[Violent and intimidating behavior of psychiatric patients at admission].

The dangerousness of the mentally ill patient is still unknown. This study assesses the actual prevalence of violent and intimidating behaviours in psychiatric patients at the time of their admission, or in the days leading up to their admission to a Quebec hospital. These behaviours have been measured on a six-point scale whose reliability for this population is appropriate. The consecutive sample consists of 383 adult admissions, and the results show that 83.0 percent of the involuntary admissions and 40.7 percent of the voluntary admissions manifested violent or intimidating behaviours at the time of hospitalization. The results support the clinical experience that psychiatric patients often exhibit this type of behaviour on admission.