The identification of anxious symptoms is crucial to diagnose anxiety disorders, as well as to
monitor their treatment in clinical practice and research. The aim of this review is to discuss the different
ways of assessing anxiety in clinical research, including clinical trials, and the different kinds of
animal behavioral tests used to study anxiety and test the efficacy of anxiolytics in pre-clinical studies.
In clinical practice, a categorical classification (such as the Diagnostic and Statistical Manual of Mental
Disorders and the International Statistical Classification of Diseases and Related Health Problems)
distinguishes the cases of the disease versus non-disease. Some structured and semi-structured
interviews can be used to arrive at these diagnoses. On the other hand, anxiety can also be assessed
using a dimensional approach, through self-report or hetero-evaluation questionnaires. Regarding the
assessment of anxiety in animals, several behavioral tests are described and evaluated, namely the
Social Interaction Test, Elevated Plus Maze and Open Field Test. Under a critical view, these two
approaches are presented and discussed, in order to improve the outcome of research in this field.