Frequently Asked Questions
The following questions and answers are intended to anticipate interest in the “National Intimate Partner and Sexual Violence Survey—State Report” a report published in 2017 based on data from the 2010-2012 National Intimate Partner and Sexual Violence Survey.
What is this report about?
This report examines sexual violence, stalking, and intimate partner violence at the national and state level using 2010-2012 data from the National Intimate Partner and Sexual Violence Survey (NISVS). It describes the prevalence and characteristics of these forms of violence; the impact of violence experienced by an intimate partner; the prevalence of these forms of violence experienced as minors; and the health conditions associated with these forms of violence.
What is the most important thing people need to know about this report?
Sexual violence, stalking, and intimate partner violence remain significant public health issues, negatively impacting millions of women and men in the United States each year.
Why is this report important?
These data on sexual violence, stalking and intimate partner violence can provide a better understanding of these problems on a state-level and inform state efforts to prevent and respond to these problems. Understanding the magnitude, impact, and consequences of violence against women and men in the U.S. is an important first step in preventing violence. This information can be used to:
- Inform policies and programs that are aimed at preventing these forms of violence
- Establish priorities for preventing these forms of violence at the national, state, and local levels
Data collected in future years can also be used to examine trends in sexual violence, stalking, and intimate partner violence and to evaluate and track the effectiveness of prevention efforts.
This is the first report to offer this information at the state-level.
What are the key findings?
- The majority of victims first experienced sexual violence, stalking, or intimate partner violence prior to age 25.
- Women reported high rates of sexual violence, stalking, and intimate partner violence.
- High rates of sexual violence, stalking, and intimate partner violence victimization were reported by most racial and ethnic minority groups.
- Most sexual violence, stalking, and intimate partner violence victims knew their perpetrator.
- Women and men victims with a history of contact sexual violence (e.g., violence that includes some form of physical contact), stalking, or physical violence by an intimate partner were more likely to report 8 out of 10 health conditions examined (e.g., asthma, irritable bowel syndrome, poor physical health, and poor mental health) than those with no history of these forms of violence.
What should people do with this information?
This information can shed light on sexual violence, stalking, and intimate partner victimization experienced by male and female adults in the U.S on a state-level. State data can be used to inform and garner supports for state-specific prevention efforts as well as guide and evaluate progress at the state level toward the reduction of violence and adverse health conditions that are associated with victimization from violence.
Can a researcher access the survey instrument and raw survey data?
The 2010 NISVS data are available at no cost. This information is archived in the National Archive of Criminal Justice at ICPSR. On that site, you will find the 2010 codebook, survey instrument, and documentation regarding the data. The raw data are in a restricted access database, which have specific requirements for obtaining them. Consult the Access Notes for instructions on how to request access to the raw data.
What is the National Intimate Partner and Sexual Violence Survey?
NISVS is an ongoing, nationally representative survey that assesses sexual violence (SV), stalking, and intimate partner violence (IPV) among adult women and men in the U.S. The primary objectives of the survey are to describe:
- The prevalence and characteristics of sexual violence, stalking, and intimate partner violence
- Who is most likely to experience these forms of violence
- Patterns and impact of the violence experienced by specific perpetrators
- Health consequences of these forms of violence
CDC’s National Center for Injury Prevention and Control developed NISVS with the help of experts and stakeholders from various organizations and representatives from other federal agencies and launched it in 2010. NISVS includes data from English- and Spanish-speaking female and male adults living in the U.S. and asks respondents about victimization over their lifetime and in the 12 months prior to taking the survey.
The “National Intimate Partner and Sexual Violence Survey—State Report” uses aggregated NISVS data from 2010-2012 to capture national and state-level information on:
- Sexual violence (SV) victimization by any perpetrator, including rape (completed, attempted, and alcohol/drug facilitated forced penetration), being made to penetrate someone else, sexual coercion, unwanted sexual contact, and non-contact unwanted sexual experiences.
- Stalking victimization, including through the use of newer technologies such as text messages, emails, monitoring devices (e.g., cameras and GPS, or global positioning devices), by perpetrators known and unknown to the victim.
- Physical violence by an intimate partner, psychological aggression by an intimate partner, including information on expressive forms of aggression and coercive control, all forms of sexual violence as well as stalking and control of reproductive or sexual health by an intimate partner.
NISVS is a national random-digit-dial telephone survey. Respondents are randomly selected through both landline and cell phone numbers. For landline numbers, NISVS employs a list-assisted sampling approach to randomly select telephone numbers from the pool of available telephone numbers; for cellular telephone numbers, all active numbers have a chance to be randomly selected.
How was the survey funded?
Data collection was funded by the Centers for Disease Control and Prevention.
Will CDC issue a report like this every year?
CDC plans to issue reports on a recurring basis examining NISVS data.
Background and Methods
What was the survey methodology of NISVS?
NISVS is a national random digit dial (RDD) telephone survey of the non-institutionalized English and Spanish-speaking U.S. population aged 18 or older. NISVS uses a dual-frame sampling strategy that includes both landline and cell phones. NISVS makes use of the latest U.S. telephone user and usage information. This dual-frame sampling strategy is used in other RDD telephone surveys conducted by the CDC and by other government agencies. The survey was conducted in all 50 states and the District of Columbia.
What was the overall response rate to the survey of NISVS?
The overall weighted response rates across three years ranged from 27.5% to 33.6% and cooperation rates ranged from 80.3% to 83.5%. The cooperation rate reflects the proportion of adults who agreed to participate among those who were contacted and determined to be eligible. In short, once contact was made and eligibility determined, the majority of respondents chose to participate in the survey.
Interpreting NISVS Results
How should state estimates be interpreted?
The tables include a prevalence estimate, the estimated number of victims, and 95% confidence intervals. It is important to keep in mind that the prevalence estimates are based on a sample and not a census of the U.S. population. Estimates that are based on a sample always include some error. This uncertainty or error is estimated with a 95% confidence interval. The confidence interval provides a range of values that likely include the true prevalence estimate. The 95% confidence interval means that we can be 95% confident that the true prevalence is within the interval.
Readers are strongly cautioned against comparing estimates across states or by sex. Estimates that have overlapping confidence intervals might not be meaningfully different from each other and additional statistical analyses are needed to test for differences. Some confidence intervals are relatively large because the estimate is based on a small number of people who reported the particular type of victimization in the sample. Across all the tables, very few states have confidence intervals that do not overlap with those for the highest estimate in the table and even fewer have confidence intervals that do not overlap with the estimate for the entire U.S. population. Similarly, when data are available for men and women the confidence intervals tend to overlap and when they do not overlap the estimates are often higher for women.
The confidence intervals will become smaller as additional years of data become available and can be aggregated across years. We also expect to be able to use the data from additional years to provide rolling 12 month prevalence estimates for states.
Why are the reported rates higher in some states than others?
When reviewing state-level data, it is important to recognize that differences between states should not be interpreted as deficiencies. Compared to national data, state-level prevalence estimates are more vulnerable to imprecision due to small sample sizes. In addition, there are many factors (known and unknown) that may influence prevalence. Known examples include differences in population demographics (e.g., age distribution, social determinants), external stressors (e.g., economic downturn, job loss, poverty), and potential cultural differences in reporting and/or beliefs within sub-populations. Most of our state estimates are lifetime estimates and the violence could have been experienced outside of the state. The estimates represent the residence of the participants/victims at the time of the survey. Data could be helpful in planning for resources for victims.
Do states with a lower lifetime prevalence of sexual violence, intimate partner violence, or stalking have better state policies or laws?
We cannot assume that states with lower lifetime prevalence estimates have better state policies or laws. An evaluation would have to be conducted to determine the impact of state policies or laws. Research evaluating state-level policies or other state-level interventions can be conducted when additional years of NISVS data are collected. It is important to remember that the survey captures the state where the respondent is currently living. That may or may not be the state where the violence occurred.
CDC recently developed technical packages, which outlines strategies, including policies, with the strongest evidence base to prevent sexual violence [PDF 2.85MB] and intimate partner violence [PDF 4.52MB]. Research evaluating the impact of these policies could be conducted.
Why is CDC releasing 2012 data on sexual violence when DOJ has recently released 2015 data?
The most recent NISVS data that we have available is from 2012. In order to provide the most reliable estimates for states, we decided to merge data across prior years. This is the first time we’ve been able to provide such comprehensive state estimates. State data is not available from DOJ’s National Crime Victimization Survey (NCVS). NISVS data from 2015 will be released in 2017.
What do these data say about the IPV gender symmetry/asymmetry debate?
NISVS data suggest that while both men and women experience IPV, women are burdened significantly heavier in multiple forms of lifetime intimate partner perpetrated violence (rape, sexual coercion, stalking, physical violence, and the composite measure of any contact sexual violence, physical violence, and/or stalking). In addition, female victims of contact sexual violence, physical violence, and/or stalking by an intimate partner experience significantly greater lifetime and past 12-month IPV-related impacts (any reported IPV-related impact, fearful, concerned for safety, any PTSD symptoms, injury, needed medical care, needed housing services, needed legal services, and missed at least one day of work/school) than that of male victims.
What is “made to penetrate” and how is it different from rape? Shouldn’t they be counted together?
Given that the made to penetrate (MTP) category has not previously been addressed in the sexual violence literature, there is much work yet to be done to understand the experiences of victims. The difference between rape and being made to penetrate is that in the definition of rape the victim is penetrated; “made to penetrate” by definition refers to cases where the victim penetrated someone else. CDC treats these two types of sexual violence as distinct constructs to better understand the specific experiences of victims of sexual violence. CDC believes that this level of specificity is helpful for raising awareness about both rape and MTP.
MTP includes times when the victim was made to, or there was an attempt to make them, sexually penetrate someone else without the victims 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.
We encourage additional work to better understand the nature and consequences of both types of sexual violence to help guide prevention activities and to increase awareness about the needs of victims. To this end, in some of our reports we combine the touch types of SV into a Contact SV category (includes both rape and MTP, sexual coercion, and unwanted sexual contact), and we are exploring also combining the forced penetration types of SV, which would combine MTP and rape.
Implications of Findings
What implications do these data have for prevention efforts and services?
This report provides the national and state-specific prevalence estimates of sexual violence, stalking and intimate partner violence of adults and their association with numerous health conditions. Given the burden of these forms of violence in the lives of women and men in the U.S., including experiences occurring in childhood, it is important to focus on prevention and identify evidence-based strategies and approaches that reduce the likelihood of violence.
Comprehensive strategies to prevent these types of violence requires that state public health departments partner with other sectors, such as education, justice, and social services, to implement prevention efforts. Prevention strategies should also address the aftermath of violence to make sure that appropriate services and supports are in place for victims to ensure healing and prevent further victimization.
To help states and communities take advantage of the best available evidence to prevent violence, CDC released technical packages that describe strategies, specific approaches, and the evidence of their effectiveness. The technical packages focus on preventing sexual violence, child abuse and neglect, suicide, youth violence, and intimate partner violence (see www.cdc.gov/violenceprevention/pub/technical-packages.html). The prevention strategies and approaches discussed in this report come from these technical packages.
What implications do these data have for future research?
We know more now about what it takes to prevent sexual violence, stalking, and intimate partner violence, but additional research is needed to add to the evidence base of what works to prevent these problems. Applying evidence-based strategies and approaches that address multiple forms of violence has the most promise. It is also important to address the capacity to implement such strategies in a sustainable way. A successful strategy to prevent sexual violence, stalking, and intimate partner violence will need to be one that is comprehensive, cross-cutting, data driven, and involves multiple sectors working together.
Limitations of this Report
What are the limitations of the NISVS methodology?
As with all surveys, NISVS is likely to be an underestimate of the true burden of these forms of violence because it does not capture all possible forms of SV, stalking, and IPV, and some people, who may currently be experiencing severe forms of violence, may not be comfortable sharing their experiences.
There are limitations to the state-level data presented in the report. Pooling three years of data allowed the presentation of some new, previously unreported estimates, but there are still a number of state-level estimates that could not be produced because of lack statistical significance. The ability of NISVS to capture three years worth of data at the state-level is limited by the sample size of each year’s survey and the particular questions it contains.
Additionally, NISVS relies on self-report of prior experiences and recall bias may impact the accuracy of reporting, especially when recalling events that occurred in the distant past (such as sexual violence, stalking, or intimate partner violence that occurred as a minor), or when recalling the specific details related to the event (e.g., age of occurrence, impact of the event).