DASI Calculator (Duke Activity Status Index)
The DASI calculator estimates the functional capacity of a patient. The tool is based on the Duke Activity Status Index, a questionnaire that is used to get an estimate of a patient's peak oxygen uptake (VO2 max) and to evaluate the health of patients with cardiovascular disease.
We try our best to make our Omni Calculators as precise and reliable as possible. However, this tool can never replace professional medical advice.
What is Duke Activity Status Index (DASI)?
Hlatky and colleagues developed the Duke Activity Status Index in 1989. DASI is a 12-item scale in the form of a self-administered questionnaire. Clinicians mainly use it to evaluate patients with cardiovascular diseases, such as heart failure, coronary artery disease, or myocardial infarction.
The clinical use of the Duke Activity Status Index includes:
- Measuring functional capacity;
- Assessing aspects of quality of life;
- Estimating peak oxygen uptake;
- Evaluating the effect of medical treatments and/or cardiac rehabilitation; and
- Assisting clinical decisions.
If you are interested in predicting the risk of ischemia or infarction, check the Duke Treadmill Score calculator.
How to calculate DASI score?
DASI is a 12-item questionnaire that assesses daily activities such as household tasks, personal care, and recreation. It also provides the respective metabolic cost; each of the items has a specific weight based on the metabolic cost of task (MET).
💡 Metabolic Equivalent of Task (MET) - a unit that measures how much energy an activity consumes compared to being at rest. Find out more in our MET minutes calculator.
Patients self-report which activities they are able to do, and each activity is scored as such:
Are you able to: | Yes | No |
|---|---|---|
Take care of self (e.g. eating, dressing) | + 2.75 | 0 |
Walk indoors | + 1.75 | 0 |
Walk 1-2 blocks outdoors | + 2.75 | 0 |
Climb up a hill or stairs | + 5.5 | 0 |
Run a short ditance | + 8 | 0 |
Perform light housework (e.g. dusting) | + 2.7 | 0 |
Perform moderate housework (e.g. vacuuming) | + 3.5 | 0 |
Perform heavy housework(e.g. moving furniture) | + 8 | 0 |
Do yardwork | + 4.5 | 0 |
Have sexual relations | + 5.25 | 0 |
Perform recreational activities (e.g. bowling) | + 6 | 0 |
Perform strenuous sports (e.g. swimming) | + 7.5 | 0 |
DASI score interpretation
The final score can range from 0 to 58.2 points, where the higher the score, the higher the patient's functional status.
After calculating the final DASI score, the VO2 max and metabolic equivalent of task can be estimated as follow:
VO2 max (mL/kg) = 0.43 × DASI + 9.6
METs = VO2 max/ 3.5
In a study investigating the correlation of DASI scores with postoperative death or complications, a DASI score of 34 or less meant that a patient was at risk of:
- Myocardial injury;
- Myocardial infarction;
- Moderate-to-severe complications; and
- New disability in surgical patients.
Duke Activity Status Index calculator - a practical example
Let's try to estimate the Duke Activity Status Index for an exemplary patient using this DASI calculator.
- Our patient reports that he can perform most of the activities on the scale, except the most strenuous ones:
- He can't run;
- He can't perform heavy housework; and
- He can't do strenuous sports.
-
We need to add the points for all activities that our patient can do:
DASI score = 2.75 + 1.75 + 2.75 + 5.5 + 0 + 2.7 + 3.5 + 0 + 4.5 + 5.25 + 6 + 0
DASI score = 34.7
-
Now we can estimate:
a) peak VO2:
VO2 max (mL/kg) = 0.43 × DASI + 9.6
VO2 max (mL/kg) = 0.43 × 34.7 + 9.6
VO2 max (mL/kg) = 14.921 + 9.6
VO2 max (mL/kg) = 24.5
b) metabolic equivalents:
METs = VO2 max (mL/kg)/ 3.5
METs = 24.5/ 3.5
METs = 7