Empirical studies of violence and mental illness have used many different methods. Current state-of-the-art methods gather information from both subject and collateral interviews as well as official records. Typically these sources are treated as additive. Any report of a violent incident from any source is treated as true and all reported incidents are added to generate estimates of frequency. This paper presents a new statistical technique that uses the level of agreement between the sources of data to adjust those estimates. The evidence suggests that, although the additive technique for using multiple sources correctly estimates how many people are involved, it substantially underestimates the number of incidents. The new technique substantially reduces both false negatives and false positives.

Given the availability of violence risk assessment tools, clinicians are now better able to identify high-risk patients. Once these patients have been identified, clinicians must monitor risk state and intervene when necessary to prevent harm. Clinical practice is dominated by the assumption that increases in psychiatric symptoms elevate risk of imminent violence. This intensive study of patients (N = 132) at high risk for community violence is the first to evaluate prospectively the temporal relation between symptoms and violence. Symptoms were assessed with the Brief Symptom Inventory and threat/control override (TCO) scales. Results indicate that a high-risk patient with increased anger in 1 week is significantly more likely to be involved in serious violence in the following week. This was not true of other symptom constellations (anxiety, depression, TCO) or general psychological distress. The authors found no evidence that increases in the latter symptoms during 1 week provide an independent foundation for expecting violence during the following week.

Prior research has consistently demonstrated an association between substance use and involvement in violence among individuals with mental illness. Yet little is known about the temporal quality of this relationship, largely because longitudinal data required to address this issue are not readily available. This study examined the relationship between substance use (alcohol, marijuana, and other drug use) and violence at the daily level within a sample of mentally ill individuals at high risk for frequent involvement in violence (N = 132). Results support the serial nature of substance use and violence, with an increased likelihood of violence on days following the use of alcohol or multiple drugs, but not the inverse relationship. Implications for the utility of substance use as a risk marker for the assessment of future violence are discussed.

Mental health professionals' (MHPs') accuracy in assessing the risk of violence in female patients is particularly limited. Based on assessments made by 205 MHPs of 605 patients in an emergency room, this study explored potential causes of MHPs' poorer accuracy in assessing women's potential for violence. The dimensions that underlie MHPs' envisioned violence in patients were identified and were compared with those that characterized patients' reported violence during a 6-month follow-up period. There were three key findings from their study. First, violence envisioned by MHPs differed depending on their professional role and varied in its congruence with patients' reported violence. Second, patients' violence was organized by dimensions of domesticity and substance relatedness; women's violent incidents were more domestic than were men's. Third, when MHPs envisioned violence that was highly conditional on psychiatric deterioration and medication noncompliance, violence often did not occur.

To address several key questions in social science research, repeated interviews of individuals drawn from difficult populations are required. This article describes an approach for addressing the challenges associated with longitudinal interview studies, including locating research participants, obtaining reliable and valid interview data over time, and retaining participants across the course of the study. We applied this approach to conduct a study designed to identify changeable risk factors for violence among high-risk people with mental illness. To successfully conduct weekly interviews of these individuals in the community across a 6-month period, we developed a flexible and personalized interview format; carefully selected, trained, and supervised staff; and developed incentives to maximize participant retention. Each of these three steps is discussed as a guide for future longitudinal studies that involve interviewing difficult populations.