5


Selected Other Surveys on
Rape and Sexual Assault

Chapter 1 describes two perspectives for measuring rape and sexual assault through surveys, the criminal justice perspective, and the public health perspective. The first perspective focuses on measuring criminal victimizations as exemplified in the National Crime Victimization Survey (NCVS), described in Chapter 4. It provides counts of criminal victimizations in a specified period of time, calculates the victimization rates for that period, and calculates the change in rate from a previous period. The second perspective, public health, focuses more broadly on sexual violence and the effects of that violence on the physical and emotional health of its victims.

The panel believes that the two approaches have some basic differences in purpose, and this purpose differential has led to certain methodological decisions as the surveys were designed. The report maintains this dichotomy to help clearly explain these conceptual frameworks. As the report proceeds, the panel concludes that some of the design decisions in the NCVS might be improved by adopting some of the methodological approaches used by the public health approach.

This report does not try to make recommendations about how the surveys designed under the public health approach might be improved. With limited time and resources, the panel made the decision to focus its analysis on the NCVS with the intent to make specific recommendations to the Bureau of Justice Statistics (BJS) for future estimation of rape and sexual assault. Two of the public health surveys are more than 16 years old and one is almost 25 years old. Thus it was a low priority to try to recommend ways these older surveys could have been improved, and it would have been very difficult to obtain the needed metadata to make those



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5 Selected Other Surveys on Rape and Sexual Assault C hapter 1 describes two perspectives for measuring rape and sexual as- sault through surveys, the criminal justice perspective, and the public health perspective. The first perspective focuses on measuring crimi- nal victimizations as exemplified in the National Crime Victimization Survey (NCVS), described in Chapter 4. It provides counts of criminal victimiza- tions in a specified period of time, calculates the victimization rates for that period, and calculates the change in rate from a previous period. The second perspective, public health, focuses more broadly on sexual violence and the effects of that violence on the physical and emotional health of its victims. The panel believes that the two approaches have some basic differences in purpose, and this purpose differential has led to certain methodological decisions as the surveys were designed. The report maintains this dichotomy to help clearly explain these conceptual frameworks. As the report pro- ceeds, the panel concludes that some of the design decisions in the NCVS might be improved by adopting some of the methodological approaches used by the public health approach. This report does not try to make recommendations about how the surveys designed under the public health approach might be improved. With limited time and resources, the panel made the decision to focus its analysis on the NCVS with the intent to make specific recommendations to the Bureau of Justice Statistics (BJS) for future estimation of rape and sexual assault. Two of the public health surveys are more than 16 years old and one is almost 25 years old. Thus it was a low priority to try to recommend ways these older surveys could have been improved, and it would have been very difficult to obtain the needed metadata to make those 71

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72 ESTIMATING THE INCIDENCE OF RAPE AND SEXUAL ASSAULT recommendations. The panel believes that a thorough error analysis of the National Intimate Partner and Sexual Violence Survey (NISVS) would be useful because it is likely to be conducted on a continuing basis. The panel hopes that the Centers for Disease Control and Prevention (CDC) will com- mission such an analysis. The two approaches differ in terms of goals and survey methodolo- gies. For the NCVS, there are two key elements: the classification of a victimization as criminal or noncriminal (according to criteria from the BJS), and the determination of whether the victimization occurred within a specified reference period. In the public health approach, those elements are less important; instead, the key focus is trying to measure the effect of victimizations. However, surveys based on the public health perspective still provide measures (often “lifetime measures”) of rape and sexual assault, as discussed below. Because of the basic conceptual difference in their ap- proach, their estimated victimization rates would be expected to be and are different from those in the NCVS. This chapter provides an overview of four significant surveys that generally fall under the public health approach: the National Women’s Study (NWS), the National Violence Against Women Study (NVAWS), the National College Women Sexual Victimization (NCWSV) Study, and the National Intimate Partner and Sexual Violence Survey (NISVS). This chapter, like Chapter 4, does not try to assess the quality of these surveys; rather, it provides summary descriptions of the four surveys. By including these specific surveys in this descriptive chapter, the panel is not suggest- ing that the estimates from these surveys represent truth or are somehow a “gold standard.” Nor did we include all relevant studies of rape and sexual assault.1 Nevertheless, this selection provides an overview of other work done in this area. Chapter 6 subsequently provides some reasonable comparison among the surveys, and with the NCVS and the Uniform Crime Reports (UCR) Program. NATIONAL WOMEN’S STUDY (1989-1991) The NWS, funded by the National Institute of Drug Abuse, was one of the first of surveys that provided national-level measures of rape and sexual assault from the public health perspective. It was conducted in 1989-1991 with a national sample of 4,008 women. The results were published in 1  The reader may be aware of additional studies that are relevant to these discussions. The panel identified four studies that it describes in this chapter, and Appendix D provides more details on these four studies and includes three other studies not discussed in the report proper. The panel did not attempt to make a comprehensive list of such studies because it needed to keep its focus on the examination of the NCVS.

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SELECTED OTHER SURVEYS ON RAPE AND SEXUAL ASSAULT 73 Rape in America: Report to the Nation (Kilpatrick, Edmunds, and Seymour, 1992).2 Methodology The NWS was a longitudinal survey of women aged 18 years of age and older, divided into two parts: a sample of all adult women (sample size of 2,008) and an oversample of younger women, those between the ages of 18 and 34 (sample size of 2,000). The households were selected using a two-stage area probability sampling procedure. In the first stage, the United States was divided into four geographic regions and three census-based size-of-place strata, which resulted in 12 mutually exclusive and exhaustive groupings of the total U.S. geographic area. In the second stage, random digit dialing (RDD) was used to select households within each geographic area. After reaching a household, the interviewer ascertained the number of adult females in the household and randomly selected one for an interview. Data collection was conducted in three waves, following respondents from wave 1 through two additional waves. The survey protocol used only female interviewers. All three waves assessed women’s lifetime experience of forcible rape. Wave 2 assessed forcible rapes that occurred between the baseline and second interview, while wave 3 assessed forcible rapes that occurred between the second and third interviews. Wave 1 collected infor- mation about the lifetime prevalence of rape, along with descriptive informa­ tion about rape incidents.3 Wave 2 was conducted 1 year later and asked respondents about prevalence of rape during the previous year. Thus, the 12-month recall questions were bounded by the wave 1 interview. Wave 3 collected information about rape victims’ concerns, medical examinations, willingness to report future rapes to police, and opinions about the impact of protection of their names from media disclosure. Potential mental health problems were assessed during each of the three waves. Wave 1 was completed with a cooperation rate of 85 percent and a response rate of 34 percent.4 For wave 2, 81 percent of the wave 1 partici- 2  Dean Kilpatrick was the principal investigator on this study. Sample selection and survey operations were performed by the firm of Schulman, Ronca, and Bucuvalas, Inc. (SRBI), a survey research organization based in New York City. 3  The NWS also included some screening questions for other forms of contact and non­ contact pressure for sexual activity (see Resnick et al., 1993). 4  The cooperation rate (percentage of those contacted that agreed to cooperate) was calcu- lated as a part of the original report and is documented there. The panel used the original case dispositions to calculate a response rate using Standard 4 of the American Association of Public Opinion Research (n.d.). Cooperation rates are generally calculated once a poten- tial respondent has been contacted and do not reflect sample screen outs that occur before a respondent is contacted.

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74 ESTIMATING THE INCIDENCE OF RAPE AND SEXUAL ASSAULT pants were located and reinterviewed. The data collected were weighted to align with Census Bureau projections of the number of adult females by age and race. The NWS questionnaire was different from the one used in the Na- tional Crime Survey (NCS)5 in that it contained explicitly worded ques- tions about sexual intercourse. It also included questions about oral and anal rape. The NWS also attempted to look at major post-incident mental health problems such as depression, post-traumatic stress disorder, suicide attempts, and alcohol- and drug-related problems. Questions Given its public health context and perspective, the survey included a broad range of questions (Kilpatrick, Edmunds, and Seymour, 1992, p. 1): In addition to gathering information about forcible rapes that occurred throughout women’s lifetimes, the National Women’s Study also assessed such major mental health problems as depression, Post-traumatic Stress Disorder, suicide attempts, as well as alcohol and drug-related problems and consumption. Unlike the NCVS, the NWS did not use separate screening and incident reports. The following questions were used to capture incidents of rape in the NWS (Kilpatrick, Edmunds, and Seymour, 1992, p. 15): Women do not always report such experiences to police or dis- cuss them with family or friends. The person making the advances isn’t always a stranger, but can be a friend, boyfriend, or even a family member. Such experiences can occur anytime in a woman’s life—even as a child. Regardless of how long ago it happened or who made the advances. . . • H  as a man or boy ever made you have sex by using force or threatening to harm you or someone close to you? Just so there is no mistake, by sex we mean putting a penis in your vagina. • H  as anyone ever made you have oral sex by force or threat of harm? Just so there is no mistake, by oral sex, we mean that a man or boy put his penis in your mouth or some- body penetrated your vagina or anus with his mouth or tongue. • H  as anyone ever made you have anal sex by force or threat of harm? 5  The NCS was the predecessor to the current NCVS; see Chapters 1 and 4.

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SELECTED OTHER SURVEYS ON RAPE AND SEXUAL ASSAULT 75 • H  as anyone ever put fingers or objects in your vagina or anus against your will by using force or threat? Results The NWS estimated prevalence of rape victimization rather than esti- mating the number of incidences of rape as was measured by the NCS. (At- tempted rape and other types of sexual assault were measured in the survey but these estimates were not included in the report.) The NWS prevalence estimate was 683,000 adult females per year who were raped in the United States. This total was 5 times higher than the number of incidences esti- mated that same year by the NCS (130,000, which included rape, attempted rape, and other sexual assaults) and almost seven times the number of inci- dences summarized by the UCR system (102,560, which included attempted rape but not other types of sexual assault) (see Figure 5-1). The NWS was one of the first major surveys that provided evidence of undercounting of rape on both the UCR and the NCS. NATIONAL VIOLENCE AGAINST WOMEN STUDY (1995-1996) In the Violence Against Women Act of 1994,6 Congress mandated that the federal government provide a more valid estimate of the magnitude of violence against women, including both rape and stalking. The National Institute of Justice (NIJ) and the CDC partnered, through a grant to the Center for Policy Research, to launch a national survey. The survey was fielded once in 1995 and became known as the NVAWS (see Tjaden and Thoennes, 2000).7 Methodology Like the NWS, the NVAWS was designed around an RDD telephone survey. It was conducted once, from November 1995 to May 1996, target- ing adults, both male and female, covering all households with a landline telephone in 50 states and the District of Columbia. The sample was ad- ministered within the U.S. Census Bureau regions. Interviewers called RDD- selected numbers from a central telephone facility using computer-assisted technology. Nonworking and nonresidential numbers were screened out. 6  The act required the Attorney General to report on the incidence of violence against women including stalking (P.L. 103-322, Section 40610). The act was a part of the larger Omnibus 1994 Crime Control Act. 7  Patricia Tjaden and Nancy Thoennes were the principal investigators on the study. Sample selection and survey operations were performed by SRBI, a survey research organization based in New York City.

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76 ESTIMATING THE INCIDENCE OF RAPE AND SEXUAL ASSAULT UCR 102,660 Source NCS 130,000 NWS 683,000 0 100,000 200,000 300,000 400,000 500,000 600,000 700,000 800,000 Number of Rapes: 1990 FIGURE 5-1 Rapes of females: results from three data sources. NOTES: The data are from the National Women’s Study (NWS), the National Crime Study (NCS; predecessor of the NCVS), and the Uniform Crime Reports (UCR). The NWS estimate is for prevalence of completed rapes (raped at least one time) for females who were 18 years of age and older. The NCS estimates the number of rapes and attempted rapes for females who were 12 years of age and older. The UCR estimate is for both completed and attempted rapes reported to the police, no specific age limit. SOURCE: Kilpatrick, Edmunds, and Seymour (1992, p. 3, Figure 2). Once a residential household was reached, all eligible adults (i.e., women and men 18 years of age and older) in each household were identified. In households with more than one eligible adult, the adult with the most re- cent birthday was selected as the designated respondent. A total of 8,000 women and 8,0058 men were interviewed. All female respondents were interviewed by female interviewers. For male respon- dents, approximately half of the interviews were conducted by female interviewers and half by male interviewers. Bilingual interviewers adminis- tered a Spanish-language version of the questionnaire for Spanish-speaking respondents. Because the survey was conducted only once, there was no initial interview that bounded the 12-month reporting of victimizations. The survey had a 72 percent cooperation rate for females and a 69 percent cooperation rate for male respondents.9 The unweighted response rate, 8  Five completed interviews were subsequently eliminated from the data file during editing because of an excessive amount of incongruous data. 9  The cooperation rate (percentage of contacted individuals who responded) for the NVAWS was calculated by dividing the number of completed interviews (including those that were screened out because they were ineligible) by the total number of completed interviews, screened-out interviews, refusals, and terminated interviews (Tjaden and Thoennes, 2000, p. 4).

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SELECTED OTHER SURVEYS ON RAPE AND SEXUAL ASSAULT 77 calculated based on American Association for Public Opinion Research (AAPOR) Standard 4, was 34 percent (see footnote 4). Questions The NVAWS followed the NWS approach to question formulation, using behaviorally specific words to ask questions about rape. The survey, too, also covered a fairly wide range of topics that included not only rape and attempted rape, but also physical assault experienced as a child by adult caretakers, physical assault experienced as an adult, and stalking. It asked for “detailed information about the characteristics and consequences of victimization for each type of perpetrator identified by the respondent” (Tjaden and Thoennes 2000, p. 1). The following specific questions were asked about rape and attempted rape (Tjaden and Thoennes, 2000, p. 4): 1. Has a man or boy ever made you have sex by using force or threatening to harm you or someone close to you? Just so there is no mistake, by sex we mean putting a penis in your vagina. 2. Has anyone, male or female, ever made you have oral sex by using force or threat of force? Just so there is no mis- take, by oral sex we mean that a man or boy put his penis in your mouth or someone, male or female, penetrated your vagina or anus with their mouth. 3. Has anyone ever made you have anal sex by using force or threat of harm? Just so there is no mistake, by anal sex we mean that a man or boy put his penis in your anus. 4. Has anyone, male or female, ever put fingers or objects in your vagina or anus against your will or by using force or threats? 5. Has anyone, male or female, ever attempted to make you have vaginal, oral, or anal sex against your will, but inter- course or penetration did not occur? The NVAWS used a single-stage classification process to identify rape victims, unlike the two-stage process currently used in the NCVS (see Chapter 4). If a respondent responded yes to one of the above questions, then he or she was classified as a victim of a completed or attempted rape (depending on the question).

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78 ESTIMATING THE INCIDENCE OF RAPE AND SEXUAL ASSAULT Results The survey generated lifetime and 12-month prevalence rates, as well as 12-month incidence rates.10 The survey estimated that 302,091 women and 92,748 men had been raped in the previous 12 months (prevalence), with a total of 987,362 rape victimizations. The victims were women in 89 percent (876,064) of the incidents. The estimated total 12-month incidence rate was 5.1 per 1,000 people (18+ years). But the NVAWS sample of 16,000 women and men interviewed included only 24 women and 8 men who reported having been raped in the past 12 months—a low incidence. Thus, the rela- tive standard errors for incidence rates and for male 12-month prevalence rates are large, above 30 percent (see Table 5-1 for details). NATIONAL COLLEGE WOMEN SEXUAL VICTIMIZATION STUDY (1997) Sexual violence has been, and continues to be, a particular problem on college campuses (Diamond and Emerson, 2012; Fisher, Cullen, and Turner, 2000; Karjane, Fisher, and Cullen, 2005). In the Student Right-to-Know and Campus Security Act of 1990 (P.L. 101-542), Congress expressed concern about the seriousness of sexual violence on college campuses and highlighted the importance of having accurate information about such violence. The act mandated that colleges and universities participating in federal student aid programs “prepare, publish, and distribute, through ap- propriate publications or mailings, to all current students and employees, and to any applicant for enrollment or employment upon request, an an- nual security report” (20 USC Section 1092). The report was required to include campus security policies and campus crime statistics. The NCWSV (Fisher, Cullen, and Turner, 2000) was a response to those general concerns and the specific legislation. It was funded by the National Institute of Justice of the U.S. Department of Justice and conducted once, in 1997.11 Methodology The NCWSV was based on a national sample of 4,446 women who were attending 2- or 4-year colleges or universities during fall 1996. The design had two stages: sampling institutions and then sampling female 10  An incidence rate is based on the total number of individual victimizations that occurred during the reference period. A prevalence rate is based on the total number of victims that experienced one or more victimizations during the reference period. 11  The principal investigators were Bonnie Fisher and Francis Cullen. SRBI, a survey research organization based in New York City, conducted the survey.

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TABLE 5-1  Estimated Number of Rape, Physical Assault, and Stalking Victimizations Annually by Gender of Victim, National Violence Against Women Study Percentage of Estimated Average Number of Estimated Annual Rate of Type of Sample Reporting Number of Victimizations Number of Victimization Victimization an Incident Victims per Victima Victimizations per 1,000 Persons Women, 18+ (100,697,000) sample size = 8,000 Rape 0.3 302,091 2.9b 876,064b 8.7 Physical assault 1.9 1,913,243 3.1 5,931,053 58.9 Stalking 1.0 1,006,970 1.0 1,006,970 10.0 Men, 18+ (92,748,000) sample size = 8,000 Rape 0.1 92,748 1.2b 111,298b 1.2 Physical assault 3.4 3,153,432 2.5 7,883,580 85.0 Stalking 0.4 370,992 1.0 370,992 4.0 Total,c 18+ (193,445,000) sample size = 16,000 Rape 0.2 394,839 2.5 987,362 5.1 aThe standard error of the mean is 1.4 for female rape victims, 0.2 for female physical assault victims, 0.5 for male rape victims, and 0.2 for male physical assault victims. bRelative standard error exceeds 30 percent. cCalculated from statistics in table about males and females. SOURCE: National Violence Against Women Study (Tjaden and Thoennes, 2006, p. 15). 79

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80 ESTIMATING THE INCIDENCE OF RAPE AND SEXUAL ASSAULT students in the selected institutions. The population of eligible institutions consisted of schools with at least 1,000 students. The list of institutions was stratified by the size of the total student enrollment (1,000-2,499; 2,500- 4,999; 5,000-19,999; 20,000 or more) and the school’s location (urban, suburban, and rural). Schools were randomly chosen using a probability proportional to the total female enrollment. For each selected institution, the American Student List Company provided a list of female students at- tending the institution in the fall of 1996. (The company also provided the school address and telephone number for each selected student.) Using this as a sampling frame, a random sample of female students was selected. The survey was conducted between February and May 1997. Each sampled student was sent a presurvey letter 2 weeks prior to a telephone contact by a female interviewer, who called from a centralized facility. The interviewers used a computer-assisted telephone interviewing system (CATI). The response rate was 67.1 percent;12 the reported cooperation rate was 85.6 percent. To limit potential telescoping, a reference period for recall was estab- lished that would have a clear starting point for those students—beginning of school in fall 1996. Because the interviews were conducted the following February through May, the reference period was approximately 7 months long. The NCWSV measured sexual victimization using the two-stage mea- surement format of the NCVS (see Chapter 4), which involves a screener questionnaire followed by a detailed incident report, but the screener’s questions were very different from those in the NCVS. Drawing from both the NWS and the NVAWS, the NCWSV’s screener questionnaire contained 10 behaviorally specific screen questions that sought to assess whether re- spondents had experienced a range of sexual victimizations (Fisher, Cullen, and Turner, 2000, p. 6):   1. Since school began in the fall 1996, has anyone made you have sexual intercourse by using force or threatening to harm you or someone close to you? Just so there is no mistake, by intercourse I mean putting a penis in your vagina.   2. Since school began in the fall 1996, has anyone made you have oral sex by force or threat of harm? By oral sex, I mean did someone’s mouth or tongue make contact with your vagina or anus or did your mouth or tongue make contact with someone else’s genitals or anus.   3. Since school began in the fall 1996, has anyone made you have anal sex by force or threat of harm? By anal sex, I mean putting a penis in your anus or rectum? 12  The panel recalculated the response rate on the basis of AAPOR Standard 4: see footnote 4.

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SELECTED OTHER SURVEYS ON RAPE AND SEXUAL ASSAULT 81   4. Since school began in the fall 1996, has anyone ever used force or threat of harm to sexually penetrate you with a foreign object? By this, I mean, for example, placing a bottle or finger in your vagina or anus?   5. Since school began in fall 1996, has anyone attempted but not succeeded in making you take part in any of the unwanted sexual experiences that I have just asked you about? For example, did anyone threaten or try but not succeed to have vaginal, oral, or anal sex with you or try unsuccessfully to penetrate your vagina or anus with a foreign object or finger?   6. Not counting the types of sexual contact already mentioned, have you experienced any unwanted or uninvited touching of a sexual nature since school began in fall 1996? This includes forced kiss- ing, touching of private parts, grabbing, fondling, and rubbing up against you in a sexual way, even if it is over your clothes.   7. Since school began in fall 1996, has anyone attempted but not suc- ceeded in unwanted or uninvited touching of a sexual nature?   8. Since school began in fall 1996, has anyone made or tried to make you have sexual intercourse or sexual contact when you did not want to by making threats of nonphysical punishment, such as low- ering a grade, being demoted or fired from a job, damaging your reputation, or being excluded from a group for failure to comply with requests for any type of sexual activity?   9. Since school began in fall 1996, has anyone made or tried to make you have sexual intercourse or sexual contact when you did not want to by promises of rewards, such as raising a grade, being hired or promoted, being given a ride or class notes, or getting help with coursework from a fellow student if you complied sexually? 10. Since school began in fall 1996, has anyone made or tried to make you have sexual intercourse or sexual contact when you did not want to by simply being overwhelmed by someone’s continual pestering and verbal pressure? The NCWSV used these screening questions and subsequent incident reports to categorize and measure 12 types of sexual victimizations (see Table 5-2). In addition to the victimization measures, other questions cov- ered a range of factors including stalking, respondents’ demographic char- acteristics, lifestyle, routine activities, living arrangements, and prior sexual victimizations. Secondary data sources were used to measure the charac- teristics of the schools the respondents attended (e.g., size of enrollment, location, crime rate).

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82 ESTIMATING THE INCIDENCE OF RAPE AND SEXUAL ASSAULT TABLE 5-2  Types of Victimizations Measured on the National College Women Sexual Victimization Study Type of Victimization Definition Completed rape Unwanted completed penetration by force or the threat of force. Penetration includes penile-vaginal, mouth on your genitals, mouth on someone else’s genitals, penile- anal, digital-vaginal, digital-anal, object-vaginal, and object-anal. Attempted rape Unwanted attempted penetration by force or the threat of force. Penetration includes penile-vaginal, mouth on your genitals, mouth on someone else’s genitals, penile- anal, digital-vaginal, digital-anal, object-vaginal, and object-anal. Completed sexual coercion Unwanted completed penetration with the threat of non- physical punishment, promise of reward, or pestering/ verbal pressure. Penetration includes penile-vaginal, mouth on your genitals, mouth on someone else’s genitals, penile- anal, digital-vaginal, digital-anal, object-vaginal, and object-anal. Attempted sexual coercion Unwanted attempted penetration with the threat of non- physical punishment, promise of reward, or pestering/ verbal pressure. Penetration includes penile-vaginal, mouth on your genitals, mouth on someone else’s genitals, penile- anal, digital-vaginal, digital-anal, object-vaginal, and object-anal. Completed sexual contact Unwanted completed sexual contact (not penetration) with with force or threat of force force or threat of force. Sexual contact includes touching; grabbing or fondling of breasts, buttocks, or genitals, either under or over your clothes; kissing; licking or sucking; or some other form of unwanted sexual contact. Completed sexual contact Any type of unwanted completed sexual contact (not without force penetration) with the threat of nonphysical punishment, promise of reward, or pestering/verbal pressure. Sexual contact includes touching; grabbing or fondling of breasts, buttocks, or genitals, either under or over your clothes; kissing; licking or sucking; or some other form of unwanted sexual contact. Attempted sexual contact Unwanted attempted sexual contact (not penetration) with with force or threat of force force or threat of force. Sexual contact includes touching; grabbing or fondling of breasts, buttocks, or genitals, either under or over your clothes; kissing; licking or sucking; or some other form of unwanted sexual contact. SOURCE: Fisher, Cullen, and Turner (2000, Exhibit 2).

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SELECTED OTHER SURVEYS ON RAPE AND SEXUAL ASSAULT 83 Results Respondents in the study reported 123 incidents of rape or attempted rape, leading to the estimates of rape prevalence and incidents of female college students shown in Table 5-3. The prevalence rate for rape and at- tempted rape was 27.7 per 1,000 female students, and the incidence rate was 35.3 per 1,000 female students. It is important to point out that both of the rates are based on a reference period of approximately 7 months (aca- demic year) and are not an annual rate. The authors state that “projecting results beyond this reference period is problematic for a number of reasons, such as assuming that the risk of victimization is the same during summer months and remains stable over a person’s time in college” (Fisher, Cullen, and Turner, 2000, p. 10). However, it is likely that these rates would be higher than those published if they had accounted for an entire year rather than just 7 months. To better understand how these results compared with those collected through the NCVS, Fisher and Cullen (1999) worked with BJS to run a comparison study in the 1996-1997 academic year that was conducted close enough in time to the NCWSV and used a similar sample design so that the results could be compared to the NCWSV. The sample size for this study was 4,432 college women. This study was designed to mimic the NCWSV with the same sampling methodology, contact protocol, and interviewers except that the wording on the screen questions and incident reports were aligned to those used on the NCVS (tailored to a college population). Thus the NCWSV used behaviorally specific wording and the TABLE 5-3  Rape and Attempted Rape of Female College Students, NCWSV, 1996 Victims Incidents Rate per Rate per Number of 1,000 1,000 Type of Victims in Percentage Female Number of Female Victimization the Sample of Sample Students Incidents Students Completed rape  74 1.7 16.6 86 19.3 Attempted rape  49 1.1 11.0 71 16.0 Total 123 2.8 27.7* 157 35.3 *Total has been rounded. SOURCE: Fisher, Cullen, and Turner (2000, Exhibit 3, p. 11).

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84 ESTIMATING THE INCIDENCE OF RAPE AND SEXUAL ASSAULT 1.8 1.7 1.6 1.4 Percentage of Sample 1.2 1.1 Main Study 1.0 Comparison Study 0.8 0.6 0.4 0.31 0.16 0.18 0.2 0.07 0 Completed AƩempted Threat of Rape Rape Rape FIGURE 5-2 Comparisons of rape estimates between the National College Women Sexual Victimization Study main study and a comparison study. See text for discussion. Figure 5-2 SOURCE: Data from Fisher (2009, p. 142). BJS-sponsored comparison study did not.13 Figure 5-2 provides results from this comparison. In each category—completed rape, attempted rape, and threat of rape—the main study (featuring behaviorally specific wording) resulted in more reports of incidents than did the comparison study (using NCVS wording). There was the greatest difference between the two studies for rape, somewhat less of a difference for attempted rape, and considerably less difference for the threat of rape. See also Fisher (2009). NATIONAL INTIMATE PARTNER AND SEXUAL VIOLENCE SURVEY (2010) Fifteen years after the NVAWS, the CDC and NIJ again partnered to fund the NISVS, with additional support from the Department of Defense. 13  Fisher, Cullen, and Turner (2000, p.12) explain that answers in the comparison study “were not adjusted using verbatim responses [as is done with the NCVS]. We do not know how much this consideration affects the findings reported for the comparison component that is again, based on NCVS methodology.”

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SELECTED OTHER SURVEYS ON RAPE AND SEXUAL ASSAULT 85 It is a nationally representative survey that assesses experiences of sexual violence, stalking, and intimate partner physical violence, expressive aggres- sion, and control among English and Spanish-speaking women and men, aged 18 years of age and older. This study was first fielded in 2010, and the CDC intends to conduct it on an annual basis. The NISVS measures both 12-month and lifetime prevalence rates for the specified types of violence. This survey has a public health focus with concern that “unlike most other crimes, intimate partner violence or d ­ omestic violence is usually not a sudden, isolated, and unexpected inci- dent. It may involve years of emotional and psychological trauma as well as physical injuries, which may become increasingly more severe and occur frequently over time” (Office for Victims of Crime, n.d.). Methodology The data collection for the NISVS was conducted by RTI International for the CDC. Like the sample design for the NVAWS and the NCWSV, discussed above, the NISVS sample design uses RDD technology to reach the target population. Unlike the other two surveys, however, the sampling frame for this study includes both landline and cell phones. The first survey was conducted in 50 states and the District of Columbia ­ from January 22 through December 31, 2010. A total of 18,049 interviews were conducted (9,970 women and 8,079 men) targeting the U.S. non­ institutionalized population aged 18 years of age and older. This includes 16,507 completed and 1,542 partially completed interviews. A total of 9,086 females and 7,421 males completed the survey. Approximately 45.2 ­ percent of interviews were conducted from the landline telephone frame and 54.8 percent of interviews were conducted from the cell phone frame. Ad- vance letters were sent to approximately 50 percent of the landline sample addresses (obtained by using reverse address matching to the telephone numbers). The survey used only female interviewers. The overall weighted response rate in NISVS ranged from 27.5 to 33.6 percent.14 The cooperation rate was 81.3 percent. The NISVS 2010 Summary Report included estimates for five differ- ent categories of sexual victimizations including completed and attempted rape (see Box 5-1). Questions used to measure 12-month prevalence were unbounded by a previous survey or event. Respondents were first asked 14  This range in response rates reflects the differences in how the proportion of unknowns that might have been eligible but not interviewed is estimated, as applied in AAPOR response rate computation standards. These variations each handle “unknowns” (phone numbers that were never answered) differently. Assumptions are made based on respondents with known eligibility status for the survey.

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86 ESTIMATING THE INCIDENCE OF RAPE AND SEXUAL ASSAULT BOX 5-1 Sexual Violence Defined by the NISVS Five types of sexual violence were measured in NISVS. These include acts of rape (forced penetration), and types of sexual violence other than rape. Rape is defined as any completed or attempted unwanted vaginal (for women), oral, or anal penetration through the use of physical force (such as be- ing pinned or held down, or by the use of violence) or threats to physically harm and includes times when the victim was drunk, high, drugged, or passed out and unable to consent. Rape is separated into three types, completed forced pen- etration, attempted forced penetration, and completed alcohol or drug facilitated penetration. •  mong women, rape includes vaginal, oral, or anal penetration by a male A using his penis. It also includes vaginal or anal penetration by a male or female using their fingers or an object. •  mong men, rape includes oral or anal penetration by a male using his A penis. It also includes anal penetration by a male or female using their fingers or an object. Being made to penetrate someone else includes times when the victim was made to, or there was an attempt to make them, sexually penetrate someone without the victim’s consent because the victim was physically forced (such as being pinned or held down, or by the use of violence) or threatened with physical harm, or when the victim was drunk, high, drugged, or passed out and unable to consent. Sexual coercion is defined as unwanted sexual penetration that occurs after a person is pressured in a nonphysical way. In NISVS, sexual coercion refers to unwanted vaginal, oral, or anal sex after being pressured in ways that included being worn down by someone who repeatedly asked for sex or showed they were unhappy; feeling pressured by being lied to, being told promises that were untrue, having someone threaten to end a relationship or spread rumors; and pressure due to someone using their influence or authority. Unwanted sexual contact is defined as unwanted sexual experiences in- volving touch but not sexual penetration, such as being kissed in a sexual way, or having sexual body parts fondled or grabbed. Noncontact unwanted sexual experiences are those unwanted experi- ences that do not involve any touching or penetration, including someone ex- posing their sexual body parts, flashing, or masturbating in front of the victim, someone making a victim show his or her sexual body parts, someone making a victim look at or participate in sexual photos or movies, or someone harassing the victim in a public place in a way that made the victim feel unsafe. SOURCE: Black et al. (2011, p. 17).

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SELECTED OTHER SURVEYS ON RAPE AND SEXUAL ASSAULT 87 questions about lifetime prevalence (“How many people have ever . . .”). Respondents with an affirmative response were asked to provide “initials” to designate each offender, and follow-on questions were organized around each specific offender. In one of the follow-on questions, the respondent is asked whether the incident occurred within the past 12 months. Respon- dents were reminded of the date that was 12 months ago from the interview. Moving beyond the definition used in earlier studies, the definition of rape specifically included those victimizations that occurred when the victim was “drunk, high, drugged, or passed out and unable to consent.” It also measured sexual coercion by asking respondents if they experienced unwanted sexual penetration after being pressured in a nonphysical way. In addition, the survey included several items about unwanted sexual contact such as being made to penetrate someone else and several items about non- contact unwanted sexual experiences.15 Questions The specific screening questions on sexual violence victimization used in the NISVS asked about victimizations experienced in respondent’s life- time and during the previous 12 months (Black et al., 2011, p. 106): How many people have ever done any of the following things when you didn’t want it to happen? How many people have ever… • e  xposed their sexual body parts to you, flashed you, or masturbated in front of you? • m  ade you show your sexual body parts to them? Remem- ber, we are only asking about things that you didn’t want to happen. • m  ade you look at or participate in sexual photos or movies? • h  arassed you while you were in a public place in a way that made you feel unsafe? • k  issed you in a sexual way? Remember, we are only asking about things that you didn’t want to happen. • fondled or grabbed your sexual body parts? 15 These noncontact unwanted sexual experiences included such things as someone exposing their sexual body parts, flashing, or masturbating in front of the victim, someone making the victim show his or her body parts, someone making the victim look at or participate in sexual photos or movies, or someone harassing the victim in a public place or in a way that made the victim feel unsafe.

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88 ESTIMATING THE INCIDENCE OF RAPE AND SEXUAL ASSAULT When you were drunk, high, drugged, or passed out and un- able to consent, how many people ever . . . • h  ad vaginal sex with you? By vaginal sex, we mean that {if female: a man or boy put his penis in your vagina} {if male: a women or girl made you put your penis in her vagina}. • {  if male} made you perform anal sex, meaning that they made you put your penis into their anus? • m  ade you receive anal sex, meaning they put their penis into your anus? • m  ade you perform oral sex, meaning that they put their penis in your mouth or made you penetrate their vagina or anus with your mouth? • m  ade you receive oral sex, meaning that they put their mouth on your {if male: penis} {if female: vagina} or anus? How many people have ever used physical force or threats to physically harm you to make you . . . • have vaginal sex? • {if male} perform anal sex? • receive anal sex? • make you perform oral sex? • make you receive oral sex? • p  ut their fingers or an object in your {if female: vagina or} anus? How many people have ever used physical force or threats of physical harm to . . . • {  if male} try to make you have vaginal sex with them, but sex did not happen? • t  ry to have {if female: vaginal} oral, or anal sex with you, but sex did not happen? How many people have you had vaginal, oral, or anal sex with after they pressured you by . . . • d  oing things like telling you lies, making promises about the future they knew were untrue, threatening to end your relationship, or threatening to spread rumors about you? • w  earing you down by repeatedly asking for sex, or show- ing they were unhappy?

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SELECTED OTHER SURVEYS ON RAPE AND SEXUAL ASSAULT 89 • u  sing their authority over you, for example, your boss or your teacher? If a respondent replied affirmatively to any of the above questions, then he or she was asked to supply “initials” to designate the specific offender. Follow-on questions were structured around the individual offender and unwanted behavior. One follow-on question asked how many times this had happened in the past 12 months: • H  as [fill initials] [fill behavior] in the past twelve months, that is since [fill date 12 months ago]? Other follow-on questions were asked using similar question construc- tion. Examples: • W  as [fill initials] using alcohol, drugs or both the first time he/she [fill behavior]? • W  ere you using alcohol, drugs or both the first time [fill initials] [fill behavior]? Please remember that even if some- one uses alcohol or drugs, what happens to them is not their fault. • B  efore [fill initials] had [fill (vaginal, oral, anal)] sex with you when you were drunk, high, drugged, or passed out and unable to consent, do you think you were given alco- hol without your knowledge? Results The results of the NISVS 2010 were summarized in The National Inti- mate Partner and Sexual Violence Survey (NISVS): 2010 Summary Report (Black et al., 2011). The NISVS Summary Report did not provide incidence rates. It provided prevalence rates. Table 5-4 shows the survey’s 2010 prevalence estimates for completed forced penetration, attempted forced penetration, and alcohol- or drug-facilitated completed penetration—both 12-month and lifetime—by gender. Unfortunately, the 12-month prevalence estimates for rape victimizations for males did not meet the reliability crite- ria16 and were, therefore, not reported. The 12-month prevalence rates for all adults also were not published. 16  Statistical thresholds applied to all estimates in the 2010 Summary Report.

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TABLE 5-4  12-Month and Lifetime Prevalence of Rape Victimization, National Intimate Partner and Sexual 90 Violence Survey, 2010 12-Month Prevalence Lifetime Prevalence Weighted Percentage of Estimated Weighted Percentage of Estimated Type of Victimization U.S. Adult Women Number of Victimsa U.S. Adult Women and Men Number of Victims Women, 18+ Completed forced penetration 0.5 620,000 12.3 14,617,000 Attempted forced penetration 0.4 519,000 5.2 6,199,000 Completed alcohol/drug- 0.7 781,000 8.0 9,524,000 facilitated penetration Total completed, attempted, 1.1 1,270,000 18.3 21,840,000 and completed alcohol/drug- facilitated penetrationb Men, 18+ Completed forced penetration c c 0.9 970,000 Attempted forced penetration c c 0.4 499,000 Completed alcohol/drug- c c 0.6 685,000 facilitated penetration Total completed, attempted, c c 1.4 1,581,000 and completed alcohol/drug- facilitated penetrationb aRounded to nearest thousand. bRespondents who reported more than one subcategory are counted only once in the total estimate but are included in each relevant subcategory. For example, victims of completed forced penetration and alcohol- or drug-facilitated penetration are included in each of these subtypes of rape but are counted only once in the total estimate of rape prevalence. cEstimate not reported. The relative standard error of the estimate is greater than 30 percent, or the cell size is 20 or less.