Yudofsky et al developed the overt aggressive scale (OAS) to describe verbal and physical aggression by patients. It is easy to complete and provides a reliable rating of aggressive events. It can be used to monitor the type and severity of episodes shown by a patient over time. The authors are from Columbia University College of Physicians and Surgeons and the New York State Psychiatric Institute.


Each episode is treated as a separate event.


For each category, the most severe behavior observed and the most extreme intervention used were rated.


Aggressive behaviors:

(1) verbal

(2) physical against self

(3) physical against objects

(4) physical against other people


The ratings are from 0 (none) to 4 (marked).


Interventions (one or more of the following):

(1) none

(2) talking with patient

(3) places under closer observation

(4) holds patient

(5) immediate medication by mouth

(6) immediate medication by injection

(7) isolation without seclusion (time out)

(8) seclusion

(9) use of restraints

(10) injury requiring immediate medical attention

(11) injury to someone else requiring immediate medical attention


To read more or access our algorithms and calculators, please log in or register.