Gender, Threat/Control-Override Delusions and Violence

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1 DOI /s x ORIGINAL ARTICLE Gender, Threat/Control-Override Delusions and Violence Brent Teasdale Eric Silver John Monahan C American Psychology-Law Society/Division 41 of the American Psychological Association 2006 Abstract This study brings together the threat/control-override perspective and the literature on gender and stress coping to argue that gender moderates the association between threat delusions and violence. We suggest that men are more likely than women to respond to stressors such as threat delusions with violence. We test these ideas using data from the MacArthur Violence Risk Assessment Study, a multi-wave study of post-discharge psychiatric patients. Within-person results from two-level hierarchical models support the idea that men and women cope with threat delusions differently. Specifically, we find that men are significantly more likely to engage in violence during periods when they experience threat delusions, compared with periods when they do not experience threat delusions. In contrast, women are significantly less likely to engage in violence during times when they experience threat delusions, compared with periods when they do not. We discuss these findings in light of the literature on gender and stress coping. Keywords Gender. Violence. Delusions. TCO Introduction Link and Stueve (1994) proposed that the relationship between violence and psychotic symptoms exists because violence is more likely when psychotic symptoms cause a person to feel personally threatened or involve the intrusion of thoughts that can override self-controls (p. 155). B. Teasdale ( ) Department of Sociology, University of Akron, 252 Olin Hall, Akron, OH , USA teasdale@uakron.edu E. Silver Crime, Law, and Justice Program, Department of Sociology, The Pennsylvania State University, USA J. Monahan School of Law, The University of Virginia, USA

2 They called these aspects of psychosis threat/control-override (TCO) symptoms. In a series of studies (Link, Andrews, & Cullen, 1992; Link, Monahan, Stueve, & Cullen, 1999); see also (Link, Stueve, & Phelan, 1998), Link and colleagues reported that this particular constellation of delusional beliefs, and not other delusions, was largely responsible for the violent behavior of people with mental disorders. In addition to the pioneering studies by Link and colleagues, the relationship between threat/control-override delusions and violence has received a great deal of empirical attention by others (Appelbaum, Robbins, & Monahan, 2000; Hodgins, Hiscoke, & Freese, 2003; Stompe, Ortwein-Swoboda, & Schanda, 2004; Swanson, Borum, Swartz, & Monahan, 1996; Swanson et al., 1997). All of the early studies demonstrated strong empirical support for a relationship between TCO symptoms and violence (Link et al., 1999; Link&Stueve,1994; Swanson et al., 1996, 1997). Recently, however, a pair of studies has challenged the assertion that TCO delusions are correlated with the violent behavior of psychiatric patients (Appelbaum, Robbins, & Monahan, 2000; Stompe, Ortwein-Swoboda, & Schanda, 2004). Debate over the association between TCO symptoms and violence has occurred largely absent a focus on gender. Indeed the majority of studies supporting the TCO perspective were based on male-only samples or samples where the majority of the violence was committed by males (see for example: (Hodgins, Hiscoke, & Freese, 2003; Swanson et al., 1996, 1997). These studies necessarily focus on the effect of TCO delusions on male-perpetrated violence. For example, a recent study challenging the TCO theory (Appelbaum, Robbins, & Monahan, 2000) utilized data that included more female perpetrated violence than previous studies. The absence of a correlation between TCO delusions and violence in Appelbaum and colleagues (Appelbaum, Robbins, & Monahan, 2000) data requires further explanation. We argue that such an explanation requires a more careful examination of the differential effect of TCO delusions on male and female violence, and a more careful examination of the role that gender plays in the association between violence and each of the components of the threat/control override construct. Indeed, we suggest that the absence of a correlation between TCO delusions and violence in Appelbaum and colleagues (Appelbaum, Robbins, & Monahan, 2000) study reflects a differential response to threat delusions by males and females that, when examined together, cancel each other out. There is good reason to believe that men and women may respond differently to the presence of TCO delusions. Indeed, the recent literature on gender and the stress process suggests that men and women respond to life stress differently. While men characteristically respond to stress with a fight or flight reaction, women are more likely to engage in tend and befriend behaviors in response to stress (Stroud, Salovey, & Epel, 2002; Taylor, Klein, Lewis, Gruenewald, Gurung, & Updegraff, 2000). That is, men as a group tend to engage in aggressive behavior in response to stress, while women as a group tend to respond to stress by nurturing social relationships. Thus we hypothesize that stressful events, such as the delusion that one is being threatened by another, will lead to higher rates of violence among men and lower rates of violence among women. We expect this pattern because during times of stress men are more likely than women to resort to fight or flight behavioral coping strategies that include violence, while women are more likely to seek out friends for support and nurturance, making them less likely to engage in violence. 1 1 We acknowledge that the stress coping perspective is only one possible explanation for our hypothesized findings, a point which we return to in the discussion. The gendered nature of stress coping provided the theoretical basis for our empirical expectations and is therefore presented in some detail in the introduction. It also stands in contrast to expectations derived from symbolic interactionist theory, upon which the TCO perspective was developed. We thank an anonymous reviewer for pointing out that alternative explanations for this pattern of findings may also be reasonable.

3 Based on symbolic interactionist principles, Link and Stueve (1994) argued that when TCO delusions are believed to be real, they are real in their consequences. Specifically, if an individual, regardless of gender, believes that he or she has been threatened (a threat delusion), then he or she will respond to that threat as though it was real. Link et al. (1999) suggested that violence is a possible and likely response to such perceptions of threat. In contrast to the expectations derived from symbolic interactionist theory, we argue that men and women are likely to cope with a threat delusion in very different ways. Men are expected to engage in fight or flight behavior, thus increasing the likelihood of violence in response to the delusion. Women, in contrast, are expected to engage in tend and befriend behaviors, thus decreasing the likelihood of a violent response to the delusion. Seeking out friends to help navigate the stressful period (i.e. to cope with the delusions) should reduce the likelihood of violent behavior because violence is antithetical to women s more typical coping strategy of nurturance and emotional support. Furthermore, in their previous work, Link and colleagues found that both threat delusions and control-override delusions were independently and significantly related to violence (Link, Stueve, & Phelan, 1998). Specifically, they found that a measure of control-override delusions combining two self-report items and a psychiatrist s rating of the patient on the Schedule for Affective Disorders and Schizophrenia (SADS) was significantly and positively related to both fighting and weapon use. Similarly, a measure of threat delusions based on the question How often have you felt that there were people who wished to do you harm? was significantly and positively related to fighting and weapon use. Therefore, in analyzing the effect of TCO delusions on violence for males and females we follow Link et al. (1998) and break the TCO construct down into its constituent parts (e.g., threat and control-override). In addition, to be consistent with prior literature in this area, we also analyze the effect of TCO delusions on violence using a single measure of TCO delusions consisting of both the threat and control-override components. Method The data for this study come from the MacArthur Violence Risk Assessment study (for a detailed description of the study, see Monahan et al., 2001; Silver, Mulvey, & Monahan, 1999; Steadman et al., 1998). In brief, the MacArthur Study is a multi-wave study of violence by post-discharge psychiatric patients. The sample was collected using a stratified random sampling design. All inpatient admissions at three psychiatric facilities (in Pittsburgh, PA, Worchester, MA, and Kansas City, MO) were screened for eligibility. The sample was stratified by gender, race, and age. Within each stratum, a random sample of eligible participants was approached for inclusion in the study. Continuous enrollment in the study occurred until a quota for each stratum was reached. Approximately 18% of the subjects were diagnosed with a schizophrenic disorder, 44% with a depressive disorder, 14% with a manic disorder, and 23.4% of the subjects were diagnosed with a substance abuse disorder. After discharge from the hospital, study participants were re-interviewed once every ten weeks over the course of one year. These five post-release interviews provided the within-subject data we analyzed for the current study. Measures Violence Information about subject violence was obtained from multiple sources including the follow-up interviews with the respondents (protected by a Federal Confidentiality Certificate), interviews with collateral informants, and official records. Each subject and collateral informant was asked

4 whether the subject had engaged in several categories of aggressive behavior over the past 10 weeks. Violence was defined as (1) batteries that resulted in physical injury or involved the use of a weapon, (2) threats made with a weapon in hand, or (3) sexual assaults (Appelbaum, Robbins, & Monahan, 2000). If the subject had engaged in one of these behaviors during the past 10 weeks, the subject was coded as violent for that wave. This resulted in a dichotomous indicator of violence (1 if yes) for each wave of data included in the study. Because of the nested structure of the data (e.g., waves nested within individuals) and because of the dichotomous coding of the dependent variable, violence, we used a hierarchical binomial generalized linear model to analyze the data (details are provided below). Delusions Delusions were assessed using the Diagnostic Interview Schedule (DIS). Clinically trained interviewers were instructed to determine, based upon DSM criteria, whether participants were definitely delusional, possibly delusional, or not delusional. Participants who were initially rated as possibly or definitely delusional were assessed using a more detailed instrument, the MacArthur-Maudsley Assessment of Delusions Schedule, which yields information about conviction, negative affect, acting on belief, refraining from acting because of belief, preoccupation, and pervasiveness (Appelbaum, Robbins, & Monahan, 2000). In addition, the delusions were coded for content. Delusions that involved persecution were coded as threat delusions. These included the belief that people were spying on the subject, the belief that people were following the subject, the belief that the subject was being secretly tested or experimented on, or the belief that someone was plotting against the subject or trying to harm them. Delusions involving body or mind control or thought broadcasting were coded as control-override delusions. Examples of these delusions included the belief that strange thoughts or thoughts that were not the subject s were being put directly into their mind, the belief that someone or something could take or steal thoughts from the subject s mind, the belief that special messages were being sent to the subject through the television or radio, or the belief that strange forces were working on (the subject), as if (he or she) was being hypnotized or magic was being performed on (him or her), or (he or she) was being hit by x-rays or laser beams. The delusions were originally coded by the interviewers, and all coding was reviewed by an experienced psychiatrist (see Monahan et al., 2001,p.73). Gender Gender is a dichotomous indicator with males coded as 1 and females coded as 0. Time Time is coded as a series of dummy variables. The reference category for this series of dummy variables is the first wave of interview data. We include the time dummy variables so that our results are not influenced by the stable trend across waves in the dependent variable, violence. That is, we wish to investigate the correlation between changes in the dependent and independent variables, net of their time stable trends. In addition, we include an error term for the linear trend across waves. This adjusts the model for serially correlated error (autocorrelation) across study waves so that our results are not influenced by correlated error due to waves of data that are closer together in time being more similar to one another than waves that are spaced further apart.

5 Data analysis The design of the MacArthur study allows us to use each person as their own control to estimate within-person models of violent behavior that partial out all time stable characteristics, both measured and unmeasured (Horney, Osgood, & Marshall, 1995). Partialing out time stable factors leaves only within-person changes in violence as the outcome measure, so that predictors in our model can only be correlated with within-person variation in violence over the one year period following hospital discharge. We accomplish this by converting the predictor and outcome variables in our model to deviations from the within-person mean for each subject, a technique known as group-mean centering (for centering choices see Britt, 2000). Thus, our model measures within person changes over time in violence as a function of withinperson changes in the independent variables of interest, controlling for all possible time stable characteristics. 2 In addition, due to the dichotomous nature of the dependent measure, we utilize hierarchical generalized linear modeling with a Bernoulli distribution (Bryk & Raudenbush, 1992). This technique takes into account the dichotomous nature of the outcome measure, violence, and produces regression coefficients that can be exponentiated to yield odds ratios (see Griffin & Armstrong, 2002; Guo & Zhao, 2000; Ulmer & Johnson, 2004). Finally, this technique allows us to take into account several elements of the survey design. First, multiple observations from the same person over time tend to share error variance. The inclusion of a person level error term (µ i ), in addition to the wave-level error term (r it ), allows us to account for the variance that is common across waves of data for each individual. In addition, data waves that are closer together in time usually are more similar to one another than those that are temporally further apart, a phenomenon known as serial autocorrelation (Ware, 1985). The hierarchical model used here allows us to account for serial autocorrelation by including an error term for the linear time trend. This error term accounts for error variation shared between data waves that occur closer together in time. The sample consists of 902 men and women who completed at least two study waves. Unlike repeated measures analysis of variance, the hierarchical linear model (HLM) procedure employed here does not require complete data from each subject at all waves of measurement. Instead HLM estimates the within person relationships for participants who provide at least two waves of data (those participants for whom it is possible to estimate a random intercept), and the model gives greater weight to subjects with more waves of data. Consequently we are able to use data from all of the 902 subjects, even if they drop out of the study. Estimates of the within-person relationships are based on the available data for each subject. Results Sample description Table 1 shows the proportion of study participants who experienced TCO delusions and violence over the five waves of data included in this study. As shown, the majority of the respondents did not engage in any violence across study waves. Additionally, the proportion engaging in violence decreased over time. Similarly, only a small proportion of subjects experienced a threat delusion 2 The real power of these designs lies in their ability to control for unmeasured time stable variables in survey research, largely ruling out the possibility of selection bias (see Horney, Osgood, & Marshall, 1995, for a discussion of these methods).

6 Table 1 Proportions for study variables across waves Wave 1 Wave 2 Wave 3 Wave 4 Wave 5 Within Person Variables Violence Threat delusion Control-override delusion TCO delusion Between Person Variable Male 0.57 (between 5 and 7%) or a control override delusion (between 4 and 6%) during the year following hospital discharge. In addition, the proportion of subjects experiencing a delusion of either type decreased with time. The sample is fairly evenly split between males (57%) and females (43%). Of the women, 64 (16.7%) experienced a threat delusion and 44 (11.4%) experienced a control override delusion. Of the men, 94 (18.2%) experienced a threat delusion and 84 (16.2%) experienced a control-override delusion. TCO delusions and violence Table 2 presents the results of a two-level hierarchical linear model predicting violence. As shown in Model 1 of Table 2, males are significantly more likely to engage in violence than females (odds ratio = 1.46). This finding is consistent with much of the literature on violent behavior (Felson, 2002); but see (Robbins, Monahan, & Silver, 2003). The remainder of the table shows the associations with violence of three types of delusions: threat delusions, controloverride delusions, and a combined measure of threat/control-override delusions. As shown, the main effect of threat delusions is significant and negative (odds ratio = 1.41). This indicates that across waves of data measured within person, threat delusions are associated with lower levels of violent behavior. However, this main effect is qualified by a significant gender by threat delusions interaction (odds ratio = 1.55). Consistent with our hypothesis, the interaction suggests that when males experience threat delusions they exhibit higher rates of violence; whereas when females experience threat delusions they exhibit lower levels of violence. Figure 1 illustrates Table 2 Two-level hierarchical generalized linear models predicting violence Model 1 Model 2 Model 3 β Partial Partial odds ratio β odds ratio β Partial odds ratio Between Person Variables (n = 902) Gender (male = 1) Within Person Variables (n = 3,677) Threat delusions Control-override TCO delusions Cross Level Interactions Gender threat Gender control-override Gender TCO p <.05; p <.01; p <.001.

7 Male Female Threat Delusion Yes Threat Delusion No Fig. 1 Predicted odds of violence for gender and threat delusions this effect. Neither the main effect of control-override delusions nor its interaction with gender is significantly related to violence (see Fig. 2). Importantly, the combined threat /control-override measure exhibits a relationship with violence that reflects a combination of the effects of threat delusions and control-override delusions. Specifically, when a woman experiences a TCO delusion, she is significantly less likely to engage in violence, compared with times when she does not experience a TCO delusion. In contrast, there appears to be no effect of TCO delusions on male violence. These effects are illustrated in Fig. 3. This is likely the result of the competing effects of threat and control override delusions for men (see Figs. 1 and 2). Specifically men are more likely to respond to threat delusions with violence and less likely to respond to control-override delusions with violence. These two effects cancel out in the composite TCO measure among men. This finding highlights the importance of considering threat and control-override delusions separately. Finally, in Model 3 of Table 2, we estimate a model that controls for gender but does not specify the interaction between gender and TCO delusions on violence. Although we use a different analytical technique, this model finds similar results to the study by Appelbaum and colleagues (Appelbaum, Robbins, & Monahan, 2000). Specifically, there is a main effect of gender on violence, but TCO delusions do not have a significant relationship with violence, controlling for gender. Consequently, it is necessary to look at the effect of each type of delusion Control-Override Delusion Yes Control-Override Delusion No Male Female Fig. 2 Predicted odds of violence for gender and control-override delusions

8 Male Female TCO Delusion Yes TCO Delusion No Fig. 3 Predicted odds of violence for gender and threat/control-override delusions (threat and control override) separately for each gender in order to avoid making a type two error. Discussion This study indicates that males measured as part of the MacArthur Violence Risk Assessment Study were more likely than females measured in the same study to respond to threat delusions with violence. This finding is consistent with the developing literature on the gendered nature of stress coping, which suggests that males tend to respond to threat with a fight-or-flight response that may include violence, whereas females tend to respond to threat with a tend-and-befriend coping strategy that does not include violence (Stroud, Salovey, & Epel, 2002; Taylor et al., 2000). However, although our data are consistent with the notion that females engage in tend and befriend coping strategies in response to threat delusions, while males respond with fight or flight strategies that include violence, the data required to directly examine these mediating mechanisms were not gathered as part of the MacArthur study and therefore could not be tested here. Such an examination must await future research. Nonetheless, the results of this study contribute to the debate about the role of TCO delusions in violence. As mentioned above, a number of prior studies found strong support for the TCO perspective (Link et al., 1999; Link&Stueve,1994; Swanson et al., 1996, 1997). However, more recent studies have questioned the role of TCO delusions in violence (Appelbaum, Robbins, & Monahan, 2000; Stompe, Ortwein-Swoboda, & Schanda, 2004). Importantly, Appelbaum et al. (2000), using the same data set examined here, investigated the main effect of TCO delusions on violence and found no significant effects. As shown in Model 2 of Table 2 andinfig. 1, threat delusions have opposite effects on male and female violence. Due to the opposite direction of the effect of threat delusions on men and women, it is likely that these effects cancelled each other out in the results of the Appelbaum and colleagues study (see also model 3 of Table 2). Based on the results reported here, future research in this area must take into account the differential impact of threat delusions on male and female violence. More broadly, the results of this study suggest that a one size fits all main-effects approach to risk assessment may be unwarranted (Monahan et al., 2001). Variables known to increase male violence, such as TCO delusions, may not operate in similar fashion for females. Practitioners

9 need to be sensitive to gender and other status characteristics that may modify the effects of risk factors on violent behavior (Lidz, Muley, & Gardner, 1993; Robbins, Monahan, & Silver, 2003). Although we highlight gender in this paper, other characteristics that may be taken into account include race/ethnicity, cultural differences, and social class. Thus, future studies of the effects of risk factors on violence committed by individuals with a mental disorder should take into account possible interactions between these status characteristics and other risk factors for violence. We believe this study provides an example of theoretically grounded empirical research that attempts to do just this, and we encourage increased attention to these issues. References Appelbaum, P., Robbins, P., & Monahan, J. (2000). Violence and delusions: Data from the MacArthur violence risk assessment study. American Journal of Psychiatry, 157, Britt, C. (2000). Social context and racial disparities in punishment decisions. Justice Quarterly, 17, Bryk, A., & Raudenbush, S. (1992). Hierarchical linear models. Newbury Park, CA: Sage Publications. Felson, R. (2002). Violence and gender reexamined. Washington, DC: American Psychological Association. Griffin, M., & Armstrong, G. (2002). The effect of local life circumstances on female probationer s offending. Justice Quarterly, 20, Guo, G., & Zhao, H. (2000). Multilevel modeling for binary data. Annual Review of Sociology, 26, Hodgins, S., Hiscoke, U., & Freese, R. (2003). The antecedents of aggressive behavior among men with schizophrenia: A prospective investigation of patients in community treatment. Behavioral Sciences and the Law, 21, Horney, J., Osgood, D., & Marshall, I. (1995). Criminal careers in the short term: Intra-individual variability in crime and its relation to local life circumstances. American Sociological Review, 60, Lidz, C., Muley, E., & Gardner, W. (1993). The accuracy in assessment of psychiatric inpatients risk of violence. American Journal of Psychiatry, 148, Link, B., Andrews, H., & Cullen, F. (1992). The violence and illegal behavior of mental patients reconsidered. American Sociological Review, 57, Link, B., Monahan, J., Stueve, A., & Cullen, F. (1999). Real in their consequences: A sociological approach to understanding the association between psychotic symptoms and violence. American Sociological Review, 64, Link, B., & Stueve, A. (1994). Psychotic symptoms and the violent/illegal behavior of mental patients compared to community controls. In J. Monahan & H. Steadman (Eds.), Violence and mental disorder. Chicago, IL: University of Chicago Press. Link, B., Stueve, A., & Phelan, J. (1998). Psychotic symptoms and violent behaviors: Probing the components of threat/control-override symptoms. Social Psychiatry and Psychiatric Epidemiology, 33, S55 S60. Monahan, J., Steadman, H., Silver, E., Appelbaum, P., Robbins, P., Mulvey, E., Roth, L., Grisso, T., & Banks, S. (2001). Rethinking risk assessment: The MacArthur study of mental disorder and violence. New York: Oxford University Press. Robbins, P., Monahan, J., & Silver, E. (2003). Mental disorder and violence: The moderating role of gender. Law and Human Behavior, 27, Silver, E., Mulvey, E., & Monahan, J. (1999). Assessing violence risk among discharged psychiatric patients: Toward an ecological approach. Law and Human Behavior, 23, Steadman, H., Mulvey, E., Monahan, J., Robbins, P., Appelbaum, P., Grisso, T., Roth, L., & Silver, E. (1998). Violence by people discharged from acute psychiatric inpatient facilities and by others in the same neighborhoods. Archives of General Psychiatry, 55, Stompe, T., Ortwein-Swoboda, G., & Schanda, H. (2004). Schizophrenia, delusional symptoms, and violence: The threat/control-override concept reexamined. Schizophrenia Bulletin, 30, Stroud, L., Salovey, P., & Epel, E. (2002). Sex differences in stress responses: Social rejection versus achievement stress. Biological Psychiatry, 52, Swanson, J., Borum, R., Swartz, M., & Monahan, J. (1996). Psychotic symptoms and disorders and the risk of violent behavior in the community. Criminal Behavior and Mental Health, 6, Swanson, J., Estroff, S., Swartz, M., Borum, R., Lachicotte, W., Zimmer, C., & Wagner, R. (1997). Violence and severe mental disorder in clinical and community populations: The effects of psychotic symptoms, comorbidity, and lack of treatment. Psychiatry, 60, 1 22.

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