Epidemiology and prevention of violence, including homicide, suicide, sexual assault, child abuse, battering, & firearms
Violence against women as a public health issue
Firearms as a consumer product
Professor Susan B. Sorenson has a unique interdisciplinary background in epidemiology, sociology, and psychology. Professor of Social Policy, Professor of Health & Societies, and Senior Fellow in Public health, she moved to Penn in 2006 after more than 20 years at the UCLA School of Public Health. Dr. Sorenson is the Faculty Director of the Ortner Center on Violence & Abuse, an interdisciplinary center that involves nine of Penn’s twelve schools.
Since 1986, Professor Sorenson has taught a graduate course in family and sexual violence – the first violence prevention course in a school of public health in the nation. She currently teaches three courses that she developed: Violence in Relationships (graduate); Public Health and Violence (undergrad); and Foundations of Public Health (undergrad).
With over 150 publications to her credit, Professor Sorenson has published widely in the epidemiology and prevention of violence, including the areas of homicide, suicide, sexual assault, child abuse, battering, and firearms. She helped establish violence against women as a public health issue and furthered the study of firearms as a consumer product. A primary focus of her work is the social context in which violence occurs, specifically, the norms that shape whether and how violence is tolerated.
In addition to her academic work, Dr. Sorenson has served on the board of directors and advisory boards of local community-based organizations, state government agencies, and university injury prevention centers. In 1991, she co-founded the Violence Prevention Coalition of Greater Los Angeles, a broad coalition of agencies and individuals which continues to this day. She has provided invited testimony on violence prevention at the local, state, and federal levels.
Professor Sorenson has served in multiple advisory roles. She was a member of the National Academy of Science’s Panel on Research on Violence Against Women, a consultant to President Clinton’s National Advisory Council on Violence Against Women, a consultant to UNICEF’s May 2000 report on Domestic Violence Against Women and Girls, a member of the advisory panel for the 2001 U.S. Surgeon General’s Report on Youth Violence, author of a 2008 WHO report on health indicators of violence against children in low- and middle-income countries, and a member of the 2013 Institute of Medicine committee on Priorities for a Public Health Research Agenda to Reduce the Threat of Firearm-related Violence. She currently is serving a second term on the Committee on Law and Justice for the National Academy of Sciences.
Professor Sorenson’s contributions to science include framing violence against women as a public health issue, studying firearms as a consumer product, and applying multiple and emerging research methods to the study of the epidemiology and prevention of violence. Policy implications are a core aspect of her research. Listed below are some of her publications from the past five years. For a copy of any of these articles or others by Professor Sorenson, please see Scholarly Commons or contact Professor Sorenson.
Knowing a sexual assault victim or perpetrator: A stratified random sample of undergraduates at one university
Sorenson SB, Joshi M, Sivitz E. Knowing a sexual assault victim or perpetrator: A stratified random sample of undergraduates at one university. Journal of Interpersonal Violence, 2014; 29:394-416.
In a stratified random sample of 2,400 undergraduates, nearly two thirds (64.5%) reported that they know one or more women who were a victim of any one of eight types of sexual assault, and over half (52.4%) reported that they know one or more men who perpetrated any of the types of sexual assault. Most students reported knowing victims and perpetrators of multiple types of assault. Students’ preexisting personal knowledge should be included in assessments of program effectiveness and, ideally, in program design.
“Do you know what it feels like to drown?”: Strangulation as coercive control in intimate relationships
Thomas KA, Joshi M, Sorenson SB. “Do you know what it feels like to drown?”: Strangulation as coercive control in intimate relationships. Psychology of Women Quarterly, 2014; 38, 124-137.
We extended prior work by using grounded theory in a qualitative study to explore women’s experiences of, thoughts about, and reactions to being strangled. Each of the 17 domestic violence shelter residents had been strangled at least once by an intimate partner; most had survived multiple strangulations. Despite other severe abuse and a high level of fear, all were shocked that their partner strangled them. Participants reported an intense sense of vulnerability when they recognized during the assault how easily they could be killed by their partner. Nonetheless, they seemed to think of strangulation, not as a failed murder attempt, but as a way to exert power.
Self-presentation on the web: Agencies serving abused and assaulted women
Sorenson SB, Shi R, Zhang J, Xue J. Self-presentation on the web: Agencies serving abused and assaulted women. American Journal of Public Health, 2014; 104: 702–707.
In a 10% systematic sample of 3774 agencies listed in two national directories, we examined the content and usability of the websites of agencies serving women victims of violence. The service and marketing functions were met fairly well by the agency home pages, but usability (particularly readability and offer of a mobile version) and efforts to increase user safety could be improved. The one third of agencies that lack a website will not reach the substantial portion of the population that uses the Internet to find health information and other resources.
A systematic review of the epidemiology of nonfatal strangulation, a human rights and health concern
Sorenson SB, Joshi M, Sivitz E. A systematic review of the epidemiology of nonfatal strangulation, a human rights and health concern. American Journal of Public Health, 2014; 104: e54–e61.
Few specific acts of nonfatal abuse are associated with as wide of a range of health problems or are as difficult to detect as strangulation. In the first systematic review of the epidemiology of strangulation, we identified 23 articles based on 11 surveys of 75,875 individuals in 9 countries in 4 regions of the world. Women are more likely than men to report that they were strangled by an intimate partner. Strangulation does not require access to a particular weapon, and its use is not restricted to a specific geographic region. A focus on specific acts, such as strangulation and acid burnings, as well as parallels to other rights violations (e.g., water boarding) may help convey to policymakers and others the risk to and terror experienced by those being abused.
Assessing views about gun violence reduction policy: A look at type of violence and expected effectiveness
Sorenson SB. Assessing views about gun violence reduction policy: A look at type of violence and expected effectiveness. Preventive Medicine, 2015, 79: 50-54.
We examined the content and usability of the websites in a systematic 10% sample of 3774 agencies serving women victims of violence. The service and marketing functions were met fairly well by the agency home pages, but usability (particularly readability and offer of a mobile version) and efforts to increase user safety could be improved. The one third of agencies that lack a website will not reach the substantial portion of the population that uses the Internet to find health information and other resources.
Forecasting domestic violence: A machine learning approach to help inform arraignment decisions
Berk RA, Sorenson SB, Barnes G. Forecasting domestic violence: A machine learning approach to help inform arraignment decisions. Journal of Empirical Legal Studies, 2016; 13: 94-115.
Arguably the most important decision at an arraignment is whether to release an offender until the date of his or her next scheduled court appearance. Using 28,000 arraignment cases from a major metropolitan area in which an offender faces domestic violence charges, one of three possible post-arraignment outcomes was forecasted to occur within two years: (1) a domestic violence arrest associated with a physical injury, (2) a domestic violence arrest not associated with a physical injury, and (3) no arrests for domestic violence. We incorporated asymmetric costs for different kinds of forecasting errors so that very strong statistical evidence is required before an offender is forecasted to be a good risk. Using the decision tool, the number of re-arrests for domestic violence could be cut in half.
“Consent is Good, Joyous, Sexy”: A banner campaign to market consent to college students
Thomas KA, Sorenson SB, Joshi M. “Consent is Good, Joyous, Sexy”: A banner campaign to market consent to college students. Journal of American College Health, 2016; 64(8): 639-650.
One responsibility of U.S. colleges is to prevent rape and sexual assault of and by students. In fact, federal law mandates, among other things, that colleges and universities receiving federal funding offer sexual assault prevention programs. Using an experimental design embedded in an online survey following a campus exhibit, we found that colorful banners with pithy, upbeat messages hold promise for engaging undergraduates in conversations and proactive activities related to sexual assault prevention.
Guns in intimate partner violence: Comparing incidents that involve a gun, other weapon, or no weapon
Sorenson SB. Guns in intimate partner violence: Comparing incidents that involve a gun, other weapon, or no weapon. Journal of Women’s Health, 2017; 26(3):249-258.
In this study of 35,413 intimate partner calls for assistance, 1% involved a gun. A gun was used most often (about two-thirds of the time) to threaten the partner; in 15% of the gun cases, the offender pistol whipped, shot at, or shot the victim. The use of a gun was associated with more violent behaviors by the abuser and more negative outcomes for the victim. The violent behaviors and negative outcomes are, generally speaking, even worse when another type of weapon is used. Guns heighten fear and compliance, which likely reduces willingness to end the relationship, thus, promoting chronic abuse. Documentation of officer compliance with state law could be improved.
Violence against women and household ownership of radios, computers, and phones in 20 countries
Cardoso L, Sorenson SB. Violence against women and household ownership of radios, computers, and phones in 20 countries. American Journal of Public Health, 2017; 107(7):1175–1181.
Sometimes the private sector creates unintended consequences. We investigated the possibility of one with global consequences – the proliferation of information and communication technology.
Cross-sectional data collected in 20 low- and middle-income countries that participated in UNICEF’s Multiple Indicator Cluster Surveys during 2006 through 2014, assess the association between such technologies and justifications for wife beating. The 133,843 women participants were asked whether a husband is justified in beating his wife under five circumstances: if she goes out without telling him, neglects the children, argues with him, refuses to have sex, or burns the food.
Household ownership of a radio, computer, fixed phone, or mobile phone was associated with a higher likelihood of rejecting wife-beating; the largest effect was having a computer. These findings were not related to finances – independent of both country development and household wealth, the more such technologies, the more likely women were to reject justifications for wife-beating.
New data on intimate partner violence and intimate relationships: Implications for gun laws and federal data collection
Sorenson SB, Spear D. New data on intimate partner violence and intimate relationships: Implications for gun laws and federal data collection. Preventive Medicine, 2018;107:103-108.
Age at first marriage has risen substantially and birth rates are at a record low; people are spending more time in relationships that, by comparison, have fewer emotional, financial, and legal commitments. Little research has examined intimate partner violence (IPV) prevalence in current and former adult (vs. adolescent) dating relationships. Such information is relevant to federal firearms policies that are based on the nature of an intimate relationship. We examined assaultive behaviors by the type and status of the relationship – current spouse, former spouse, current boyfriend or girlfriend, and former boyfriend or girlfriend – in 31,206 IPV incidents responded to by Philadelphia police in 2013. Over 80% of the IPV incidents involved individuals in non-marital relationships. Incidents involving current boyfriends or girlfriends had the highest percentage of violent behaviors (e.g., punch, strangle). They also were more likely than current spouses to use bodily weapons (hands, fists, or feet) or non-gun weapons (knives, bats, etc.) (AOR=1.19 and 1.43, respectively), to injure their victims (AOR=1.37), and to be arrested (AOR=1.46). Former unmarried partners had the highest odds of stalking their intimate (AOR=3.37) and violating a restraining order (AOR=2.61). Gun use was similar across relationship type. A growing portion of the population is not protected by federal policies designed to keep guns out of the hands of abusers. Current boyfriends and girlfriends are a risk to their intimates. Federal data collection practices and firearm policies merit updating to more fully take into account dating, same-sex marriage,and other partnerships. (journal abstract)
Non-fatal gun use in intimate partner violence: A systematic review of the literature
Sorenson SB, Schut R. Non-fatal gun use in intimate partner violence: A systematic review of the literature. Trauma, Violence, & Abuse, 2018;19(4):431-442
This paper presents the first systematic review of a topic that has received relatively little attention from researchers interested in violence against women: the prevalence of intimate partners’ non-fatal use of guns. The available information indicates that the number of U.S. women alive today who have had an intimate partner use a gun against them is substantial: About 4.5 million have had an intimate partner threaten them with a gun and nearly one million have been shot or shot at by an intimate partner. Implications for policy, practice, and research are discussed, all of which include expanding an implicit focus on homicide to include an intimate partner’s non-fatal use of a gun.
Differences between new and long-standing gun owners
Wertz J, Azrael D, Hemenway D, Sorenson SB, Miller M. Differences between new and long-standing gun owners: Results from a nationally-representative survey. American Journal of Public Health, 2018;108(7):871-877.
Gun ownership is dynamic and, in this study, we found that about one million U.S. residents become new gun owners each year. We performed a cross-sectional analysis of a 2015 nationally-representative probability-based online survey. We defined new gun owners as current firearm owners who acquired all of their firearms within the past 5 years, but who lived in a home without a gun at some time over the past 5 years. We defined long-standing firearm owners as all other current gun owners. New gun owners represented 10% of all current US adult gun owners. In addition to being younger than long-standing gun owners, new gun owners were more likely to be liberal, own fewer guns, own handguns, own guns only for protection, and store guns in a safe manner.
Recent and emerging technologies: Implications for women’s safety
Cardoso LF, Sorenson SB, Webb O, Landers S. Recent and emerging technologies: Implications for women’s safety. Technology in Society, January 2019, in press, posted online January 2019.
New technologies have multiple implications for women’s safety and well-being. As emerging scholarship begins to capture the scope and psychosocial impact of technology-related violence, the literature can become outpaced by the rapid development of technologies, some of which are designed to protect women. This exploratory study conducted a series of online searches to document and describe new technologies that can be used to enhance or reduce women’s safety. A total 23,100 web-based articles, including but not limited to news stories and marketing materials, were identified and screened; 495 were reviewed and key constructs were coded. Two thirds of the articles addressed how technology could protect women and over half addressed perpetration; 18.8% addressed both. Protection focused largely on two technologies –mobile telephones (37.2%) and wearable devices (19.4%) – and sexual or physical assault (57.2%). Perpetration focused on mobile telephones (58.4%) and e-mail (43.9%) and cyber- or in-person stalking (63.2%). Women are advised to alter their online behavior; negligible attention is given to tech companies’ responsibilities. Of the 98 products identified, most (80.2%) – typically a wearable device or app – were described as protecting women from sexual or physical assault. The products are marketed, with little evidence, as a way for women to protect themselves from assault. The introduction of corporate messaging and profit into the long-standing issue of violence against women is changing the means by which women can be abused and simultaneously and perhaps inadvertently is reinforcing norms that hold women accountable for their victimization. (journal abstract)
After the gun: Examining police visits and intimate partner violence following incidents involving a firearm
Small D, Sorenson SB, Berk RA. After the gun: Examining police visits and intimate partner violence following incidents involving a firearm. Journal of Behavioral Medicine, January 2019, in press.
Laws have been enacted to keep firearms out of the hands of abusers. In this study, we examined one such effort – removal of a firearm at the scene of intimate partner violence (IPV) – to assess the subsequent occurrence and number of IPV incidents responded to by police and subsequent risk of injury to the victim. Using the 28,977 IPV calls in one large U.S. city to which officers responded during the 2013 calendar year, we identified 220 first-time incidents in which offenders used (i.e., brandished, pistol whipped, shot) a pistol, revolver, rifle, or shotgun. Officers reported removing a firearm from 52 (24%) of the offenders. After using full propensity score matching to control for potential confounders, logistic and Poisson regressions were used to assess differences between those from whom a firearm was removed and those whose firearm was not removed. Firearm removal at the scene of an IPV incident appears to increase the likelihood of subsequent IPV reports to police and suggestive evidence that subsequent injury to the victim might increase as well. The offender shifting from threats with a firearm to physical violence and a change (an increase as well as a decrease) in victim willingness to summon police may account for the findings. (journal abstract)