Distinguishing between depression and anxiety: a proposal for an extension of the tripartite model.
OBJECTIVE
The aim of the current study was to develop scales that assess symptoms of depression and anxiety and can adequately differentiate between depression and anxiety disorders, and also can distinguish within anxiety disorders. As point of departure, we used the tripartite model of Clark and Watson that discerns three dimensions: negative affect, positive affect and physiological hyperarousal.


METHODS
Analyses were performed on the data of 1449 patients, who completed the Mood and Anxiety Symptoms Questionnaire (MASQ) and the Brief Symptom Inventory (BSI). From this, 1434 patients were assessed with a standardized diagnostic interview.


RESULTS
A model with five dimensions was found: depressed mood, lack of positive affect, somatic arousal, phobic fear and hostility. The scales appear capable to differentiate between patients with a mood and with an anxiety disorder. Within the anxiety disorders, somatic arousal was specific for patients with panic disorder. Phobic fear was associated with panic disorder, simple phobia and social anxiety disorder, but not with generalized anxiety disorder.


CONCLUSIONS
We present a five-factor model as an extension of the tripartite model. Through the addition of phobic fear, anxiety is better represented than in the tripartite model. The new scales are capable to accurately differentiate between depression and anxiety disorders, as well as between several anxiety disorders.
den Hollander-Gijsman
M E
ME
Department of psychiatry, Leiden University Medical Center (LUMC), PO-box 9600, 2300 RC Leiden, The Netherlands. m.e.den_hollander@lumc.nl
de Beurs
E
E
van der Wee
N J A
NJ
van Rood
Y R
YR
Zitman
F G
FG
D000293:Adolescent; D000328:Adult; D000339:Affect; D000368:Aged; D000369:Aged, 80 and over; D001007:Anxiety / Q000523:psychology*; D001008:Anxiety Disorders / Q000145:classification / Q000175:diagnosis* / Q000523:psychology; D003863:Depression / Q000523:psychology*; D003866:Depressive Disorder / Q000175:diagnosis* / Q000523:psychology; D003937:Diagnosis, Differential; D005239:Fear / Q000523:psychology*; D005260:Female; D006791:Hostility; D006801:Humans; D008297:Male; D008875:Middle Aged; D008960:Models, Psychological; D016584:Panic Disorder / Q000175:diagnosis; D010698:Phobic Disorders / Q000175:diagnosis; D011237:Predictive Value of Tests; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires / Q000592:standards*