axes

• Interpersonal Discomfort (Anxiety / Affective Distress): Reflects the intensity of subjective anxiety, internal tension, physiological activation, and emotional distress elicited by a specific interpersonal encounter. It measures the degree to which an individual fears negative evaluation, rejection, or interpersonal conflict.
• Frequency of Social Behavior (Overt Behavioral Enactment): Represents the empirical frequency with which the respondent actually carries out the specific social behavior when encountered in daily life. This captures overt approach behavior versus behavioral avoidance or behavioral inhibition.

Factorially Derived Interpersonal Domains (Subscales)

1. Giving Criticism and Standing Up for One’s Rights: Evaluates situations involving negative assertion where the individual must address interpersonal grievances, rectify unfair treatment, or manage conflict. Examples include telling an acquaintance that their behavior is bothersome, returning defective merchandise, or addressing an offensive remark.
2. Expressing Personal Opinions: Measures the capacity and willingness to articulate divergent personal viewpoints, values, or philosophies within peer groups, unfamiliar assemblies, or authority contexts where peer pressure or social conformity operates.
3. Giving and Receiving Positive Regard (Positive Assertion): Evaluates an individual’s comfort and frequency in expressing genuine appreciation, delivering compliments, receiving accolades gracefully, and accepting warmth from others. Difficulties in this domain often indicate deep-seated feelings of unworthiness or fear of intimacy.
4. Initiating Social Contact: Pertains to initiating and maintaining spontaneous conversations with strangers, striking up dialogue with attractive individuals, asking unfamiliar peers to engage in shared activities, and entering ongoing group discussions.
5. Refusing Requests and Establishing Boundaries: Reflects the ability to say "no" to unsolicited offers, decline requests from authority figures or liked peers, turn down loans, and assertively defend one’s autonomy against manipulative compliance pressure.

Theoretical Framework

The Inventory of Interpersonal Situations is grounded in the convergence of behavioral psychology, social learning theory, and cognitive-behavioral models of social phobia. Historically, early behaviorists such as Joseph Wolpe and Andrew Salter framed assertive behavior as incompatible with reciprocal neurotic anxiety. In the 1970s and 1980s, behavioral theorists like Michael Argyle, Peter Trower, and Richard Eisler expanded this framework into comprehensive models of social competence, positing that interpersonal functioning depends both on behavioral repertoires (social skills) and conditioned affective reactions (social anxiety).

Furthermore, the IIS is deeply informed by Albert Bandura’s Social Cognitive Theory, which emphasizes the critical distinction between behavioral capability (competence) and outcome expectancies. Van Dam-Baggen and Kraaimaat hypothesized that socially anxious individuals do not necessarily suffer from an absolute deficit in social skills; rather, dysfunctional cognitive appraisals, anticipated negative evaluations (as elaborated in Clark and Wells’ cognitive model of social phobia), and conditioned fear responses actively suppress behavioral execution.

By measuring both subjective emotional distress (Discomfort) and behavioral execution (Frequency) across identical, ecologically valid situational vignettes, the IIS operationalizes this cognitive-behavioral paradigm. The situational specificity hypothesis—which posits that social anxiety is not an undifferentiated global trait but rather varies systematically based on the nature of the interpersonal demands (e.g., standing up to authority vs. initiating dating behaviors)—serves as the foundational structural premise of the instrument.

Validity

The psychometric validity of the IIS has been comprehensively demonstrated across clinical, student, and community samples throughout Europe and North America:

Construct and Convergent Validity

The IIS exhibits robust convergent validity with validated self-report measures of social anxiety, shyness, and assertiveness. The Discomfort dimension correlates strongly and positively with the Social Avoidance and Distress Scale (SAD) ($r = .68$ to $.76$) and the Fear of Negative Evaluation Scale (FNE) ($r = .62$ to $.71$). Conversely, the Frequency scale correlates positively with standardized assertiveness measures, such as the Rathus Assertiveness Schedule (RAS) ($r = .55$ to $.67$) and the Assertion Inventory by Gambrill and Richey, while demonstrating significant negative correlations with generalized measures of behavioral inhibition.

Discriminant and Criterion Validity

The IIS effectively discriminates clinical from non-clinical populations. In foundational validation studies by Van Dam-Baggen and Kraaimaat (1987, 1999, 2000), patients diagnosed with DSM-defined Social Phobia scored significantly higher on the Total Discomfort scale ($p < .001$, effect size Cohen’s $d > 1.5$) and significantly lower on the Total Frequency scale ($p < .001$, Cohen’s $d > 1.2$) compared to healthy matched controls and non-anxious psychiatric outpatient groups. Moreover, psychiatric inpatients presenting with personality disorders characterized by interpersonal withdrawal (e.g., Avoidant, Dependent) exhibited distinct subscale configurations relative to patients with mood or psychotic disorders.

Predictive and Ecological Validity

Studies linking IIS scores to in vivo behavioral performance demonstrate high predictive accuracy. Van Dam-Baggen and Kraaimaat (1990) showed that pre-treatment Discomfort scores significantly predicted heart-rate reactivity and speech duration during standardized behavioral role-play tests (BART). Additionally, the Frequency scale demonstrated strong sensitivity to therapeutic change, exhibiting marked, statistically significant increases following social skills training (SST) and cognitive therapy.

Reliability

The reliability of the IIS has been rigorously substantiated across multiple psychometric investigations:

• Internal Consistency: The internal consistency coefficients for the broad composite dimensions are consistently high. The Discomfort scale achieves a Cronbach’s alpha ranging from $\alpha = .92$ to $.96$ across clinical and community populations. The Frequency scale demonstrates internal consistency ranging from $\alpha = .88$ to $.93$. Across the five specific factor subscales, Cronbach’s alpha coefficients remain robust, consistently exceeding $.75$ and frequently reaching $.85$ to $.91$.
• Test-Retest Reliability: Temporal stability assessments conducted across 2-week, 4-week, and 6-week intervals with untreated student and clinical control samples reveal Pearson correlation coefficients exceeding $r = .82$ for Discomfort and $r = .80$ for Frequency, establishing that the scale reliably reflects stable individual differences while retaining sensitivity to genuine clinical intervention.
• Standard Error of Measurement: Standard error of measurement (SEM) indices derived from normative reference groups remain sufficiently small to permit confident tracking of individual patient trajectories using Reliable Change Index (RCI) metrics.

Factor Analysis

The dimensional structure of the IIS was established through extensive exploratory factor analyses (EFA) using principal axis factoring with both orthogonal (Varimax) and oblique (Oblimin) rotations, and subsequently cross-validated using confirmatory factor analysis (CFA) across diverse cultural cohorts (Van Dam-Baggen & Kraaimaat, 1991, 1999; Van Dam-Baggen et al., 2003).

Factor analyses conducted independently on the Discomfort data and Frequency data reveal an identical, coherent five-factor structure accounting for over 48% to 54% of the total variance:

• Factor 1: Giving Criticism / Negative Assertion: Highly saturated by items involving confrontation, addressing offensive behavior, returning defective products, and expressing frustration with disruptive conduct (e.g., Items 2, 6, 7, 10, 18, 21, 31, 33).
• Factor 2: Expressing Opinions: Items representing public ideological or evaluative discourse, particularly when opinions diverge from peers or authority figures (e.g., Items 14, 16, 20, 30, 34).
• Factor 3: Positive Assertion: Items capturing the delivery and acceptance of compliments, gratitude, and expressions of mutual regard (e.g., Items 4, 9, 17, 23, 26, 27, 28).
• Factor 4: Initiating Contact / Strangers: Items requiring active behavioral initiation with novel social targets, groups, or attractive individuals (e.g., Items 1, 12, 13, 15, 19, 29, 35).
• Factor 5: Refusing Requests / Autonomy: Situations demanding resistance to external pressures from salespersons, superiors, or close peers (e.g., Items 3, 5, 8, 22, 25, 32).

Confirmatory factor analytic models testing this five-factor correlated structure against alternative unifactorial or two-factor models yield significantly superior model fit indices ($ ext{RMSEA} < .05$,$ ext{CFI} > .92$,$ ext{TLI} > .91$).

Instrument / Measurement Tool

• Test Type: Multi-item, self-administered clinical behavioral inventory.
• Administration Format: Paper-and-pencil questionnaire or interactive computerized assessment.
• Target Population: Adolescents and adults (ages 16 and older).
• Estimated Completion Time: 15 to 25 minutes.
• Item Composition: 35 distinct social scenario statements, each evaluated independently along two response scales.
• Response Dimensions and Scaling:
  • Part 1: Discomfort (Social Anxiety / Distress): Rated on a 5-point Likert scale:
    • 1 = None
    • 2 = A little
    • 3 = A fair amount
    • 4 = Much
    • 5 = Very much
  • Part 2: Frequency of Occurrence (Behavioral Execution): Rated on a 5-point Likert scale:
    • 1 = Never
    • 2 = Seldom
    • 3 = Sometimes
    • 4 = Often
    • 5 = Always
• Scoring Methodology:
  • Total Scores: Summing item ratings yields a Total Discomfort score (range: 35–175) and a Total Frequency score (range: 35–175).
  • Subscale Scores: Subscale totals are generated by summing item scores belonging to each respective factor.
  • Profile Interpretation: Comparing standardized percentile or decile scores across Discomfort and Frequency enables identification of distinct behavioral subtypes (e.g., High Discomfort/Low Frequency = Avoidant/Inhibited; High Discomfort/High Frequency = Anxiously Assertive; Low Discomfort/High Frequency = Competent/Uninhibited).

Permissions & Fee and Test Year

The Inventory of Interpersonal Situations was first published in its standardized test manual form in 1987 under the Dutch title Handleiding bij de Inventarisatielijst Omgaan met Anderen (IOA) by Swets & Zeitlinger (later Pearson Assessment). The standardized English version was formally published in the peer-reviewed literature in 1999 in the European Journal of Psychological Assessment.

Licensing and Accessibility: The scale items and scoring algorithms were released into the public academic domain for non-commercial research and educational applications by the primary authors. Clinical use, commercial reproduction, or large-scale digital distribution may require adherence to publishing rights previously managed through academic test publishers (Swets & Zeitlinger / Hogrefe / Pearson). Researchers and clinicians seeking formal testing manuals, norm tables, or author inquiries should contact Dr. C. M. J. Van Dam-Baggen ([email protected]) or consult published academic archives.

References

• Van Dam-Baggen, C. M. J., & Kraaimaat, F. W. (1987). Handleiding bij de Inventarisatielijst Omgaan met Anderen, de IOA [Manual of the Inventory of Interpersonal Situations: IIS]. Lisse: Swets & Zeitlinger.
• Van Dam-Baggen, R., & Kraaimaat, F. (1987). Aspects of social anxiety and situational specificity in psychiatric patients. In J. P. Dauwalder, M. Perrez, & V. Hobi (Eds.), Controversial issues in behavior modification: Annual series of European research in behavior therapy (Vol. 2). Amsterdam/Lisse: Swets & Zeitlinger.
• Van Dam-Baggen, R., & Kraaimaat, F. (1989). Social anxiety: A review. In P. M. G. Emmelkamp, W. T. A. M. Everaerd, F. W. Kraaimaat, & M. J. M. van Son (Eds.), Fresh perspectives on anxiety disorders (Annual Series of European Research in Behavior Therapy, Vol. 4). Amsterdam/Lisse: Swets & Zeitlinger.
• Van Dam-Baggen, C. M. J., & Kraaimaat, F. W. (1990). Zelfbeoordeling van sociale angst als predictor van observeerbaar gedrag in sociale situaties [Self-report of social anxiety as predictor of overt behavior in social situations]. Nederlands Tijdschrift voor de Psychologie, 45, 180–183.
• Van Dam-Baggen, C. M. J., & Kraaimaat, F. W. (1990). Inventarisatielijst Omgaan met Anderen, IOA. Herziene Handleiding deel 2 [Inventory of Interpersonal Situations. IIS. Revised Manual, Vol. 2]. Lisse: Swets & Zeitlinger.
• Van Dam-Baggen, R., Kraaimaat, F., & Kiers, H. (1991). De Inventarisatielijst Omgaan met Anderen (IOA): Een vervolgonderzoek naar de validiteit van de subschalen [The Inventory of Interpersonal Situations (IIS): A follow-up study on the validity of the subscales]. Gedragstherapie, 24, 89–98.
• Van Dam-Baggen, C. M. J., Kraaimaat, F. W., & Kiers, H. A. L. (1992). Een exploratief onderzoek naar de structuur van sociale angst bij sociaal angstige psychiatrische patienten [An exploratory study of the structure of social anxiety in socially anxious psychiatric patients]. Nederlands Tijdschrift voor de Psychologie, 47, 41–45.
• Van Dam-Baggen, R., Kraaimaat, F., & Crouzen, M. (1993). De effectiviteit van sociaalvaardigheidstherapie bij drie subtypen sociaal angstige psychiatrische patiënten [The effectiveness of social skills training in three subtypes of socially anxious psychiatric patients]. Gedragstherapie, 26, 21–32.
• Van Dam-Baggen, R., & Kraaimaat, F. (1999). Assessing social anxiety: The Inventory of Interpersonal Situations (IIS). European Journal of Psychological Assessment, 15(1), 25–38. https://doi.org/10.1027/1015-5759.15.1.25
• Van Dam-Baggen, C. M. J., & Kraaimaat, F. W. (2000). Group social skills training or cognitive group therapy as the clinical treatment of choice for generalized social phobia? Journal of Anxiety Disorders, 14(5), 437–451. https://doi.org/10.1016/S0887-6185(00)00032-8
• Van Dam-Baggen, C. M. J., & Kraaimaat, F. W. (2003). Social anxiety in three Western societies. Journal of Clinical Psychology, 59(6), 673–686. https://doi.org/10.1002/jclp.10091

13. Items of the Scale (Questionnaire)