Kathleen C. Basile, 1,2 Ileana Arias, 1 Sujata Desai, 1 and Martie P. Thompson 1

Transcription

1 Journal of Traumatic Stress, Vol. 17, No. 5, October 2004, pp ( C 2004) The Differential Association of Intimate Partner Physical, Sexual, Psychological, and Stalking Violence and Posttraumatic Stress Symptoms in a Nationally Representative Sample of Women Kathleen C. Basile, 1,2 Ileana Arias, 1 Sujata Desai, 1 and Martie P. Thompson 1 This study examines whether experiences with four different types of intimate partner violence (IPV) increase risk for posttraumatic stress disorder (PTSD) symptoms. We examined impacts of physical, sexual, psychological, and stalking victimization by a current partner on PTSD symptoms, the extent to which each type of IPV accounted for significant variance in PTSD symptoms when controlling for other forms, and the increase in PTSD symptoms from multiple forms of IPV. Findings reveal that all types of violence were associated with increased PTSD symptoms. When controlling for other types of violence, physical, psychological, and stalking violence were still associated with PTSD symptoms. There was evidence of a dose response in which the more types of violence experienced, the more PTSD symptoms. KEY WORDS: intimate partner violence; physical violence; sexual violence; psychological violence; stalking; posttraumatic stress disorder symptoms; nationally representative sample of women. Intimate partner violence (IPV), defined here as the use of actual or threatened physical, sexual, psychological, or stalking violence, by current or former partners (including same or opposite sex), is a significant public health problem in the United States. The National Violence Against Women Survey (Tjaden & Thoennes, 2000a), sponsored by the National Institute of Justice (NIJ) and the Centers for Disease Control and Prevention (CDC) indicated that approximately 1.5 million women and 834,700 men are physically assaulted or raped by intimate partners in the United States annually. Women who are physically assaulted by an intimate partner experience an average of 3.4 separate assaults per year and those who are raped experience 1.6 rapes annually on average. In 1 Centers for Disease Control and Prevention, Atlanta, Georgia. 2 To whom correspondence should be addressed at Division of Violence Prevention, Centers for Disease Control and Prevention, Mailstop K60, 4770 Buford Highway, Atlanta, Georgia ; kbasile@cdc.gov. addition, 503,485 women and 185,496 men are stalked annually by an intimate partner. Although both men and women report IPV victimization, IPV victimization is more prevalent and frequent among women than men and differences between women s and men s rates of victimization become greater as the severity of assault increases (Stets & Straus, 1990). Female victims of IPV are significantly more likely than men to sustain an injury, receive medical care, be hospitalized, receive counseling, and lose time from work (Tjaden & Thoennes, 2000b). Relative to men, women are more likely to be injured if they are victimized by an intimate partner than if they are assaulted by a nonintimate (Bachman & Saltzman, 1995), and are 13 times more likely to suffer an injury from IPV than from an accident (Stark, Flitcraft, & Frazier, 1979). Injuries resulting from IPV victimization can include bruises, scratches, burns, broken bones, miscarriages, and knife and gunshot wounds (Crowell & Burgess, 1996). In addition to physical injuries, women victims of physical IPV /04/ /1 C 2004 Springer Science+Business Media, Inc.

2 414 Basile, Arias, Desai, and Thompson experience adverse physical health consequences such as chronic pain disorders and gastrointestinal disorders (Coker, Smith, Bethea, King, & McKeown, 2000; Crowell & Burgess, 1996; Tjaden & Thoennes, 2000b), as well as adverse psychological consequences such as depression, suicidal behavior, substance abuse, and low self-esteem (Resnick, Kilpatrick, Dansky, Saunders, & Best, 1993; Ruback & Thompson, 2001). Plichta and Falik (2001) found similar physical and psychological consequences among women who had experienced sexual IPV. Among their sample of wife rape victims, Finkelhor and Yllo (1985) found that the women were unable to trust men, had an aversion to intimacy and sex, and feared repeat assault. Sexual IPV has also been associated with sexually transmitted disease infection (Molina & Basinait- Smith, 1998). Psychological IPV has been associated also with a range of physical and psychological consequences (Aguilar & Nightingale, 1994; Kahn, Welch, & Zillmer, 1993; Marshall, 1996). As early as the mid-eighties, Walker (1984) suggested that the range of psychological symptoms frequently experienced by victims of IPV overlapped significantly with those that comprise diagnostic criteria for posttraumatic stress disorder (PTSD). More recent empirical data suggest that female victims of physical, sexual, psychological, and stalking IPV are at particular risk for PTSD (Arias & Pape, 1999; Mechanic, Uhlmansiefk, Weaver, & Resick, 2000; Vitanza, Vogel, & Marshall, 1995). For example, Mechanic et al. (2000) found that women who were what the authors called relentlessly stalked by intimate partners (defined as reporting at least six different types of stalking events that each occurred once a week or more frequently) had higher rates of depression and PTSD than women who were less frequently stalked. Among battered women, estimates of the prevalence of PTSD range from 33% (Astin, Lawrence, & Foy, 1993; Cascardi, O Leary, Lawrence, & Schlee, 1995) to 84% (Kemp, Rawlings, & Green, 1991), depending on the population sampled, the method of assessment of PTSD, and time since the last IPV event. Mertin and Mohr (2001) reported that 42% of their sample of battered women s shelter residents met DSM-IV (American Psychiatric Association, 1994) diagnostic criteria for PTSD when they entered the shelter while 14% continued to meet criteria for the disorder 12 months later. Similarly, Rothbaum, Foa, Riggs, Murdock, and Walsh (1992) found that 50% of rape victims met PTSD diagnostic criteria 3 months after the rape, and 90% of rape victims met diagnostic criteria for PTSD within 2 weeks of the rape with the exception of the duration criterion (criterion E). The conceptualization of IPV victims psychological reactions as PTSD has been noted as problematic (Crowell & Burgess, 1996). The diagnostic criteria for PTSD were designed to reflect dysfunctional reactions to single traumatic events and may not capture reactions to repeated or chronic traumatization such as intimate partner physical or psychological victimization and stalking as completely (Herman, 1992). PTSD does not account for all the psychological symptoms exhibited by victims of IPV such as depression and other anxiety disorder symptoms. However, these symptoms frequently co-occur with those of PTSD (Brown, Campbell, Lehman, Grisham, & Mancill, 2001) and between 79% and 88% of individuals with PTSD have been found to meet criteria for at least one other psychiatric diagnosis (Kessler, Sonnega, Bromet, Hughes, & Nelson, 1995). Additionally, victims of IPV may exhibit most but not all of the symptoms of PTSD. For example, victims of IPV may report nightmares, heightened arousal, and poor concentration but little or no avoidance of trauma-related events such as the home or abusive intimate partner. Accordingly, PTSD symptoms may be more relevant among IPV victims than full PTSD. Although not meeting all criteria for a diagnosis of PTSD, partial or subthreshold PTSD may lead to as much impairment as full PTSD. Definitions of subthreshold PTSD vary. Stein, Walker, Hazen, and Forde (1997) used a conservative definition (i.e., meeting DSM-IV criteria except missing one or two of the required criterion C symptoms and/or missing one of the two required criterion D symptoms) and found that 53% of those who met criteria for subthreshold PTSD sought services for their symptoms compared to 60% of individuals who met full PTSD criteria. Studies that have examined the relationship between IPV victimization and PTSD have relied primarily on clinical samples of women such as those residing in battered women s shelters or those contacting outpatient physical and mental health clinics for services. Clinical and convenience samples limit our ability to generalize findings to the general population. Population-based studies enable us to identify accurate rates of victimization and risk and protective factors and consequences. Studies that examine the relationship between PTSD and IPV have focused on single forms of IPV. Physical, sexual, psychological, and stalking IPV victimization often co-occur. Follingstad, Rutledge, Berg, Hause, and Polek (1990) found that among a sample of 234 women with a history of battering only three reported never experiencing psychological abuse. Finkelhor and Yllo (1985) found that 48% of the 50 women in their qualitative sample were classified as experiencing battering rapes, or rape in the context of a physically violent marriage. Other researchers

3 Violence and Posttraumatic Stress Symptoms 415 examining rape in marriage have reported similar findings on sexual and physical IPV co-occurring (Basile, 1999; Bergen, 1996; Frieze, 1983; Pagelow, 1992; Peacock, 1998; Russell, 1990). Mechanic et al. s (2000) sample of women who were relentlessly stalked by intimate partners was also physically, sexually, and emotionally abused by the same partners. In order to determine the relationship between any form of IPV and PTSD, other forms of victimization need to be accounted for or controlled. Arias and Pape (1999) found that physical violence was not related to PTSD symptomatology among women residing in a battered women s shelter when their experiences of psychological victimization were statistically controlled. Additionally, the impact of multiple forms of victimization co-occurring on the risk for PTSD has not been determined. The purpose of this study was to identify the extent to which experiences with IPV victimization were related to PTSD symptoms using a nationally representative sample of women. We specifically assessed variation in PTSD as a function of physical, sexual, psychological, and stalking victimization experiences by a current partner. We were additionally interested in the extent to which each type of IPV accounted for significant variance in PTSD symptomatology when controlling for other co-occurring forms of IPV, and the increase in risk for PTSD symptoms as a function of experiencing multiple forms of IPV victimization. Based on findings in previous research (Arias & Pape, 1999; Follingstad et al., 1990; Mechanic et al., 2000; Vitanza et al., 1995), we hypothesized that (1) physical, sexual, psychological, and stalking IPV would be significantly associated with PTSD symptoms both separately and (2) in combination; and (3) the more IPV victimization experienced by a woman, the higher the levels of PTSD symptoms. Method Sample and Procedures Data for this study come from the National Violence Against Women Survey (NVAWS), a survey of women s and men s personal safety that was funded by the National Institute of Justice and the Centers for Disease Control and Prevention. Data were collected during the period of November 1995 to May 1996 from 8,000 women and 8,000 men. The NVAWS was a random digit dial survey of households with telephones in the United States. Eligible respondents were adult women or men (18 years old or older). For households with more than one eligible respondent, the adult with the most recent birthday was selected. Only female interviewers surveyed female respondents, and both women and men surveyed male respondents. A Spanish-language version of the survey was given to Spanish-speaking respondents. Households were called five times on different days and at different times to maximize the response rate. The response rate among those contacted was 72% for women and 69% for men. See Tjaden and Thoennes (2000a) for more detail on the sampling methods and procedures for the NVAWS. The sample used for this study consists of women who reported any violence (physical, sexual, psychological, or stalking) by their current spouse or partner (including same or opposite sex, living together or not living together). Only women who had experienced violence in their current relationship were assessed for PTSD symptoms. 3 Therefore, the sample size for this study was 380. The violence could have occurred at any time during the current relationship. Table 1 presents sample descriptives. The first two columns of Table 1 include descriptives for the full NVAWS sample of women and are presented for comparison purposes. As seen in the third and fourth columns of Table 1, the majority of the women in this sample were White (73.4%), educated with at least a high school diploma (85.5%), married (70.5%), and employed (61.3%). The average age was 40. Measures Adult Victimization by a Current Partner Four types of adult victimization by a current partner were examined. Physical violence was measured by summing an affirmative response to 12 items from the Conflict Tactics Scale (Straus, 1979). Examples of items are yes/no responses to being slapped, hit, kicked, or beaten up. All 12 items were summed to create a scale ranging from 0 (no physical violence) to12(12 types of physical violence). The standardized alpha coefficient for this scale for the sample of women in this study was.83. Sexual violence was measured by summing five items that asked if respondents were ever forced or threatened with force to have vaginal or anal penetration by a penis, fingers, tongue or other object, or oral penetration by a penis or other object by a current partner. All five items were summed 3 Since PTSD symptomatology was not assessed among nonvictims of intimate partner violence, our study does not address whether intimate partner violence victimization increases the risk for PTSD symptoms. Rather, we assess the extent to which victimization experiences among victims of intimate partner violence are related to PTSD symptoms.

4 416 Basile, Arias, Desai, and Thompson Table 1. Sample Descriptives Women responding to Full sample (N = 8, 000) PTSD items a (N = 380) M SD M SD PTSD symptoms NA NA Physical violence Sexual violence Psychological violence Stalking Age % n % n Education , Employed , Hispanic ethnicity Race White , Black or other , Married , a Of the 8,000 women respondents, only women who reported violence by a current partner were asked PTSD items. to create a scale ranging from 0 (no sexual violence) to 5(5 types of sexual violence). The standardized alpha coefficient for this scale for the sample of women in this study was.76. Psychological violence was measured by creating a scale of 13 items assessing power and control tactics. Respondents were asked to think about their current partners and respond with yes or no to statements such as He is jealous or possessive, He tries to limit your contact with family or friends, He makes you feel inadequate, and He insists on knowing who you are with at all times. In addition, one measure of threatening behavior was included as part of the psychological violence measure by asking if the respondent s current partner had ever threatened to harm or kill her. All 14 items were summed to create a scale ranging from 0 (no psychological violence) to12(12 types of psychological violence). The standardized alpha coefficient for this scale for the sample of women in this study was.79. Stalking was measured by summing responses to questions that asked if a current partner had ever committed one or more of eight harassing acts such as: following the respondent or spying on her, standing outside her home, school, or workplace, vandalizing her property or destroying something she loved, or leaving unwanted items for her to find. In line with Tjaden and Thoennes (2000c), respondents were not included as stalking victims unless the stalking happened on more than one occasion and the women were very frightened or believed that they or someone close to them would be seriously harmed or killed when they were being stalked. All eight items were summed to create a scale ranging from 0 (no stalking violence) to 8(8 types of stalking violence). The standardized alpha coefficient for this scale for the sample of women in this study was.89. Posttraumatic Stress Disorder (PTSD) Symptoms Twenty-one items measuring symptoms of posttraumatic stress were adapted from Weiss and Marmar s (1996) revision of the Impact of Event Scale developed by Horowitz, Wilner, and Alvarez (1979). Using a four-point scale (1 = not at all,2= a little bit,3= moderately, and 4 = quite a bit) 4 respondents were asked to reflect on the violence they had experienced with their current partner and indicate how much they were bothered by various difficulties. Examples of items are Any reminder brought back feelings about it, My feelings about it were kind of numb, and I had dreams about it. A mean score of the 21 items was calculated and used in analyses. The standardized alpha coefficient for the 21-item scale for this sample of women was.95. Covariates We controlled for six demographic variables in this study. Age was measured in years. Highest level of education was measured in categories ranging from no schooling to postgraduate level. Employment status was coded as employed (1) or not employed (0). Race was 4 Weiss and Marmar s (1996) revision of the Impact of Event Scale used five response categories instead of four, and contained one additional item that was not included in the NVAWS ( I tried not to talk about it ).

5 Violence and Posttraumatic Stress Symptoms 417 coded as White (1) or Black or other (0) because the sample size did not allow for the examination of other racial groups. Ethnicity was coded as Hispanic (1) or non-hispanic (0). Marital status was coded as married (1) or not married (0). All demographic variables were measured at the time of the survey and are descriptive of respondent characteristics at the time of the survey rather than at the time of victimization. Data Analyses Data were analyzed using multiple regression and hierarchical multiple regression. The dependent variable for all analyses was symptoms of PTSD. First, hierarchical regression models were conducted using one of the four types of violence (physical, sexual, psychological, stalking) by a current partner as a key indicator in each model in order to determine the significance of the association between each type of violence and PTSD symptoms. For each of these models, the six demographic variables were entered into the first step. One of the four types of violence was entered in the second step. Then a multivariate model was run including demographics first, followed by all four types of violence in the second step in order to examine the relative contribution of each type of violence. Finally, a dose-response regression model was conducted, where we examined the effects of experiencing more than one type of violent victimization on PTSD symptoms. Four Z-score variables were created for the four types of IPV, and these four new variables were summed to create a dose variable. The dose variable ranged from 2.56 to A final regression was run in which demographics were added first, followed by the dose variable. For all models, age, education, ethnicity, and race were consistently nonsignificant covariates. Therefore, these four demographic variables were trimmed from the analyses and only employment status and marital status were included as covariates in the final models presented in this paper. For all regression analyses, variance inflation factors (VIF) were examined. VIF is an index of how much the error term is being inflated by collinearity between variables (Fox, 1991). For all variables, the VIF did not exceed 1.30, which indicates that multicollinearity is not a problem between the independent variables. Results The mean scores and standard deviations for the four summed IPV victimization scales are given in Table 1. It appears that among this sample of victimized women, physical and psychological violence are the most common types of violence they reported from a current partner. Although not shown in the table, 93% of victimized women in this sample experienced at least one type of physical violence and 52% of victimized women in this sample experienced at least one type of psychological violence. Sexual and stalking violence were reported less among this sample. Nine percent of the victimized women in this sample experienced at least one type of the five types of sexual violence and 7% of victimized women sampled experienced at least one type of stalking violence. Thus, results for both sexual violence and stalking should be interpreted with caution. The associations between the four types of violence and PTSD symptoms were examined and Phi and Pearson coefficients are presented in Table 2. As seen in Table 2, none of the coefficients between the four types of violence exceeded.44. Results of the regression models assessing the relationship of each type of violence to PTSD symptoms are found in Table 3. Findings revealed, consistent with our first hypothesis, that all four types of violence were significantly related to PTSD symptomatology. Specifically, when controlling for the two demographic variables, physical, sexual, psychological, and stalking violence by a current partner were significantly related to higher levels of PTSD symptoms. In each case, the increase in variance accounted for by the key indicator was significant (physical, F = 53.94, p<.001; sexual, F = 14.18, p <.001; psychological, F = 85.78, p <.001; stalking, F = 22.95, p<.001). Table 4 presents the results of the regression analysis in which all four types of violence were simultaneously included as indicators of PTSD symptoms. After controlling for marital status in Step 1 (F = 8.14, p<.01), findings revealed that physical, psychological, and stalking violence emerged as statistically significant correlates of PTSD symptoms in Step 2 (F = 39.40, p<.001). As shown in Table 4, the R 2 for this model indicates that 39% of the variance in PTSD symptoms was explained by the independent variables. The increase in the R 2 from Step 1 to Step 2 was significant (F = 48.31, p<.001), suggesting that violent victimization contributes significantly to PTSD symptoms over and above demographic variables. Specifically, 36% of the variance in PTSD symptoms is explained solely by the three types of violence added in Step 2. The dose-response model analysis results are presented in Table 5. After controlling for marital status in Step 1, there was a positive association between the dose variable and PTSD symptoms in Step 2. It appears that the more types of current partner violence women experienced, the more likely they were to have PTSD symptoms. The R 2 change between Step 1 and Step 2 was

6 418 Basile, Arias, Desai, and Thompson Table 2. Correlation Coefficients for Covariates, Four Types of Violence, and PTSD Symptoms Types of violence Age 2. Education Employed Ethnicity Race Married Physical violence 8. Sexual violence 9. Psych violence 10. Stalking PTSD symptoms Note. Pearson correlation coefficients are presented for all associations between two continuous variables or between a continuous and a dichotomous variable. Phi coefficients are presented for associations between two dichotomous variables. p<.05. p<.01. p<.001. significant (F = , p <.001), indicating that 32% of the variance in PTSD symptoms is explained solely by the dose variable. This finding confirms hypothesis 3. Discussion The purpose of this study was to examine the relationship between four different types of violence by a current intimate partner and PTSD symptoms. The study allowed us to replicate previous findings regarding the psychological impact of IPV and extend those empirical findings by focusing on a population-based sample of women. The results of our analyses indicated that physical violence, sexual violence, psychological violence, and stalking are related to each other and co-occur. All four forms of violence were related to PTSD symptomatology after controlling for age, education, employment and marital status, and race and ethnicity. Further, physical, psychological, and stalking violence were associated with PTSD symptoms in the multivariate model (Table 4). This finding partially confirms hypothesis 2 and this pattern of results is consistent with previous research (Arias & Pape, 1999; Rothbaum et al., 1992; Vitanza et al., 1995) employing clinical samples. Although the lack of a significant association between sexual violence and PTSD symptoms in the multivariate model (Table 4) may be the result of differential effects of sexual violence relative to other forms of IPV, our failure to find a significant association is likely due to a restricted range of sexual violence. Only 34 women in our sample reported being a victim of sexual violence by a current spouse or partner. Similarly, there were only 31 women who reported stalking by a current partner, however the range of 0 to 8 of the summed stalking variable could explain why it was significant and sexual violence was not. The fact that sexual violence was significant in the bivariate model (Table 3) suggests that sexual violence is associated with PTSD symptoms. It is likely that it fell out of the multivariate model (Table 4) because of its low correlation with PTSD symptoms (Table 2) due to a small sample size. Table 3. Results of Hierarchical Multiple Regressions to Predict PTSD Symptoms Physical Sexual Psychological Stalking Indicators β R 2 β R 2 β R 2 β R 2 Step Employed Married Step Employed Married Key indicator Note. Initial analysis included age, education, employment status, ethnicity, race, and marital status in Step 1 as covariates. This table presents trimmed models. p<.05. p<.01. p<.001.

7 Violence and Posttraumatic Stress Symptoms 419 Table 4. Results of Multivariate Regression Analysis to Predict PTSD Symptoms Indicators β R 2 Step 1 Married.18 Step 2 Married.10 Physical violence.26 Psychological violence.38 Stalking Note. The initial model included age, education, employment status, ethnicity, race, and marital status in Step 1 and physical, sexual, psychological, and stalking violence in Step 2. This table presents a trimmed model. p<.01. p<.001. These findings suggest that sexual violence would likely have been significant in the multivariate model (Table 4) if we had a bigger sample size of sexual violence victims. Stalking, on the other hand, has a slightly higher correlation with PTSD symptoms (Table 2), which could explain why it remained significant in the multivariate model (Table 4). In addition, findings support a doseresponse phenomenon, in which the more types of violence a woman experiences, the more increase in PTSD symptoms. This highlights the importance of examining co-occurring types of violence in future research, as the examination of individual types of violence in isolation of the others could conceal the increased effect of the combined forms of violence on health outcomes such as PTSD symptomatology. Indeed, one of the major strengths of this study is that it examined multiple forms of violence and their association with PTSD symptoms, which has not been done in much of the previous work in this area. This allowed us to determine unique effects of different types of IPV as well as their combined effects. In addition, we focused on current relationships. Often, studies on IPV are designed to examine experiences with victimization by a former partner (Straus, 1979). Further, we used data from a nationally representative sample, so the findings are easily generalized. We also looked at PTSD symptoms, Table 5. Results of Dose Response Analysis to Predict PTSD Symptoms Indicators β R 2 Step 1 Married Step 2 Married Dose variable Note. The initial regression analysis included age, education, employment status, ethnicity, race, and marital status in Step 1 as covariates. This table presents a trimmed model. p<.01. p<.001. which have been suggested to be as harmful as full PTSD and more relevant among victims of IPV than full PTSD (Stein et al., 1997). This study has a few limitations. First, this study is cross-sectional and therefore does not allow for the examination of changes in PTSD symptoms over time and their temporal relationship to the demographic variables and violence. As a result, we do not know if changes in employment and marital status came before or after changes in PTSD symptoms. For example, it could be that a change in employment status (i.e., losing a job) led to increases in PTSD symptomology, but we cannot be sure of the order of events. In addition, it could be that PTSD symptoms would decrease if women left their current violent partners. Longitudinal designs are necessary to determine the temporal relationship between changes in violence and changes in PTSD symptoms. Another limitation of this study is that it does not measure all the variables that could plausibly lead to PTSD symptoms, such as the death of a family member or close friend, a serious illness of the respondent or a family member or close friend, or a natural disaster. There are many unmeasured variables in the NVAWS that could have resulted in PTSD symptoms in the respondent. Related to this, we could not directly compare IPV victims to nonvictims on PTSD symptoms in this study because only respondents who reported violence by a current partner were asked about PTSD symptoms in the NVAWS. Further, some of the types of violence measured in this paper (sexual and stalking violence by a current partner) were not frequently reported in this sample, which could be the reason why sexual violence was not significantly associated with PTSD symptoms in the multivariate model. In addition, NVAWS only focused on individual level outcomes, limiting our understanding of the community or societal effects (i.e., costs to society in terms of workforce hours, sick leave, health care costs, spillover violence in the workplace, effects on children who witness) of IPV victimization. Finally, it is important to point out that while we state that the NVAWS is a nationally representative sample, it does not represent women who do not have telephones and therefore could not be a part of this study. This study has implications for policy and practice. The results strengthen the argument that public health practitioners and policy makers should not overlook the importance of addressing the deleterious effects of all types of IPV (and the combined effect of multiple types) in their efforts to prevent future victimization. The findings also have implications for assessment and treatment of PTSD among IPV victims. Interventions that focus specifically on treatment of PTSD and other mental health issues should address all forms of IPV. Future research

8 420 Basile, Arias, Desai, and Thompson using a longitudinal design would be beneficial to understand the temporal relationship between experiences with IPV and the development of PTSD symptoms. The field would also benefit from future research that examines the difference between IPV victims with subthreshold PTSD versus full PTSD. Future research with larger samples of victims of intimate partner sexual and stalking violence would be beneficial to confirm or disconfirm the association between these two types of violence and PTSD symptoms while controlling for other types of violence. Finally, PTSD symptomatology is one of many outcomes of IPV. Future research could also use a comprehensive model, incorporating individual, family, community and societal level variables as outcomes of IPV, to more completely understand the effects of IPV on women s health. References Aguilar, R. J., & Nightingale, N. N. 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