Press Releases

New Study Confirms Treatment Reduces Violence in Individuals with Major Psychiatric Disorders by Half

May 14 1998

Arlington, VA - A new study of violence by patients discharged from psychiatric hospitals conclusively demonstrates what many people have long suspected: treating individuals with major psychiatric disorders markedly reduces episodes of violent behavior. "This proves the importance of treatment in decreasing violent behavior," said Dr. E. Fuller Torrey, Board President of the NAMI Treatment Advocacy Center.

The study, involving 1,696 patients admitted to psychiatric facilities, was carried out as part of the MacArthur Foundation Violence Risk Assessment Study and is published in this month's Archives of General Psychiatry. It found that 15.8 percent of individuals with a major mental disorder had committed a violent act during the 10-week period prior to hospitalization and treatment. During the five 10-week periods following hospitalization and treatment, an average of only 7.9 percent of these same individuals committed a violent act, a reduction of 50 percent. For individuals with a major mental disorder and concurrent alcohol and drug abuse, the effect of treatment in reducing violence was even more dramatic, from 22.6 percent to 10.3 percent, or a reduction of 54 percent.

Violent acts were defined in the study as threatening to use or using a weapon; committing sexual assaults; and kicking, biting, choking, hitting, or beating up another person. Family members were the victims of violence 51 percent of the time. In 35 percent of the cases, a friend was the victim and in 14 percent of the cases, the victim was a stranger. "The study's results confirm what families already know," said Laurie Flynn, NAMI executive director. "Many experience the agony of wanting to help loved ones with severe, untreated mental illnesses, while at the same time fearing them."

Dr. Torrey commended the methodology of the study for including multiple sources of information and categorizing incidents by type of violence. He noted, however, that the demonstrated effectiveness of hospitalization and treatment would have been even greater if the study had included more individuals with major mental disorders who are known to have a higher incidence of violence, specifically those who are homeless or in jail and those with criminal (versus civil) commitment to hospitals. In addition, 29 percent of the original patients refused to participate, and 20 percent more dropped out or were lost to follow up after discharge.

"Given these findings, we must now work to ensure that high quality treatment is made available," said Torrey. “Getting good treatment is especially difficult for individuals with brain disorders who lack insight into their illness and need for treatment. In these cases, it is sometimes necessary to legally mandate treatment using such mechanisms as involuntary outpatient commitments, conservatorships, and conditional release."

Mary Zdanowicz, Executive Director of the NAMI Treatment Advocacy Center, expressed concern that the study neglected to emphasize the clear effect of treatment in decreasing violent behavior. "The NAMI Treatment Advocacy Center wishes to promote this most important finding--that treatment is the key to reducing violence among individuals who are severely ill and, therefore, should be made accessible to those who need it," she said.

The NAMI Treatment Advocacy Center is a nonprofit organization dedicated to promoting and supporting the adoption and implementation of laws and practices that increase access to timely and humane treatment for people who suffer from serious brain disorders such as schizophrenia, manic-depressive illness, and major depression. The Center is a supporting organization of NAMI and is completely funded by the Theodore and Vada Stanley Foundation.


In recent years, increasing evidence has accumulated that individuals with major psychiatric disorders, such as schizophrenia and manic-depressive disorder, are more likely to be violent if they do not receive the medications and other treatments needed to prevent the recurrence of their illness. In one study, psychiatric patients were three times more likely to have been violent (use of weapon, hurt someone badly) than other community residents (Link et al., American Sociological Review 57:275-92, 1992).

In another study, 11 percent of individuals with major psychiatric disorders had harmed another person within the preceding year, and an additional 12 percent had threatened to do so (Steinwachs, D.M. et al. Innovations and Research 1:21-23, 1992). Family members are the victims of such violence in the majority of cases. The most serious cases involve homicide, and there have been estimates that approximately 1,000 homicides each year in the United States are carried out by individuals with major psychiatric disorders who are not being treated (Torrey, Out of the Shadows, 1997, Chapter 4).

Data taken from the MacArthur study clearly demonstrates the effectiveness of treatment in reducing such violence by 50 percent:


Percent of Patients Who Committed Violent Acts
in Specific 10-week Periods,
(Data from Table 4)


  During 10-week period prior
to hospitalization and
Average for five 10-week
periods after hospitalization and
Major mental disorder without alcohol or drug abuse 8.9% 5.5%
Major mental disorder with alcohol or drug abuse 22.6% 10.3%
Average for combined groups 15.8% 7.9%

The other major finding of the study was that alcohol and/or drug abuse is a major risk factor for violence among all individuals, psychiatrically ill or not, thus replicating many previous studies.