The Depression Anxiety Stress Scales 21, or DASS-21, is a self-report questionnaire designed to measure the severity of symptoms related to three distinct negative emotional states. It is a widely used screening tool that provides a quantifiable measure of distress. The questionnaire consists of 21 items, with respondents rating how much each statement has applied to them over the past week. The DASS-21 is the short-form version of the original 42-item DASS and is intended for use with adults and older adolescents from the age of 17.
The Three Scales of Measurement
The DASS-21 is structured around three distinct, yet related, emotional states: depression, anxiety, and stress. The depression scale measures symptoms beyond just a low mood. It assesses levels of hopelessness, a devaluation of life, low self-esteem, and a lack of interest or involvement in daily activities. This scale also captures anhedonia, the inability to experience pleasure, and inertia, a state of inactivity.
The anxiety scale focuses on the subjective experience of fear and the physiological responses associated with it. It includes items that measure autonomic arousal, such as a racing heart or dryness of the mouth, and skeletal muscle effects like trembling. The scale also evaluates situational anxiety and the general subjective feeling of being anxious.
The stress scale is designed to assess a state of persistent tension and nervous arousal. Its questions target symptoms such as difficulty relaxing, irritability, and being easily agitated or over-reactive. This scale also measures impatience and the feeling of being chronically on edge.
How the Questionnaire is Administered and Scored
The DASS-21 is a self-administered tool that requires no special training to complete or score. Participants respond to 21 statements, rating each one based on how much it applied to them during the previous week. A 4-point severity scale is used for each item, where 0 indicates the statement “Did not apply to me at all” and 3 indicates it “Applied to me very much, or most of the time.”
Each of the three scales—Depression, Anxiety, and Stress—is composed of seven specific questions. To calculate the score for a single scale, the ratings for the seven corresponding questions are summed. This provides a raw score for that emotional state.
To make the DASS-21 scores comparable to the full 42-item DASS, the raw score for each of the three scales must be multiplied by two. This produces the final scores that are then used for interpretation.
Interpreting Your DASS-21 Results
The final scores for each scale can be compared against a set of severity ratings to understand the level of distress. These ratings classify the scores into five levels: Normal, Mild, Moderate, Severe, and Extremely Severe. The score ranges are different for each of the three emotional states.
For the Depression scale, a score of 0-9 is considered Normal. Scores of 10-13 fall into the Mild range, 14-20 are Moderate, 21-27 are Severe, and a score of 28 or higher is classified as Extremely Severe.
The Anxiety scale uses a different set of ranges. A score of 0-7 is Normal, while 8-9 is considered Mild. The Moderate range for anxiety is 10-14, the Severe range is 15-19, and scores of 20 or more are rated as Extremely Severe.
For the Stress scale, the score brackets are higher overall. The Normal range extends from 0-14, and the Mild range is 15-18. A score of 19-25 is classified as Moderate, 26-33 is Severe, and a score of 34 or higher is considered Extremely Severe.
Limitations and Professional Context
The DASS-21 is a screening tool, not a diagnostic instrument. It can indicate the presence and severity of symptoms, but it cannot provide a formal clinical diagnosis for conditions like major depressive disorder or an anxiety disorder.
The results from the DASS-21 provide a measure of a person’s emotional state over the past week. They are not definitive and should not be used for self-diagnosis. A questionnaire score is just one piece of information.
Any scores, particularly those in the moderate to extremely severe ranges, should be discussed with a qualified professional, such as a doctor or mental health clinician. A professional can conduct a comprehensive clinical examination and determine an appropriate course of action. The questionnaire is a starting point for a conversation about mental health, not the final word.