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. Author manuscript; available in PMC: 2015 Jun 22.
Published in final edited form as: Arch Sex Behav. 2012 Sep 13;42(2):213–223. doi: 10.1007/s10508-012-0004-x

Unwanted Sexual Experiences in Young Men: Evidence from a Survey of University Students in Chile

Jocelyn A Lehrer 1, Evelyn L Lehrer 2, Mary P Koss 3
PMCID: PMC4475681  NIHMSID: NIHMS409404  PMID: 22971801

Abstract

The public health problem of unwanted sexual experiences (USE) in male youths has received little attention. In this study, we examined prevalence of USE, risk factors, contexts, and barriers to disclosure with data from a quantitative survey of students enrolled in General Education courses at a public university in Chile. This study focused on the male sample (N = 466). Approximately 20.4% of participants reported some form of USE since age 14. Forced sex through physical coercion, forced sex through verbal coercion or while intoxicated, attempted forced sex, and less severe forms of USE were reported by 0.2%, 10.1%, 1.4%, and 8.7% of participants, respectively. USE before age 14 was reported by 9.4% of participants and was a significant predictor of USE since age 14 (AOR 6.38, 95% CI 3.22–12.65, p < .01). The perpetrator of USE since age 14 was most commonly identified as a date/partner or friend/acquaintance; other findings on contexts and barriers to disclosure were also generally consistent with previous results in the literature. In addition, we found substantial co-occurrence of USE since age 14 with two other forms of coercion: physical dating violence victimization and coerced condom non-use. The study findings indicate a need for further attention to these public health problems and have implications for the development of violence and HIV/STI prevention programs for adolescent boys and young adult men in Chile and elsewhere.

Keywords: sexual coercion, sexual victimization, sexual violence, sexual abuse

INTRODUCTION

The public health problem of unwanted sexual experiences (USE) in adolescent boys and young adult men is poorly understood and has received little attention around the world. Despite the pervasive minimization and denial of such coercion, studies (primarily of adult men) have found that it can have a range of negative effects on psychological and physical health and sexual function (Choudhary, Coben, & Bossarte, 2010; Elliott, Mok, & Briere, 2004; Romito & Grassi, 2007; Tewksbury, 2007). History of USE has also been linked to higher rates of unprotected sex and other sexual risk behaviors and greater odds of having been diagnosed with a sexually transmitted infection (de Visser, Smith, Rissel, Richters, & Grulich, 2003; Kalichman et al., 2001; Kalichman & Rompa, 1995).

Evidence on the prevalence of USE in adolescent boys and young adult men is limited. In a multinational study of students enrolled in 38 universities, past-year physical coercion to have sex was reported by 2.8% of male students who had been in a heterosexual relationship in the past year; the corresponding figure for verbal coercion was 22.0% (Hines, 2007). In a sample drawn from 12 U.S. colleges, 22.2% of male participants reported some form of USE over their lifetime, with 8.3% reporting severe USE (involving threats and/or force) (Tewksbury & Mustaine, 2001). In a survey of University of Costa Rica students, 12.8% of male students reported some form of USE before age 18 (Krugman, Mata, & Krugman, 1992). Approximately 10.5% of men reported at least one lifetime USE occurrence in a survey of university students in Italy (Romito & Grassi, 2007). Analyses based on study populations outside the educational sector in various countries have also reported variable prevalence estimates (Cáceres, 2005; Choudhary et al., 2010; Olsson et al., 2000). In Chile’s 2000 National Survey of Sexual Behavior, administered to a representative urban sample of adults, 1.9% of male participants responded affirmatively to the question “Have you ever been a victim of rape?” (Goldstein et al., 2000); other forms of USE were not assessed.

A critical literature review based on samples of North-American and European adult men noted several reasons for the wide range of prevalence estimates, including differences in populations studied, time frames considered, and USE definitions (Peterson, Voller, Polusny, & Murdoch, 2011). Self-reports of USE are also known to be sensitive to number and phrasing of items and the context within which questions are placed in the survey (Abbey, Parkhill, & Koss, 2005). These differences across studies also have implications for examination of other aspects of USE, including risk factors, contexts, and barriers to disclosure.

The literature on risk factors for USE in adolescence and young adulthood is overwhelmingly based on samples of women. Numerous studies have identified childhood sexual abuse (CSA) in girls as a strong predictor of subsequent USE (Bachar & Koss, 2001; Maniglio, 2009). Research on violence-related sequelae of CSA in boys has largely focused on associations with subsequent perpetration of violence against women (Loh & Gidycz, 2006), but recent studies have begun to examine links with revictimization.

The multinational study of USE in university students cited above found that men with a history of CSA had elevated adjusted odds of both physically- and verbally-coerced sexual victimization over the past year; for each additional type of CSA experienced (in an eight-item scale), the odds of these forms of USE were 1.48 and 1.28 times greater, respectively (Hines, 2007). A Canadian national study of adults, currently or previously in marital or cohabiting unions, found a positive association of CSA in boys with subsequent physical (AOR = 1.88) and psychological (AOR = 3.01) intimate partner victimization (Daigneault, Hébert, & McDuff, 2009). Based on the National Violence Against Women Survey–a representative U.S. data set on adult men and women–another study found that among men who reported CSA, the AORs for physical and sexual victimization in adulthood (by intimate partners or other perpetrators) were 2.5 and 5.5, respectively (Desai, Thompson, & Basile, 2002). Just as the sexual behaviors assessed in measures of USE in young men vary greatly across studies, the same is true for CSA (Hulme, 2004; Senn, Carey, & Vanable, 2008); in the studies cited above, CSA measures ranged from assessing only the most severe types of USE (Desai et al., 2002) to assessing “unwanted sexual touching, fondling, rape, or attempted rape” (Daigneault et al., 2009, p. 640).

Regarding other risk factors, some studies have suggested that witnessing domestic violence in childhood may increase vulnerability to subsequent USE (Lehrer, Lehrer, Lehrer, & Oyarzún, 2007; Vézina & Hébert, 2007) and poor family functioning and cohesion have been linked with heightened risk of sexual revictimization among those with a history of CSA (Classen, Gronsyaka, & Aggarwal, 2005). Mixed findings have been reported regarding the influence of socioeconomic status of the family of origin (Hines, 2007; Lehrer et al., 2007). With regard to living arrangements, college students who reside away from their parents have less supervision and family support and may, therefore, be more vulnerable (Lehrer et al., 2007). Other research has found associations between measures of consensual sexual activity (e.g., frequency of consensual sex, multiple partners) and exposure to potential sexual aggressors (Bachar & Koss, 2001; Rickert & Wiemann, 1998). Urbanicity may also affect such exposure but has received little attention to date (Lehrer et al., 2007).

A small number of studies have examined contexts of USE in men. Research based on a nationally representative sample of U.S. adult men found that the most common assailants were acquaintances, friends or partners–but strangers were involved in 19.5-39.4% of cases where the perpetrator was male, varying by the type of USE (Choudhary et al., 2010). A high level of concurrent substance use was found in a New Zealand community-based study of USE in men who have sex with men (MSM) (Gavey, Schmidt, Braun, Fenaughty, & Eremin, 2009). Same-sex perpetrators have been found to be involved in a substantial minority of cases of USE in men (Cáceres, 2005; Choudhary et al., 2010; Romito & Grassi, 2007).

Research with women has found that underreporting of USE in surveys is often related to failure to perceive the experience as coercive or to recall the experience in response to item phrasing, and conscious decision not to report for reasons including feelings of shame (Kendall-Tackett & Becker-Blease, 2004; Koss et al., 1994); similar factors influence non-disclosure to the police and health professionals. In men, additional barriers to disclosure include fear of being judged to be gay, and widespread conceptions of masculinity which dictate that men should be physically and mentally strong, self-reliant, and sexually assertive (Davies, 2002; Donnelly & Kenyon, 1996; Sable, Danis, Mauzi, & Gallagher, 2006).

Other research on barriers to disclosure has found that male rape myths–false and prejudicial attitudes and beliefs regarding sexual assault against men (e.g., that sexual victimization cannot happen to men)–operate most strongly in the case of female assailants (Struckman-Johnson & Struckman-Johnson, 1992). Adherence to such myths has been found even among professionals who provide services in response to USE. For example, a qualitative study of 30 sexual assault crisis providers in a Southeastern U.S. city found that male law enforcement officers often did not acknowledge that men could be victims; at the same time, many female crisis center workers held the view that women almost never commit sexual violence and that, given their strength and power, men are rarely victims (Donnelly & Kenyon, 1996).

The present study analyzed a sample of male university students in Chile. As of 2008, 54.0% of men ages 18-23 years in the country were attending an institution of higher education (World Bank, 2011). To date, no quantitative studies have examined USE in this population. The aims of this study were to examine: (1) prevalence of and risk factors for USE since age 14, and (2) contexts and reasons for non-disclosure of USE. In our multivariate analyses, we focused on USE before age 14 as a predictor of USE since age 14, adjusting for two other domains addressed in the survey: witnessing domestic violence in childhood and socioeconomic/ demographic variables.

In ancillary analyses, we examined associations of USE since age 14 with two other forms of coercion in the same time period: physical dating violence victimization (PDV) and being coerced to have sex without a condom in the context of a consensual sexual encounter. Studies with adolescent girls and young adult women in the U.S. and other countries have documented high prevalence of co-occurrence of USE and PDV (not necessarily within the same relationship) (Lehrer, Lehrer, & Zhao, 2010; Smith, White, & Holland, 2003; White, 2009); related analyses have found a high prevalence of co-occurrence of PDV and coerced condom non-use (Lehrer et al., 2010) as well as a positive association between history of PDV and fear of negotiating condom use (Wingood et al., 2001). A study of students at 19 U.S. colleges found that substantial percentages of male and female participants reported co-occurrence of past-year sexual, physical, and psychological victimization by a dating partner (Sabina & Straus, 2008). To our knowledge, ours is the first study to assess co-victimization involving coerced condom non-use in adolescent boys and young adult men.

METHOD

Participants

The 2005 Survey of Student Well-Being, a closed-ended, self-administered questionnaire compiled by the lead author of this study, was administered to students attending General Education courses at a large, public university in Santiago with a socioeconomically diverse student body. Total enrollment in the 24 General Education classes was 2,451, with some students (the number is unknown) registered for more than one class. On the day of survey administration, 1,193 students were present in the 24 classes, consistent with the typical attendance rate; 970 students returned completed surveys, a response rate of 81%. Students who had completed the survey in another class were instructed not to do so again, which accounts for some of the non-response. Sixteen cases with missing data on participant’s sex were eliminated, along with four cases with invalid data: two students who reported that they had not provided honest responses and two students whose internally inconsistent responses indicated that they had not taken the survey seriously. The final sample included 484 women and 466 men. The present study utilized the male sample.

Procedure

The project was approved by the university’s Ethics Committee for Research on Human Subjects. Trained survey administrators explained the survey purpose and sensitive nature of the content to students, emphasizing that participation was voluntary and responses would be anonymous. Students signed and returned a consent form. They were instructed to sit one chair apart where possible and told that the first 25 minutes of the class period would be allocated to survey completion.

The survey items measured USE before and since age 14, PDV, coerced condom non-use, and family background variables, including childhood witnessing of domestic violence; most were based on scales validated in the U.S. After translation into Spanish, back-translation to English was performed to ensure accuracy; Chilean faculty and students also provided input to ensure that the translation preserved the intended meaning of the measures.

Measures

USE since age 14

The section in the questionnaire on USE began with a paragraph that established a context for recalling a range of such experiences, including incidents in which the participant may have been “asleep, drunk, or otherwise incapacitated,” and where “sex” was defined as vaginal, oral or anal sex. Participants were then asked to respond “yes” or “no” to the following items regarding USE since age 14: (1) Someone tried to make me have sex by using threats, arguments or physical force, but this did not happen; (2) Someone forced me to have sex using physical force; (3) Someone forced me to have sex using threats or other verbal pressures; (4) Someone had sex with me after I had been drinking or using drugs, and I was not in a condition to be able to stop what was happening; (5) Aside from the types of sexual contact already mentioned, have you experienced any unwanted sexual experiences, such as forced kissing or grabbing?

Items 2 and 3 above were adapted from the Conflict Tactics Scale–2 (Straus, Hamby, & Warren, 2003). Items 1 and 4 were included following the Sexual Experiences Survey (Koss et al., 2007); the wording was adapted for consistency with Items 2 and 3.

An affirmative response to Item 2, the most physically severe form of USE, was coded as physically-forced sex. Affirmative responses to Items 3 and 4 were coded, respectively, as verbally-forced sex and forced sex while intoxicated; an affirmative response to Item 1 was coded as attempted forced sex through physical or verbal coercion (henceforth, “attempts”). For use in the multivariate analyses, we constructed a summary dependent variable indicating the most severe form of USE since age 14, if any, reported by the participant. The three mutually exclusive categories were: (1) forced sex/ attempts; (2) less severe forms of USE (e.g., forced kisses, grabbing); and (3) no USE. Our definition of the most severe form of USE since age 14 must be distinguished from the participants’ own assessment of the most severe incident since age 14, discussed below in the section on contexts and disclosure.

USE before age 14

The main independent variable was operationalized as equal to 1 if the participant responded affirmatively to at least one of the following items: “Before age 14, did someone ever make you have sex against your will?” and “Before age 14, did you ever have any other form of unwanted sexual experience, such as forced kisses, grabbing, etc.?” Related to this measure, the survey also contained an item on the relationship of the perpetrator to the participant in the incident before age 14 considered most severe by the participant.

Control variables

We used three dummy variables to indicate frequency of childhood witnessing of violence between parents/guardians: “often,” “several times” and “rarely” (the reference category was “never”). A continuous variable measuring the participant’s age at the time of survey administration was used to adjust for length of exposure to USE risk. Parental education was coded as 1 if the highest educational level attained by the participant’s parents (or other adults who raised him) was 12 years of regular schooling or less or incomplete advanced technical schooling or less; we refer to this category as “low parental education.” An urbanicity variable was used to indicate that the participant lived in Santiago or another large city at age 14, and a non-intact family of origin variable to indicate that he did not live with both parents (biological or adoptive) at age 14. Other variables indicated whether the participant had primarily lived outside the parental home since entering college, and whether he had ever had consensual vaginal or anal sex.

Contexts of violence and disclosure

For participants who reported any USE since age 14, the survey included items regarding contexts of the incident considered most severe by the participant; these items addressed concurrent substance use, incident location, and perpetrator-participant relationship. Information was also collected on whether the participant told anyone about the incident and on barriers to reporting to the police.

Sex of perpetrators

Participants who reported any lifetime USE (before and/or since age 14) were asked a question on the sex of the perpetrators.

Co-victimization

The first measure used in co-victimization analyses was a variable for PDV, based on items adapted from a scale used by Foshee (1996). These items were addressed to participants who indicated that they had ever gone out on a date or had a romantic relationship since age 14. Prior to these items, the survey instrument included instructions that created a context for recalling incidents of unwanted physical violence. The PDV variable was coded as 1 if the participant reported that a date/partner had ever: “scratched or slapped me,” “pushed, grabbed, or shoved me,” “slammed me or held me against the wall,” “kicked or bit me,” “hit me with a fist,” “hit me with something hard,” “hit me repeatedly,” “tried to choke me,” “burned me,” and/or “assaulted me with a knife or gun.”

The second measure used in co-victimization analyses, adapted from an item in a scale developed by Straus et al. (2003), equals 1 if the participant responded affirmatively to the question: “Since age 14, has it ever happened that your boyfriend/girlfriend or dating partner made you have sex without a condom, when you wanted to use a condom?”

Data Analysis

After deleting 50 cases with missing data on USE before and/or since age 14, the study sample consisted of 416 men. We generated descriptive statistics for the dependent and independent variables, as well as a frequency distribution for the perpetrator-participant relationship in the incident before age 14 considered most severe by the participant. Generalized ordered logit models were then estimated to examine risk factors for USE since age 14, using GOLOGIT2 in STATA version 9.2 (Williams, 2006). This procedure utilizes information regarding the order of the three categories (i.e., the greater severity of forced sex/attempts as compared with the other measured forms of USE) and allows the proportional odds assumption to be relaxed for variables that fail to meet it.

We estimated the bivariate relationship between USE before and since age 14 and two multivariate models. The first model adjusted for witnessing domestic violence before age 14 and socioeconomic/demographic factors: age, parental education, urbanicity, and non-intact family of origin. The second model added variables regarding two choices made by the participant: whether he had lived away from his parents while attending college and whether he had ever had consensual sex. Given the potential for extended abuse by the same person (i.e., before and since age 14), we also re-estimated the second model excluding the 8 cases in which the perpetrator in the incident before age 14 considered most severe by the participant was identified as a family member or partner of a family member. We then generated descriptive statistics for contexts of the incident since age 14 viewed by the participant as most severe, as well as barriers to disclosure. Finally, we conducted cross-tabulation analyses to examine patterns of joint occurrence since age 14 of USE (forced sex/attempts, other forms of unwanted sexual contact) with: (1) PDV and (2) coerced condom non-use.

RESULTS

Sample Descriptive Statistics

The participants ranged in age from 17 to 30 years, with a median of 20 years. Approximately 80.3% lived in Santiago or another large urban area at age 14. A cross-tabulation of urbanicity and living arrangements showed a strong association: 90.7% of the participants who lived in an urban area at age 14 resided in the parental home while attending college (p < .01). Other descriptive statistics are shown in Table 1. Approximately 9.4% of participants reported USE before age 14; the perpetrators in the incidents viewed as most severe by the participants were most commonly a friend (23.1%) and a family member or partner of family member (20.5%). Other perpetrators were a boyfriend/girlfriend (15.4%), sexual partner (2.5%), classmate (7.7%), teacher (2.6%), stranger (2.6%), and “other adult” (15.4%); the remaining cases correspond to no recall (5.1%) and no response (5.1%).

Table 1.

Descriptive statistics for explanatory variables (N = 416)

Variable
Median
Age (years) 20.0
Percentages
USE before age 14 9.4
Witnessed domestic violence before age 14
 Rarely 26.2
 Several times 8.2
 Often 1.7
Low parental education 34.1
Large city at age 14 80.3
Non-intact family at age 14 20.7
Residence away from parents during college years 19.5
Ever had consensual sex 69.0
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Note. We imputed the modal category for cases with missing values on the control variables. The variables on consensual sex and witnessing domestic violence had 19 and 20 cases with missing data, respectively. We included dummy variables for missing data on these two variables in preliminary regressions; they were insignificant and dropped from analyses. Three or fewer cases were imputed for the other control variables.

Prevalence of USE Since Age 14

Panel A in Table 2 shows the percentage of participants who responded affirmatively to each USE item; some participants reported more than one form of USE. Approximately 77.1% of incidents of forced sex since age 14 occurred when the participant was under the influence of alcohol or other drugs, unable to stop what was happening. Panel B classifies participants by the most severe form of USE since age 14. Overall, 20.4% of the sample reported some form of USE in this period. The most severe type was physically-forced sex for 0.2% of the sample and forced sex through verbal coercion or while intoxicated for 10.1%. The dependent variable used in the multivariate models was based on the mutually exclusive categories in Panel B: it equals 3 (forced sex/attempts, 11.7%), 2 (other forms of USE, 8.7%) or 1 (no USE, 79.6%).

Table 2.

Percentage of participants reporting USE since age 14

Percentage
(N = 416)
Panel A: Forms experienceda
Physically-forced sex 0.2
Verbally-forced sex 2.4
Forced sex while intoxicated 8.9
Attempts 4.1
Other forms of USE 13.5
None 79.6
Panel B: Most severe form experiencedb
Physically-forced sex 0.2
Verbally-forced sex or forced sex while intoxicated 10.1
Attempts 1.4
Other forms of USE 8.7
None 79.6
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a

The categories in Panel A are not mutually exclusive, as some participants reported more than one form of USE since age 14.

b

The categories in Panel B are mutually exclusive.

Risk Factors

Generalized ordered logit regression results are shown in Table 3. Brant tests showed that only the urbanicity variable violated the proportional odds assumption (p < .05); the corresponding odds ratios were therefore allowed to vary across categories. The bivariate model shows that USE before age 14 was associated with 4.84 times higher odds of USE since age 14 (95% CI 2.51-9.15, p < .01). The AOR increased when controls for family background (Model 1) and living arrangements and consensual sexual activity (Model 2) were added, but pairwise comparisons showed no significant differences between the underlying coefficients.

Table 3.

Generalized ordered logit models assessing associations between USE before age 14 and USE since age 14 (N = 416)

Bivariate Multivariate
Measure Model 1 Model 2
USE before age 14 4.84 (2.51-9.15) ** 5.52 (2.86-10.67) ** 6.38 (3.22-12.65) **
Witnessed domestic violence before age 14
 Rarely 1.25 (0.71-2.18) 1.25 (0.70-2.21)
 Several times 1.97 (0.89-4.38) † 2.04 (0.91-4.60) †
 Often 0.34 (0.04-3.20) 0.26 (0.03-2.50)
Age 0.99 (0.90-1.10) 0.96 (0.86-1.06)
Low parental education 1.08 (0.64-1.83) 1.22 (0.71-2.10)
Large city at age 14
 1 vs 2 and 3 0.60 (0.33-1.10) † 0.71 (0.35-1.45)
 1 and 2 vs 3 0.38 (0.19-0.75) ** 0.44 (0.20-0.97) *
Nonintact family at age 14 1.85 (1.03-3.30) * 2.00 ( 1.10-3.61) *
Residence away from parents during
college years		 1.39 (0.68-2.84)
Ever had consensual sex 3.68 (1.87-7.21) **
Log L −257.72 −250.28 −241.00
χ2 (df) 23.59 (1)** 36.67 (9)** 48.24 (11) **
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Note. The dependent variable equals 3 (forced sex/attempts), 2 (less severe forms of USE), or 1 (no USE).

**

p <. 01

*

p < .05

†

p ≤ .10

The perpetrator of the most severe incident in childhood was a family member or partner of a family member in 8 cases (20.5%). When we re-estimated Model 2 excluding these cases (to address the concern that our results might be driven by revictimization by the same person), the AOR decreased but remained large and statistically significant (AOR 4.45, 95% CI 2.03-9.75, p < .01).

Regarding the control variables, Model 1 shows that witnessing domestic violence “several times” in childhood was associated in the predicted direction with odds of USE since age 14 (AOR 1.97, 95% CI 0.89-4.38, p = .10) but the results did not reach statistical significance. The odds of USE since age 14 were higher for those who grew up in a non-intact family (AOR 1.85, 95% CI 1.03-3.30, p < .05). Urbanicity was associated with substantially lower odds of USE, particularly forced sex or attempts (AOR 0.38, 95% CI 0.19-0.75, p < .01).

Model 2 shows that the odds of USE since age 14 were positively associated with having initiated consensual sex (AOR 3.68, 95% CI 1.87-7.21). The association with residence away from the parental home was positive but not significant. Given the multicollinearity between urbanicity and college living arrangements noted earlier, we estimated another regression (not shown) including all variables in Model 2 except urbanicity. In this regression, the AOR associated with living away from parents was marginally significant (AOR 1.75, 95% CI 0.96 - 3.21, p < .10).

Most Severe Incident Since Age 14: Contexts and Disclosure

Participants who reported USE since age 14 (N = 85; 20.4%) were asked questions about the contexts and disclosure of the incident since age 14 they viewed as most severe; the response rate for these items was approximately 80.0%. The perpetrator was most commonly identified as a friend, other student, or acquaintance (50.7%). Other common assailants were boyfriend/ girlfriend or ex-boyfriend/ex-girlfriend (20.9%) and a date (13.4%). The remaining cases were reported to have involved strangers (7.5%), family members (6.0%) and teachers (1.5%). The most commonly reported locations were a party (49.3%) and the perpetrator or victim’s home (29.9%). Consumption of alcohol and/or other drugs by the victim only, perpetrator only, or both, was involved in 8.7%, 11.6%, and 43.5% of cases, respectively.

Among participants who indicated USE since age 14, 74.3% told someone about the incident; 65.7% told a friend, 2.9% told a psychologist or social worker, and none told a physician. None of the incidents of forced sex or attempts were reported to the police; the most frequently-endorsed reason for not doing so was “I did not think that what happened was sufficiently serious, or a crime” (50.0%). Other salient reasons were “I wasn’t sure that the person who did this really wanted to hurt me” (14.3%); “I felt ashamed” (14.3%); “fear of revenge from the person who did this” (9.5%), and “if I told the police, they would not respond” (7.1%).

Sex of Perpetrators Before and/or Since Age 14

Among participants who reported any lifetime USE (N = 108), 68.0% indicated that the perpetrators had been “women only”; the other response options were “women and men” (11.5%) and “men only” (20.5%). The response rate for this survey item was 72.2%.

Co-Victimization Since Age 14

Table 4 shows findings regarding co-victimization, i.e., the joint occurrence since age 14 (not necessarily in the same incident or by the same aggressor) of USE with (1) PDV; and (2) coerced condom non-use (examined in the subsample of participants who reported ever having had consensual vaginal or anal sex). The percentage of participants reporting PDV was 56.3% among those for whom forced sex/attempts was the most severe form of USE since age 14; 46.9% among those for whom the most severe form was less serious; and 33.2% among those who reported no USE (p < .01) (Panel A). The percentage of participants reporting coerced condom non-use was 30.2% among those for whom forced sex/attempts was the most severe form of USE since age 14; 23.1% among those for whom the most severe form was less serious; and 12.6% among those who reported no USE( p = .01) (Panel B).

Table 4.

Associations between USE since age 14 and other forms of coercion since age 14

PANEL A: PDV Yes No
USE
 Forced sex /attempts 27
56.3%		 21
43.7%		 N = 48
100%
 Other forms of USE 15
46.9%		 17
53.1%		 N = 32
100%
 None 101
33.2%		 203
66.8%		 N = 304
100%
 2 = 10.8 (2 df) p < .01
PANEL B: Coerced condom non-use Yes No
USE
 Forced sex /attempts 13
30.2%		 30
69.8%		 N = 43
100%
 Other forms of USE 6
23.1%		 20
76.9%		 N = 26
100%
 None 25
12.6%		 173
87.4%		 N = 198
100%
χ2 = 8.87 (2 df) p = .01
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Note. The sample for Panel A is N = 384, obtained after eliminating from the base sample 32 cases with missing data on PDV. The sample for Panel B is N = 267, obtained after deleting from the base sample 148 cases corresponding to participants who indicated never having had consensual sex and one case with missing data on coerced condom non-use.

DISCUSSION

Main Findings and Implications

Prevalence of USE since age 14

In our sample of male students enrolled in General Education courses at a large public university in Chile, we found that approximately one-fifth of the participants reported some form of USE since age 14. With regard to rape, the legal definition in Chile is vaginal, anal, or oral penetration of a person over age 14 by force or threats, or while the victim is intoxicated or otherwise incapacitated. Penetration of someone 14 years of age or younger is defined as rape even if the experience was “consensual.” As a first approximation, our analysis suggests a forced sex prevalence of 0.2% based on a narrow definition limited to physical force and a forced sex prevalence of 10.3% if verbally-coerced sex and coerced sex while intoxicated are included. However, our survey items did not differentiate between instances of coercion where men were penetrated vs. where they performed a penetrative act that they perceived as coerced; these latter instances, while potentially distressing and harmful, do not meet the Chilean legal definition of rape.

Risk factors

We found that 9.4% of participants reported USE before age 14. This prevalence estimate was consistent with findings in a review of studies conducted in 21 countries at various stages of economic development: prevalence of CSA reported by men ranged from 0 to 60%, with most studies providing estimates below 10% (Pereda, Guilera, Forns, & Gómez-Benito, 2009).

In our sample, USE before age 14 was associated with 5.52 and 6.38 greater adjusted odds of USE since age 14 in Models 1 and 2, respectively. A meta-analytic review of CSA and revictimization in women found that studies that used the most restrictive CSA definitions reported the largest effect sizes (Roodman & Clum, 2001). To the extent that a similar pattern may hold for men, our study–based on a broad measure of USE before age 14 that included relatively “minor” forms of coercion–likely resulted in a weaker estimated association than would have been obtained with a more restrictive definition including only more physically severe forms of abuse. It is thus particularly noteworthy that we found the adjusted odds of USE since age 14 to be approximately six times greater for participants who reported USE before age 14 than for those who did not. As noted earlier, an AOR estimate of 5.5–a similar magnitude– was reported in a national U.S. study of adult men (Desai et al., 2002), using a CSA measure that was limited to the most severe forms of abuse; recent research based on data from other countries has also found evidence of a strong association in men between CSA and subsequent USE (Hines, 2007) and intimate partner victimization (Daigneault et al., 2009). Our results thus add to a growing international literature that stresses the importance of strengthening public health efforts to prevent, identify, and respond to CSA.

With regard to other variables included in our analysis, growing up in an urban area and in an intact family were associated with lower odds of reporting USE since age 14, and there was some evidence suggestive of witnessing domestic violence in childhood as a risk factor. Consistent with Chilean norms, we found that only one-fifth of participants had primarily lived away from the parental home while pursuing college studies; the study findings suggest that these students may have elevated odds of USE, meriting special attention in prevention efforts. Participants who had initiated consensual sex were also found to have higher odds. It should be noted that the coefficients associated with choices on place of residence and consensual sex may partly reflect unobserved characteristics of the participants that influence vulnerability to USE.

Most severe incident since age 14: contexts and disclosure

Our finding that substance use by the victim, perpetrator, or both was involved in almost two-thirds of the incidents considered by the participant to have been most severe underscores the importance of incorporating drug and alcohol education programs in interventions for sexual assault prevention/risk reduction and vice–versa. Also relevant to the development of interventions are our findings that the assailant was identified as a friend/acquaintance or date/partner in 50.7% and 34.3% of such incidents, respectively.

None of the participants who indicated experience of forced sex or attempts notified the police, in accordance with earlier studies that found USE in men to be a notably underreported crime (Sable et al., 2006; Tewksbury, 2007). Also consistent with earlier study findings (Davies, 2002; Donnelly & Kenyon, 1996; Sable et al., 2006), 14.3% of these participants cited “shame” as a reason for not reporting the USE. Almost two-thirds indicated that they did not report the most severe incident since age 14 to the police because they did not think that what happened was sufficiently serious or a crime or that the person who did it had not meant to hurt them. Such attitudes, minimizing the reality or significance of men’s USE, may also contribute to reducing men’s seeking of health care or psychological support for these experiences. In this study, only 2.9% of participants who reported USE since age 14 told a mental health professional about the most severe incident and none contacted a physician. Friends were by far the most common confidants, suggesting the importance of bystander education programs which aim to teach participants how to identify signs of risk in community members, intervene where feasible, and be an effective ally for survivors (Banyard, Plante, & Moynihan, 2004; Koss & Harvey, 1991).

Efforts to design prevention programs that dispel male rape myth beliefs and promote health-supportive gender role attitudes among the general population and service providers are also important items in the agenda for public health practice. Such work is particularly needed in socially conservative societies such as that of Chile; this conservatism is evident in a range of Chilean study findings. For example, in the 2000 national survey mentioned earlier, only 3.7% of male participants reported “approving” of male homosexuality (Goldstein et al., 2000). Another Chilean national survey of adults in 2001 found substantial adherence to traditional gender roles, with men, less-educated participants, and older participants holding the most traditional views (SERNAM, 2002).

Laws and programs have both reflected and reinforced this sociocultural environment, e.g., divorce was legalized in 2004, making Chile the last Western country to do so, and the first workplace equal pay law was passed in 2009. A recent national Healthy Universities initiative in Chile, designed to promote healthy behaviors in university students and developed in collaboration with the Chilean Ministry of Health, made no mention of sexual assault or dating violence (Lange & Vio, 2006). To our knowledge, there are presently no established campus programs for sexual assault prevention in Chile, and there are no commonly-understood Spanish-language terms for “date rape” or “acquaintance rape.” We theorize that conservative reluctance to publicly address “sexuality” in young people extends to reluctance to discuss and address “sexual” assault.

Sex of Perpetrators

Approximately 32.0% of study participants who reported any lifetime USE (before and/or since age 14) indicated that some or all of the perpetrators were men. A similar result was found in a study of university students in Italy, where one-third of lifetime USE reported by men involved male perpetrators (Romito & Grassi, 2007). Focusing on the complement of this statistic, approximately two-thirds of participants who reported any lifetime USE indicated female perpetrators only. Related research based on two community samples of young heterosexual men in Germany found that 25.1-30.1% of participants had experienced female-perpetrated USE and that most men described these incidents as “moderately upsetting” (Krahé, Scheinberger-Olwig, & Bieneck, 2003); as emphasized by the authors of this study, it is unclear whether these findings (and similar earlier findings in the literature) reflect a genuine lack of strong adverse effects, or denial/minimization. A possible contributing factor is the inclusion of relatively “minor” incidents, such as forced kisses, in some USE definitions (Peterson et al., 2011). In addition, psychological impacts of coercion perpetrated by women may be mitigated by the fact that sexual activity with a woman, even under circumstances of coercion, is congruent with the stereotypical male role, unlike sexual activity with a man (Struckman-Johnson & Struckman-Johnson, 1994).

Co-victimization since age 14

In this study, participants who reported forced sex or attempts since age 14 were significantly more likely than those who did not to also report PDV and coerced condom non-use in this period, consistent with prior study findings for adolescent girls and young adult women (Lehrer et al., 2010; Smith et al., 2003; White, 2009). Although the survey instrument did not assess specific means used to coerce the participant to not use a condom within the context of a voluntary encounter, these may have included verbal pressure to not use a condom, outright refusal to have sex with a condom, and /or some physical demonstration of unwillingness to use a condom.

Experiences of co-victimization may partly reflect background factors such as CSA that independently affect the risk of each form of subsequent victimization; in addition, experiencing one form of victimization during adolescence and young adulthood may augment vulnerability to another. Our findings suggest that these various forms of violence should be addressed jointly in prevention programs and that healthcare providers interacting with young men who report any of these forms of violence should inquire about the others.

Limitations and Directions for Future Research

The study sample included students enrolled in all educational programs of the university, but was not a representative sample; the findings thus cannot be generalized to the full student body. USE before and since age 14 were likely underreported due to factors including shame, denial, recall error, and failure to interpret coercion or abuse as such. Our items regarding USE before age 14 did not inquire about the age difference between the perpetrator and child, as do some CSA measures (Hulme, 2004; Senn et al., 2008); our measure, therefore, likely captured some cases of peer-level sexual interaction, which may have fewer long-term sequelae than those involving older perpetrators with substantially greater power (i.e., adults or older youth). Hence, our estimate of the association between childhood USE and USE since age 14 may be biased downward. In addition–as is the case for most previous studies in the field–our survey did not collect information on participants’ sexual orientation or sex of the perpetrator in the most severe incident since age 14, limiting our ability to interpret the findings; doing so required items that were beyond what was culturally acceptable for an initial study in a socially conservative setting.

In a similar effort toward contextual sensitivity, our survey assessed USE in men with a small set of general questions which were the same as those used for female participants. Men’s responses must be interpreted as reflecting their perceptions when presented with such items; the lack of behavioral specificity regarding whether a penetrative act was unwillingly performed vs. sustained by the participant is a limitation of our study. Although this limitation is widespread among earlier studies in the literature (e.g., Choudhary et al., 2010; Daigneault et al., 2009; Elliott et al., 2004; Hines, 2007), it has received little attention.

Further qualitative research should aim to gain a better understanding of men’s perceptions of sexually coercive situations with male and female perpetrators; these efforts will help guide the development of sexual assault risk reduction programs for men. It would also be desirable to conduct further quantitative inquiry using the revised SES (Koss et al., 2007), which contains items that were developed with behavior-specific wording to elicit information on a range of unwanted sexual activities; this will make it possible to base men’s rape prevalence estimates with more specificity on acts that involve sustaining forced penetration, leaving less leeway for men’s individual perceptions of what constitutes “forced sex.”

Overall, the findings of this study underscore the importance of directing additional public health attention to USE in adolescent boys and young adult men in Chile and other countries. They also point to a need for further research on the joint occurrence of PDV and USE and resultant HIV/STI risk for young men, with samples of heterosexually active men and MSM.

ACKNOWLEDGEMENTS

This project was supported by Award Number T32MH019105 from the National Institute of Mental Health. The content of this article is solely the responsibility of the authors and does not necessarily represent the official views of the National Institute of Mental Health or the National Institutes of Health. Shari Dworkin, Ph.D., Michael Scarce, M.A., and Janet Turan, Ph.D., provided valuable comments on an earlier draft. We are also indebted to the Editor and three anonymous referees for helpful suggestions.

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