Penterman and Nijman tested the predictive validity of the Checklist of Risks to the Crisis team (crc). This instrument was specifically designed to assess the risks of aggression from severely disturbed psychiatric patients before they are seen by the crisis team. Any perceived aggression following outreach contact was recorded by means of the Staff Observation Aggression Scale-Revised (soas-r).

The authors performed a forward stepwise logistic regression analyses, but reported no regression coefficients and CI's - only the less informative p-values. Three factors in the CRC were important: the clinical assessment on a visual-analogue scale, an estimate of the number of aggressive persons in the vicinity of the crisis patient concerned and the reporting of crises by the patient himself. Based on these indicators it was possible to predict outwardly directed aggression with a sensitivity of 74% and a specificity of 84%. However, these proportions are inflated because the same data was used to build the model and to evaluate the fit of the model (more background information here).

Aggressive behaviour by patients was observed during 51 of 499 crisis contacts with members of the outreach crisis team. In other words, care workers of the outreach psychiatric crisis team can expect aggression from severely ill patients in about 10% of all cases. If they expect non-aggressive contacts they will be right more often then the model.The authors conclude that an instrument such as the crc will help to get more experienced and more standardization in evaluating risk factors. But for that conclusion no hypothesis testing is warrented.

Penterman B, Nijman H. Assessing aggression risks in patients of the ambulatory mental health crisis team. Community Ment Health J. 2011 Aug;47(4):463-71. doi: 10.1007/s10597-010-9348-7. Epub 2010 Oct 1.

Penterman EJM, Nijman HLI.Assessing aggression in patients of the mental health crisis service. Tijdschrift voor psychiatrie 51(2009)6, 355-364