This calculator is for general information and education. It is not medical advice and does not replace the judgment of a doctor, nurse or pharmacist who knows the full clinical picture.
Measuring fitness with 12 questions
Functional capacity, how much physical effort you can sustain, is a strong predictor of how well people tolerate major surgery and of long-term heart health. It is best measured with a treadmill or cycle test with gas analysis, but such tests take time and equipment. The Duke Activity Status Index (DASI), published by Mark Hlatky and colleagues in 1989, estimates it from 12 simple questions about everyday activities.
The questions and their weights
| Activity | Points |
|---|---|
| take care of yourself (eat, dress, bathe, use the toilet) | 2.75 |
| walk indoors | 1.75 |
| walk a block or two on level ground | 2.75 |
| climb a flight of stairs or walk up a hill | 5.50 |
| run a short distance | 8.00 |
| light housework (dusting, dishes) | 2.70 |
| moderate housework (vacuuming, carrying groceries) | 3.50 |
| heavy housework (scrubbing floors, moving furniture) | 8.00 |
| yard work (raking, weeding, mowing) | 4.50 |
| sexual relations | 5.25 |
| moderate recreation (golf, bowling, dancing, doubles tennis) | 6.00 |
| strenuous sports (swimming, singles tennis, basketball, skiing) | 7.50 |
The total ranges from 0 to 58.2.
From DASI to METs
The original study compared answers with measured oxygen uptake and found:
Peak VO₂ (mL/kg/min) = 0.43 × DASI + 9.6
One MET, the energy used at rest, corresponds to 3.5 mL/kg/min, so METs = VO₂ ÷ 3.5.
Example
Someone who can look after themselves, walk, climb stairs, do light and moderate housework and yard work, and have sex, but not run, do heavy housework or play sports, scores 28.7. That gives an estimated VO₂ of 21.9 mL/kg/min, or 6.3 METs.
Before surgery
Guidelines on noncardiac surgery have long used the ability to perform 4 METs of activity, such as climbing two flights of stairs, as a sign that further heart testing is rarely needed. The international METS study, published in 2018, found that the DASI predicted complications better than doctors’ subjective estimate of fitness, and a later analysis linked scores of 34 or less to a higher risk of death or heart attack within 30 days.
Limits
The DASI relies on what you report, and people may over- or underestimate what they can do. Joint pain, lung disease or simple lack of opportunity can limit activities without heart disease. It is a screening tool, not a substitute for a medical assessment or exercise test.