Revised Sociosexual Orientation Inventory

Abstract

The Revised Sociosexual Orientation Inventory (SOI-R) is a nine-item, self-report questionnaire developed by Penke and Asendorpf (2008) to address conceptual and psychometric limitations of the original Sociosexual Orientation Inventory (SOI; Simpson & Gangestad, 1991). The construct of sociosexuality captures individual differences in the propensity for engaging in casual, uncommitted sexual relationships. Unlike the unidimensional SOI, the SOI-R assesses sociosexuality through a three-factor model, providing a more differentiated understanding of this psychological variable. The three distinct facets measured are Behavior (past casual sexual encounters), Attitude (explicit acceptance of uncommitted sex), and Desire (sexual interest in people outside of a committed romantic context). The SOI-R utilizes Likert-type rating scales and has demonstrated strong internal consistency and predictive validity comparable to the original SOI, while offering greater discriminant validity among its facets, which show distinct patterns of correlation with various behavioral outcomes and personality traits.

Keywords

Sociosexuality, Sociosexual Orientation Inventory, SOI-R, casual sex, sexual behavior, Attitude, Desire, psychometrics, personality, self-report questionnaire

Authors

Lars Penke, Jens B. Asendorpf

Purpose

The primary purpose of the SOI-R is to provide a comprehensive and psychometrically robust measure of sociosexuality that overcomes the limitations inherent in the original, unidimensional Sociosexual Orientation Inventory (SOI). The SOI-R was specifically designed to resolve issues such as low internal consistency, multifactorial structure confusion, skewed score distributions, and the inappropriateness of certain items for single individuals that plagued the original instrument.

By differentiating the construct into three distinct facets—Behavior, Attitude, and Desire—the SOI-R allows researchers to analyze the unique components underlying individual differences in the tendency toward uncommitted sex. This differentiation enables more nuanced research into the dynamics of courtship, romantic relationships, and related psychological constructs, making it a suitable tool for fields ranging from social and personality psychology to evolutionary psychology and gender studies.

Construct

The SOI-R measures sociosexual orientation, which is defined as individual differences in the readiness to engage in sexual relationships without emotional closeness or long-term commitment. This concept, originally introduced by Alfred Kinsey, varies along a continuum from “restricted” (preferring sex exclusively within emotionally close, committed relationships) to “unrestricted” (willingness to have sexual relationships with low commitment, often with changing partners or after short acquaintances).

The SOI-R operationalizes this orientation across three relatively independent facets:

• Behavior: This facet measures past sociosexual behavior, specifically the number of casual and changing sexual partners (e.g., number of partners in the last 12 months and lifetime number of “one-night stands”).
• Attitude: This facet assesses the explicit cognitive and emotional acceptance of uncommitted sex, including comfort with casual sex and acceptance of sex without love.
• Desire: This facet, which was poorly represented in the original SOI, measures the frequency of spontaneous sexual fantasies and sexual arousal directed toward people with whom the individual is not in a committed romantic relationship.

The three facets show low to moderate positive intercorrelations (ranging from .17 to .55), supporting the utility of treating them as distinct yet related components of global sociosexuality.

Validity

The SOI-R exhibits strong evidence for both convergent and discriminant validity, as demonstrated in large-scale studies by Penke and Asendorpf (2008). Convergent validity is established by showing that the SOI-R full-scale score correlates similarly to the original SOI with established correlates of sociosexuality. These correlates include sex differences, infidelity, mate choice preferences, sex drive, personality traits (such as shyness and sensation seeking), and flirting behavior.

Crucially, the SOI-R demonstrates superior discriminant validity through its facet structure, revealing highly distinctive patterns of relationships for Behavior, Attitude, and Desire:

• Desire showed the most pronounced sex differences and uniquely predicted past sexual behaviors, observer-rated attractiveness, self-perceived mate value, and female flirting behavior.
• Attitude was primarily responsible for effects on mate preferences, assortative mating, and a partner’s flirtatiousness outside the relationship.
• Behavior and Desire, but not Attitude, were predictive of the number of sexual partners and changes in romantic relationship status over a 12-month period.

These differentiated findings confirm that the SOI-R facets reflect unique components of sociosexuality, underscoring the necessity of studying them separately to fully understand the construct’s underlying dynamics.

Reliability

The SOI-R demonstrates good internal consistency for both its facet scores and the total score across both the 5-point and 9-point response formats (see Table 1 in the original source content for detailed statistics). Cronbach’s alpha values generally indicate strong reliability.

Furthermore, the SOI-R shows good 1-year retest stability for the total score and the Behavior and Attitude facets, particularly when the 9-point scale is employed. The Desire facet, however, exhibited lower retest stability. This reduced stability is theorized to be related to transactional effects with romantic relationship status; for instance, women often report more restrictive desires when initiating a new relationship and less restrictive desires when separating, suggesting that the Desire facet is highly responsive to changes in relationship dynamics (Penke & Asendorpf, 2008).

Factor Analysis

The development of the SOI-R involved extensive psychometric work, starting with the selection of items from an initial pool of 47 using exploratory factor analysis and item analysis (Penke, 2006). Subsequent confirmatory factor analysis provided strong support for the three-factor structure proposed by Penke and Asendorpf (2008).

The analysis confirmed that the nine items reliably represent three distinctive facets of sociosexuality: Behavior, Attitude, and Desire. While these facets are positively intercorrelated (ranging from .17 to .55), they are sufficiently distinct to warrant separate measurement. Importantly, the factorial structure of the SOI-R was found to be invariant between the sexes, confirming that the scale is equally appropriate for both men and women, although the correlation between the Attitude and Behavior facets was significantly larger for women than for men.

Instrument

Test Type: Self-report questionnaire / Psychological scale

Format: Nine items answered on Likert-type rating scales.

Language Available: The SOI-R is available in numerous translations, including Chinese, Dutch, English, French, German, Icelandic, Italian, Malaysian, Spanish, and Swedish. These items are available for download online.

Population Group: General population (including hetero-, bi-, and homosexual individuals, and those of any relationship/marital status).

Age Group: Appropriate for individuals aged 18 to 60 years.

Population Details: Suitable for individuals of any normal-range educational level. Note: Some facets may not function optimally for sexually inexperienced or asexual individuals.

Test Methodology: The SOI-R uses two alternative response scale formats: a 5-point scale and a 9-point scale, both showing comparable psychometric properties. The 5-point scale is generally recommended for ease of discrimination by most subjects (especially nonstudents). Completion time is short, typically 1 to 2 minutes.

Keywords

Sociosexuality, SOI-R, Penke & Asendorpf, sexual Attitude, sexual Desire, sexual Behavior, psychometrics, evolutionary psychology, sex differences, internal consistency

Authors

Author ORCID Identifier: Not provided in source content.

Affiliation Email addresses: [email protected]

Correspondence Address: Lars Penke, Centre for Cognitive Ageing and Cognitive Epidemiology, Department of Psychology, University of Edinburgh, 7 George Square, Edinburgh, EH8 9JZ, UK.

Permissions & Fee and Test Year

Permissions & Fee: The SOI-R can be freely used for research purposes.

Test Year: Developed and published in 2008 (Penke & Asendorpf, 2008).

The SOI-R items and data are partly available online at the author’s official website: www.larspenke.eu/soi-r/. The original manuscript detailing the development is Penke (2006). The original PDF can be downloaded here: Penke, L. (2006). Development of the revised Sociosexual Orientation Inventory (SOI-R). Unpublished manuscript, Institute of Psychology, Humboldt University of Berlin.

Reference’s

• Asendorpf, J. B., & Penke, L. (2005). A mature evolutionary psychology demands careful conclusions about sex differences. Behavioral and Brain Sciences, 28, 275–276.

• Kinsey, A., Pomeroy, W., & Martin, C. (1948). Sexual behavior in the human male. Philadelphia: Saunders.

• Kinsey, A., Pomeroy, W., Martin, C., & Gebhard, P. (1953). Sexual behavior in the human female. Philadelphia: Saunders.

• Penke, L. (2006). Development of the revised Sociosexual Orientation Inventory (SOI-R). Unpublished manuscript, Institute of Psychology, Humboldt University of Berlin.

• 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.

• Schmitt, D. P. (2005). Sociosexuality from Argentina to Zimbabwe: A 48-nation study of sex, culture, and strategies of human mating. Behavioral and Brain Sciences, 28, 247–275.

• Simpson, J. A., & Gangestad, S. W. (1991). Individual differences in sociosexuality: Evidence for convergent and discriminant validity. Journal of Personality and Social Psychology, 60, 870–883.

• Simpson, J. A., Wilson, C. L., & Winterheld, H. A. (2004). Sociosexuality and romantic relationships. In J. H. Harvey, A. Wenzel, & S. Sprecher (Eds.), Handbook of sexuality in close relationships (pp. 87–111). Mahwah, NJ: Erlbaum.

• Townsend, J. M., Kline, J., & Wasserman, T. H. (1995). Low-investment copulation: Sex differences in motivations and emotional reactions. Ethology and Sociobiology, 16, 25–51.

• Voracek, M. (2005). Shortcomings of the Sociosexual Orientation Inventory: Can psychometrics inform evolutionary psychology? Behavioral and Brain Sciences, 28, 296–297.

• Webster, G. D., & Bryan, A. (2007). Sociosexual attitudes and behaviors: Why two factors are better than one. Journal of Research in Personality, 41, 917–922.

Items of the Revised Sociosexual Orientation Inventory

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

Please respond honestly to all of the following questions. Your responses will be treated confidentially and anonymously.

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

   □ 0		□ 1		□ 2 to 3		□ 4 to 7		□ 8 or More
   □	□	□	□	□	□	□	□	□
   0	1	2	3	4	5–6	7–9	10–19	20 or More

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

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

   4. Sex without love is OK. c‌
   1 □ Totally Disagree	2 □		3 □		4 □			5 □ Totally Agree
   1 □ 2 □ Strongly Disagree	3 □	4 □	5 □	6 □		7 □	8 □	9 □ Strongly Agree

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

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

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

      1 □ Never	2 □ Very Seldom		3 □ About Once a Month		4 □ About Once a Week		5 □ Nearly Every Day
      1 □	2 □	3 □	4 □	5 □	6 □	7 □	8 □	9 □
      Never	Very	About Once	About	About Once	About	Several	Nearly	At Least
      	Seldom	Every Two	Once a	Every Two	Once a	Times per	Every Day	Once a
      		or Three Months	Month	Weeks	Week	Week		Day

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

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