Sexual Experiences Survey

The Sexual Experiences Survey (SES) measures unwanted sexual experiences that include rape. It pioneered a self-report, multi-item, behaviorally specific approach to measuring sexual victimization and [Page 661]perpetration. A typical SES item is as follows: “Someone put his penis, or fingers, or objects (such as a bottle or a candle) into my vagina after I had been drinking alcohol or using drugs and was conscious but too drunk or out of it to consent or stop what was happening.” This wording describes the legal elements of rape, but avoids terms like being raped or raping someone. The latter are not only legal technical terms, but also they also require a willingness to take up stigmatized identities that people generally avoid. Behaviorally specific questioning is now standard and has informed measurement of the most recent national studies of sexual violence.

Brownmiller's 1971 book, Against Our Wills: Men, Women, and Rape, hypothesized far more rapes than police reports document. The SES was developed to test her assertion. The first study reporting results from the SES appeared in 1982 and focused on one university campus; it was followed 5 years later by a 32-campus national study. The latter revealed that approximately 1 in 4 college women responded affirmatively to one or more rape or attempted rape items and 1 in 13 college men reported perpetrating such acts. These numbers have been equaled or exceeded many times by other investigators in community, higher education, and military settings. Today the SES fulfills varied roles in academic studies: to obtain incidence and prevalence data, to identify potential risk and vulnerability factors, to select groups who have perpetrated or been victimized for further study, to validate standard assessments that are hypothesized to predict sexual victimization or perpetration, and as outcome measures for prevention or therapeutic interventions intended to lower rates of sexual violence. Self-report surveys were shown in a 2005 meta-analysis of over 19,000 sex offenders to be as effective at detecting reoffending as searching national police databases.

SES-generated data were part of the rationale for the first Violence Against Women Act, which triggered scrutiny of its scientific merits. The SES has proved robust in replicability, psychometric reliability, and transportability to diverse cultural groups and languages. The items were generally rated by prosecutors as successful in mapping onto legal definitions of sexual offenses. Interviews with community members suggest that investigators and respondents bring similar interpretations to the language of most items. However, valid criticisms have emerged that led a collaborative group to produce draft revisions of the SES in 2004. Among the issues the collaborative group revisited was removing the heterosexist bias, where women were asked about victimization only by men, and men weren't asked about victimization at all. Additionally, the questioning about alcohol needed more clarity so that an act labeled rape involved not just drinking or drug use, but impairment and inability to consent. Other fixes included updating language, making oral sex items more behaviorally specific, clarifying attempted rape, and measuring gang rape. Although the psychometrics for the revised versions are not yet available, the Centers for Disease Control and Prevention included both the victimization and perpetration version of the original SES in their 2005 compendium of recommended measures for sexual violence.

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