Modified Overt Aggression Scale

Development and history

The Modified Overt Aggression Scale was first created to assess aggression in psychiatric inpatients, particularly those with autism or other intellectual disabilities. It is commonly used to monitor aggression and aggressive incidents over time, often at one-week intervals, and has later been applied to evaluate how well therapy or medication reduces aggressive behavior in clinical environments. The tool has been adapted into Italian, Chinese, and French. Its scores have demonstrated strong reliability and validity across various research groups.

A 2009 study by Chinese researchers confirmed that the scale consistently measures aggression levels and accurately captures what it intends to. Another study by Ira L. Cohen and colleagues found it to be a reliable and valid way to measure aggressiveness in individuals with intellectual disabilities. The scale also works well for measuring aggression in developing nations, not just in the developed countries where it was first validated.

Limitations

The original version of the scale had problems with its scoring methods, leading some psychologists to view it as not reliable, which prompted revisions. The study on people with intellectual disabilities had minor limitations, as its standards for autistic traits were based on clinical information rather than standard measures from the Autism Diagnostic Interview-Revised, though the large sample size of over 2,000 people mitigates this concern.