revised Sociosexual Orientation Inventory (SOI-R)

Abstract

The revised Sociosexual Orientation Inventory (SOI-R) is a psychological instrument developed by Lars Penke and Jens B. Asendorpf (2008) to measure individual differences in the personality construct of sociosexuality. Sociosexuality describes the willingness or tendency to engage in sexual relationships without requiring deep emotional intimacy or long-term commitment. Developed as a successor to the original Sociosexual Orientation Inventory (SOI) by Simpson and Gangestad (1991), the SOI-R addresses several critical psychometric shortcomings of its predecessor. Crucially, the SOI-R offers a multidimensional assessment, allowing researchers to measure three distinct facets of sociosexuality: behavior, attitude, and desire. This differentiated approach has proven highly valuable in personality psychology, sexuality research, and evolutionary psychology, as these facets often exhibit unique relationships with other variables.

Keywords

Sociosexual Orientation Inventory, SOI-R, Sociosexuality, Sexual Behavior, Sexual Attitudes, Sexual Desire, Restricted Sociosexuality, Unrestricted Sociosexuality, Evolutionary psychology, Mating Strategies, Psychometrics.

Authors

Lars Penke, Jens B. Asendorpf

Purpose

The primary purpose of the SOI-R is to provide a reliable, valid, and economic measurement instrument for assessing individual differences in sociosexual orientation. The scale was specifically created to refine and replace the original SOI by offering a more precise, multidimensional structure.

The SOI-R allows researchers to move beyond a global score of sociosexuality and investigate the independent contributions of sexual behavior, attitudes toward casual sex, and sexual desire relating to non-committed partners. The authors emphasize that sociosexuality should be treated as a continuous, dimensional construct, measured along a spectrum rather than categorized using an arbitrary cut-off point separating “restricted” versus “unrestricted” orientations. This dimensional approach is essential for accurate statistical analysis and interpretation in academic settings.

Construct

The psychological construct measured by the SOI-R is Sociosexual Orientation (or Sociosexuality). This construct reflects the extent to which an individual prefers sexual relationships that are unconstrained by emotional commitment or long-term relationship goals. High scores reflect an “unrestricted” orientation, characterized by a greater openness to casual sex, while low scores reflect a “restricted” orientation, characterized by a preference for sexual activity only within the context of a committed relationship.

The SOI-R operationalizes this construct through three empirically distinct, yet theoretically related, sub-facets:

• Behavior: Measures actual past sexual activity outside of committed relationships, including the number of partners and frequency of one-night stands.
• Attitude: Measures an individual’s cognitive and evaluative comfort level concerning casual, non-committed sex (e.g., belief that “sex without love is OK”).
• Desire: Measures motivational aspects, specifically the frequency of sexual fantasies and spontaneous arousal regarding individuals with whom the respondent is not in a committed romantic relationship.

Validity

The development of the SOI-R was fundamentally driven by the need to enhance the structural and construct validity of sociosexuality measurement. Empirical studies using the SOI-R consistently demonstrate that the three facets—Behavior, Attitude, and Desire—show differential associations with various external psychological and biological variables, supporting the scale’s divergent validity and confirming that the global score alone obscures important variance.

The differentiation of the construct is considered highly advisable because the distinct relationships observed between the three facets and other variables provide stronger evidence of construct validity than the single-factor model of the original SOI. The instrument’s ability to predict differential patterns in courtship and relationship dynamics further establishes its predictive validity.

Reliability

The SOI-R was designed to correct recognized psychometric deficiencies present in the original SOI, resulting in improved internal consistency and test-retest reliability across its subscales. The nine-item structure ensures that each of the three facets is measured by three dedicated items, stabilizing the subscale scores and increasing the reliability of the overall measurement of sociosexual orientation. Detailed manual information, including item keys and norms, is generally provided by the authors to ensure consistent and reliable application in research settings.

Factor Analysis

Factor analysis of the SOI-R has consistently supported a three-factor structure, confirming the theoretical distinction between Behavior, Attitude, and Desire. This structure is a key improvement over the original SOI, which was often treated as having a single factor despite empirical challenges. The SOI-R items are specifically grouped as follows:

• Behavior Items: Items 1, 2, and 3.
• Attitude Items: Items 4, 5, and 6.
• Desire Items: Items 7, 8, and 9.

The confirmed three-factor model allows for the separate analysis of these components, demonstrating that sociosexuality is a complex, multidimensional construct that requires nuanced measurement.

Instrument

Test Type: Self-report psychological inventory

Format: Nine items, divided into three subscales (Behavior, Attitude, Desire). Items use a combination of frequency counting (Behavior) and 5-point Likert scales (Attitude and Desire).

Language Available: The SOI-R has been translated and validated in over 25 different languages. Information regarding these translations is available online: 25 different languages (click here).

Population Group: General adult population.

Age Group: Typically utilized with adults (18 years and older).

Population Details: The scale is widely used in college student and community samples globally, particularly in studies related to human mating strategies and personality psychology.

Test Methodology: Respondents provide self-report data. The scoring involves aggregating the responses, often requiring specific transformations for the non-Likert behavior items, yielding three subscale scores and a total SOI-R score. Scoring is continuous, reflecting the dimensional construct nature of sociosexuality.

Keywords

Sexual Orientation, Mating Effort, Casual Sex, Personality Inventory, Multidimensional Scale, Human Sexuality, Psychological Measurement, Relationship Science.

Authors

Author ORCID Identifier: Information not provided in source content.

Affiliation Email addresses: Information not provided in source content.

Correspondence Address: Information not provided in source content.

Permissions & Fee and Test Year

The SOI-R is widely used in academic research, and the authors explicitly grant permission for researchers to utilize the official English items in their studies. There is generally no formal fee required for academic use, provided the scale and its authors are properly cited using the primary 2008 reference.

Test Year: 2008 (Year of publication for the revised instrument).

Reference’s

The definitive reference for the revised Sociosexual Orientation Inventory (SOI-R) is:

• Penke, L., & Asendorpf, J. B. (2008). Beyond global sociosexual orientations: A more differentiated look at sociosexuality and its effects on courtship and romantic relationships. Journal of Personality and Social Psychology, 95, 1113-1135.

Items of the revised Sociosexual Orientation Inventory (SOI-R)

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

Please respond honestly to the following questions:

With how many different partners have you had sex within the past 12 months?

With how many different partners have you had sexual intercourse on one and only one occasion?

With how many different partners have you had sexual intercourse without having an interest in a long-term committed relationship with this person?

Sex without love is OK.

I can imagine myself being comfortable and enjoying “casual” sex with different partners.

I do not want to have sex with a person until I am sure that we will have a long-term, serious relationship.

How often do you have fantasies about having sex with someone you are not in a committed romantic relationship with?

How often do you experience sexual arousal when you are in contact with someone you are not in a committed romantic relationship with?

In everyday life, how often do you have spontaneous fantasies about having sex with someone you have just met?