1. Infidelity in Heterosexual Couples: Demographic, Interpersonal, and Personality-Related Predictors of Extradyadic Sex Kristen P. Mark, M.Sc., 1 Erick Janssen, Ph.D., 2 & Robin R. Milhausen, Ph.D. 3 1 Department of Applied Health Science, Indiana University; 2 The Kinsey Institute for Research in Sex, Gender, & Reproduction, Indiana University; 3 Department of Family Relations and Applied Nutrition, University of Guelph  Similar amounts of variance were accounted for by variables in the men’s and women’s models.  Relationship variables such as happiness in relationship and perceived sexual compatibility were strong predictors of infidelity in women.  Personality variables, specifically sexual inhibition with regard to threat of performance consequences and threat of performance failure, performed similarly in the men’s and women’s regression models.  Men and women higher in inhibition due to threat of performance failure (SIS1) were more likely to report having engaged in infidelity in their current relationship.  Men and women higher in inhibition due to performance consequences (SIS2) were less likely to report having engaged in infidelity in their current relationship.  Men and women were more likely to report engaging in infidelity if they indicated their moods led them to engage in behavior they later regretted.  Demographic predictors including age, marital status, and the importance of religion, were not significant in either the men’s or the women’s models.  The findings suggest that (for both men and women) sexuality-related personality characteristics and (for women) relationship factors are more relevant to the prediction of sexual infidelity than demographic variables.  Approximately 20-25% of men and 10-15% of women report engaging in extramarital sex during their marriage (Laumann et al., 1994; Wiederman, 1997); this gender gap appears to be narrowing.  In a comparison of 160 cultures, Betzig (1989) found that infidelity was the most frequently cited cause of divorce.  The vast majority of men and women believe that it is “always” or “almost always” wrong for a committed person to have sex with someone other than their partner (Smith, 1994).  Previous predictors and correlates of infidelity include:  Demographic: Age, gender, race, religiosity, level of education, etc.  Interpersonal: Relationship dynamics, peer groups, etc.  Individual: Personality factors, values, opportunity, etc.  The role of sexual traits (e.g., sexual excitation and inhibition; Bancroft & Janssen, 2000) in infidelity – which can be conceived of as a form of risk-taking – has as yet not been investigated. BACKGROUND PURPOSE The purpose of the current study was to assess the relative importance of demographic, interpersonal, and sexual trait factors in predicting infidelity in heterosexual couples. SUMMARY & CONCLUSIONS RESULTS PARTICIPANTS  Convenience sample of 918 heterosexual men (N =506, M age = 28) and women (N = 412, M age = 33), who indicated being in a monogamous relationship and who completed a series of questionnaires on The Kinsey Institute's website.  The majority identified as Caucasian (88.5%), married (45%), and regarded religion as slightly or not important (65%).  In total 22% of men and women indicated they had engaged in infidelity in their current relationship; there were no significant gender differences in likelihood of engaging in infidelity. Results of Logistic Regression Analyses Using Demographic, Interpersonal, and Personality Factors to Predict Infidelity among Men Results of Logistic Regression Analyses Using Demographic, Interpersonal, and Personality Factors to Predict Infidelity among Women The Kinsey Institute for Research in Sex, Gender, and Reproduction BWaldExp(B) Age -.032.80.97 Marital Status -.29.66.75 Importance of Religion.462.131.59 Relationship Satisfaction.967.52**2.62 Sexual Satisfaction -.511.80.60 Compatibility: Frequency of Sex -.26.42.77 Compatibility: Importance of Sex -.09.05.92 Compatibility: Sexual Values 1.078.54**2.93 SES.01.531.01 SIS1.077.69**1.08 SIS2 -.1413.46***.87 MSQ Regret.364.26*1.43 *** p<.001 **p<.01 * p<.05 (R 2 =.21)  Bivariate analyses (chi squares and t-tests) were conducted to assess the relationship between infidelity and demographic, interpersonal, and personality variables.  Logistic regression analyses were conducted using variables that were significant at the bivariate level and those of theoretical relevance: Age, marital status, importance of religion, relationship satisfaction, sexual satisfaction, compatibility in terms of a) frequency of sex, b) importance of sex, and c) sexual values, SES, SIS1, SIS2, and MSQ Regret.  The outcome variable was self-reported infidelity. ANALYSES “In your current relationship, have you ever cheated (i.e.: engaged in sexual interactions with someone other than your primary partner that could jeopardize, or hurt, your relationship)?” INFIDELITY BWaldExp(B) Age.022.721.02 Marital Status.10.121.11 Importance of Religion.402.651.49 Relationship Satisfaction.402.171.50 Sexual Satisfaction.30.881.35 Compatibility: Frequency of Sex -.00.001.0 Compatibility: Importance of Sex.401.61.50 Compatibility: Sexual Values.07 1.08 SES.045.89*1.04 SIS1.067.70**1.06 SIS2 -.076.23*.93 MSQ Regret.436.23*1.53 *** p<.001 **p<.01 * p<.05 (R 2 =.17)  Demographic information (e.g.,: gender, religiosity)  Interpersonal variables (e.g.,: relationship satisfaction, sexual satisfaction)  Sexual excitation (SES), sexual inhibition due to performance consequences (SIS1), sexual inhibition due to fear of performance failure (SIS2), and the Mood and Sexuality Questionnaire Regret subscale (MSQ Regret) MEASURES