The DASS is a quantitative measure of distress along the 3 axes of depression, anxiety* and stress**. It is not a categorical measure of clinical diagnoses.
Emotional syndromes like depression and anxiety are intrinsically dimensional - they vary along a continuum of severity (independent of the specific diagnosis). Hence the selection of a single cut-off score to represent clinical severity is necessarily arbitrary. A scale such as the DASS can lead to a useful assessment of disturbance, for example individuals who may fall short of a clinical cut-off for a specific diagnosis can be correctly recognised as experiencing considerable symptoms and as being at high risk of further problems.
However for clinical purposes it can be helpful to have ‘labels’ to characterise degree of severity relative to the population. Thus the following cut-off scores have been developed for defining mild/moderate/severe/ extremely severe scores for each DASS scale.
Note: the severity labels are used to describe the full range of scores in the population, so ‘mild’ for example means that the person is above the population mean but probably still way below the typical severity of someone seeking help (ie it does not mean a mild level of disorder.
The individual DASS scores do not define appropriate interventions. They should be used in conjunction with all clinical information available to you in determining appropriate treatment for any individual.
*Symptoms of psychological arousal
**The more cognitive, subjective symptoms of anxiety