***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Positive psychotic symptoms , such as threat/"control-override " delusions or comm and hallucinations , have been related to aggression in patients with schizophrenia . However , retrospective data collection has hampered evaluation of the direct influence of psychopathology on aggressive behavior . In this study , we monitored aggressive behavior and psychopathology prospect ively and in close temporal proximity in 157 treatment-resistant in patients diagnosed with chronic schizophrenia or schizoaffective disorder participating in a 14-week double-blind clinical trial . Aggressive behavior was rated with the overt aggression scale ( OAS ) . Psychopathology was assessed using the positive and negative syndrome scale ( PANSS ) . At baseline , subjects who would be aggressive during the study had higher scores on only two PANSS items : hostility and poor impulse control . During the study PANSS positive subscale scores were significantly higher in aggressive subjects . Total PANSS scores were higher within 3 days of an aggressive incident , as were positive and general psychopathology subscale scores . However , in a smaller sub sample for whom PANSS ratings were available within 3 days before aggressive incidents , only scores on the PANSS positive subscale were significantly higher . These findings in chronic , treatment resistant in patients support the view that positive symptoms may lead to aggression This study prospect ively compared the effectiveness of atypical antipsychotic medications to that of conventional neuroleptics in reducing violent behavior  among patients with schizophrenia under " usual care " conditions in the community . Participants ( n = 229 ) were adults with schizophrenia spectrum disorders receiving inpatient or outpatient services in public sector mental health systems in North Carolina . Subjects were followed for 2 years in an observational study using multiple methods of data collection at 6-month intervals to assess treatment , sociodemographic characteristics , clinical features , and violence outcomes . Treatment with atypical antipsychotic medications ( clozapine , risperidone , or olanzapine ) was found to significantly reduce the risk of violent behavior , whereas treatment with conventional neuroleptics did not have this same beneficial effect . A cumulative effect on reduced violence was attributable to consistent compliance with atypical antipsychotic medications over a 2-year period . Concurrent reductions in psychotic symptoms , substance abuse , and adverse medication side effects were found to mediate the association between adherence with atypicals and lower violence risk . Treatment with atypical antipsychotic medications should be considered as an important component of violence risk management for schizophrenia patients at risk for violent behavior BACKGROUND Violence is an uncommon but significant problem associated with schizophrenia . AIMS To compare antipsychotic medications in reducing violence among patients with schizophrenia over 6 months , identify prospect i ve predictors of violence and examine the impact of medication adherence on reduced violence . METHOD Participants ( n=1445 ) were r and omly assigned to double-blinded treatment with one of five antipsychotic medications . Analyses are presented for the intention-to-treat sample and for patients completing 6 months on assigned medication . RESULTS Violence declined from 16 % to 9 % in the retained sample and from 19 % to 14 % in the intention-to-treat sample . No difference by medication group was found , except that perphenazine showed greater violence reduction than quetiapine in the retained sample . Medication adherence reduced violence , but not in patients with a history of childhood antisocial conduct . Prospect i ve predictors of violence included childhood conduct problems , substance use , victimisation , economic deprivation and living situation . Negative psychotic symptoms predicted lower violence . CONCLUSIONS Newer antipsychotics did not reduce violence more than perphenazine . Effective antipsychotics are needed , but may not reduce violence unrelated to acute psychopathology Objective The aim of the present study was to find out the extent of hostility and violence and the factors that are associated with such hostility and violence in a psychiatric intensive care unit . Methods Retrospective analysis of data prospect ively collected in a 6-year period . Results No hostility was observed in 56.1 % , hostility in 40.9 % , and violence in 3.0 % of the admitted cases . Seclusion was never used . Six cases ( 2,5‰ ) required physical restraint . Risk factors associated with violence were younger age , suicidal risk , and diagnosis of schizophrenia . Risk factors associated with hostile and violent behavior were younger age at the onset of the disorder , being single , having no children , lower GAF scores , higher BPRS hostility , SAPS , and CGI scores , lower BPRS anxiety-depression score , higher doses of psychoactive drugs , more frequent use of neuroleptics , diagnosis of mania , personality disorder , substance and alcohol related disorders , no diagnosis of depression . Conclusion The study confirms the low rate of violence among Italian psychiatric in- patients , the major relevance of clinical rather than socio-demographic factors in respect of aggressive behavior , the possibility of a no seclusion-no physical restraint policy , not associated either with higher rates of hostility or violence or with more severe drug side effects Accurate evaluations of the dangers posed by psychiatric in patients are necessary , although a number of studies have question ed the accuracy of violence prediction . In this prospect i ve study , we evaluated several variables in the prediction of violence in 63 in patients with a DSM-IV diagnosis of schizophrenia or schizoaffective disorder .  Nurses rated violent incidents with the Overt Aggression Scale . During hospitalization , sociodemographic variables , clinical history , neurological soft signs , community alcohol or drug abuse , and electroencephalographic abnormalities did not differ between violent and nonviolent groups . Violent patients had significantly more positive symptoms as measured by the Positive and Negative Syndrome Scale ( PANSS ) , higher scores on the PANSS general psychopathology scale , and less insight in the different constructs assessed . A logistic regression was performed to discriminate between violent and nonviolent patients . Three variables entered the model : insight into symptoms , PANSS general psychopathology score , and violence in the previous week . The actuarial model correctly classified 84.13 percent of the sample ; this result is significantly better than chance for the base rate of violence in this study . At hospital admission , clinical rather than sociodemographic variables were more predictive of violence . This finding has practical importance because clinical symptoms are amenable to therapeutic approaches . This study is the first to demonstrate that insight into psychotic symptoms is a predictor of violence in in patients with schizophrenia OBJECTIVE The types and amounts of crime experienced by persons with severe mental illness were examined to better underst and criminal victimization in this population . METHODS Subjects were 331 involuntarily admitted psychiatric in patients who were ordered by the court to outpatient commitment after discharge .  Extensive interviews provided information on subjects ' experience with crime in the previous four months and their perceived vulnerability to victimization , as well as on their living conditions and substance use . Medical records provided clinical data . RESULTS The rate of nonviolent criminal victimization  ( 22.4 percent ) was similar to that in the general population ( 21.1 percent ) . The rate of violent criminal victimization was two and a half times greater than in the general population --8.2 percent versus 3.1 percent . Being an urban resident , using alcohol or drugs , having a secondary diagnosis of a personality disorder , and experiencing transient living conditions before hospitalization were significantly associated with being the victim of a crime . In the multivariate analysis , substance use and transient living conditions were strong predictors of criminal victimization ; no demographic or clinical variable was a significant predictor . ( Given the relatively high crime rates , subjects ' perceived vulnerability to victimization was unexpectedly low ; only 16.3 percent expressed concerns about personal safety . Those with a higher level of education expressed greater feelings of vulnerability . CONCLUSIONS The study found a substantial rate of violent criminal victimization among persons with severe and persistent mental illness . Results suggest that substance use and homelessness make criminal victimization more likely A small group of invited scientists , policy makers , and editors discussed this question at a meeting in London on Sept 24–25 , 2009 , sponsored by the European Centre for Ecotoxicology and Toxicology of Chemicals . A report of the proceedings was published on the host ’s website on Jan 18 . To some , the sponsorship of such a meeting by an agency funded by the chemical industry raises immediate concerns about ulterior motives : how might the registration of observational research benefi t these companies ? Access to subsequent data would be an obvious advantage to industry . But that benefi t extends both ways , as happened when pharmaceutical companies were compelled to register interventional trials . Completeness of information improves decision making , aids systematic review s , and reduces waste from duplication of research . The crucial question is whether registration , by improving the transparency of observational research , would lend greater credibility to its fi ndings , or if such a move would stifl e creativity and delay the communication of important insights . A major consideration is the heterogeneity of purpose as well as methods in observational research . At one extreme , the value of hypothesis-generating observations in a small case series might not be foreseen and its communication should not be constrained by unnecessary bureaucracy . At the other , a large , hypothesis-driven cohort study , with a solid protocol that has taken years to organise and fund , has little excuse not to register its intent . The Lancet family of journals believes that when feasible , investigators should register observational studies on a WHO-compliant registry before they begin . A mechanism already exists for this on many registries , including Clinical Trials.gov , where almost 14 000 observational studies are listed . Furthermore , we welcome inclusion of the protocol when an observational study is su bmi tted , which we will forward in confi dence to peer- review ers . Finally , we encourage authors of accepted observational manuscripts to provide a weblink to their protocol in the published report , just as we do for r and omised trials . We believe that by taking these steps , investigators using observational methods will be able to make a stronger contribution to health care . ■ The The need for reliable evidence for medical interventions has long been recognised and the history of attempts to produce this evidence is thoroughly documented in the James Lind library ( http://www.jameslindlibrary .org/ ) . The status of r and omised controlled trials as the most reliable method for evaluating the effects of treatments is now well established . Although the basic principles of the r and omised trial have a long developmental history , it is often considered that the first modern medical r and omised controlled trial came was the UK Medical Research Council trial of  streptomycin  in the treatment of tuberculosis ( Medical Research Council , 1948 ) . In the years following this trial , many r and omised trials were conducted on a number of key questions in a number of disease areas including psychiatry and mental health . Many of these were funded by national public bodies , particularly 
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When restricting outcomes to severe violence , these associations did not change material ly .
In studies investigating inpatient violence , associations differed in strength but not direction .