An international comparative study on the reliability and validity of the attitudes towards aggression scale

One of the factors known to be associated with the management of patient aggression is the attitude of staff members towards the aggressive behaviour of patients. The construct validity of an instrument measuring the attitudes of staff towards inpatient aggression in psychiatry was evaluated in this international multi-centre study. Factor analysis and simultaneous component analysis were performed with data from a convenience sample of 1769 psychiatric nurses working in psychiatric hospitals and student nurses from nursing schools. The samples were recruited by fellow researchers in their home country. The original 32-item version (POAS) was reduced to 18 items comprising five attitude scales with solid psychometric properties. The types of attitudes were labelled offensive, communicative, destructive, protective and intrusive. The format of the correlations between the types of attitudes suggested the existence of two basic underlying divergent domains in the scale. The 'communication' and 'protection' scale components on the one hand, and the 'offence', 'destruction' and 'intrusion' components on the other. The five types of attitude proved to be invariant across samples from five European countries. The Aggression Scale (ATAS) is a reliable and valid measure that will enable researchers to perform international comparative research on attitudes and aggression.