Anxiety Assessment in Pre-clinical Tests and in Clinical Trials: A Critical Review.

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.

Depression Assessment in Clinical Trials and Pre-clinical Tests: A Critical Review.

Depression is deeply rooted in human behavior. The development of new antidepressants demands the creation of animal models to investigate new drugs, which potentially could work as antidepressants. The aim of this review is to discuss the different ways of assessing depression in clinical research, including clinical trials, and the different animal behavioral tests used to study depression and test the efficacy of antidepressants in pre-clinical studies. In clinical practice, a categorical classification, such as the Diagnostic and Statistical Manual of Mental Disorders (DSM) and the International Statistical Classification of Diseases and Related Health Problems (ICD) can be used for diagnosis, through the use of structured and semi-structured interviews. On the other hand, depression can also be assessed using a dimensional approach, through self- or clinicianrated questionnaires. Regarding the assessment of the efficacy of antidepressants in animal models, several tests are routinely used, namely the Forced Swim Test, the Modified Forced Swim Test, the Tail Suspension Test and the Sucrose Preference Test. These tests are informative, providing that the following rules are taken into account: 1) more than one test is used, with coherent results; 2) secondary drug effects, the most frequent being putative changes in motor activity, are taken into account and properly controlled with specific tests run concomitantly; 3) each test and specific protocol is validated with data from at least a gold standard antidepressant drug. We herein briefly discuss the potential and limitations of each of those tests.