🏋️ DASI Calculator
Duke Activity Status Index — Assess functional capacity using a 12-item questionnaire to estimate VO₂ max and METs.
What is DASI?
The Duke Activity Status Index (DASI) is a self-administered 12-item questionnaire developed by Mark Hlatky and colleagues at Duke University in 1989. It provides a quick and practical way to assess a patient's functional capacity — their ability to perform common daily activities that require varying levels of physical exertion.
DASI is widely used in clinical settings to:
- Estimate cardiovascular fitness without exercise testing
- Evaluate preoperative risk for non-cardiac surgery
- Track changes in functional status over time
- Guide decisions about further cardiac evaluation
Understanding METs
MET (Metabolic Equivalent of Task) is a unit used to express the energy cost of physical activities. One MET equals the oxygen consumption at rest, approximately 3.5 mL O₂/kg/min.
1 MET = Sitting quietly (3.5 mL O₂/kg/min)
4 METs = Climbing a flight of stairs, walking up a hill
8 METs = Running a short distance, heavy housework
10+ METs = Strenuous sports like swimming or singles tennis
A functional capacity of ≥ 4 METs is generally considered adequate for most surgical procedures. Patients who cannot achieve 4 METs have been shown to have significantly higher rates of perioperative complications.
The 12 DASI Activities
| # | Activity | Weight |
|---|---|---|
| 1 | Self-care (eating, dressing, bathing) | 2.75 |
| 2 | Walk indoors | 1.75 |
| 3 | Walk 1–2 blocks on level ground | 2.75 |
| 4 | Climb stairs or walk up a hill | 5.50 |
| 5 | Run a short distance | 8.00 |
| 6 | Light housework | 2.70 |
| 7 | Moderate housework | 3.50 |
| 8 | Heavy housework | 8.00 |
| 9 | Yardwork | 4.50 |
| 10 | Sexual relations | 5.25 |
| 11 | Moderate recreational activities | 6.00 |
| 12 | Strenuous sports | 7.50 |
The maximum possible score is 58.20 (all activities answered "Yes").
How is the Score Calculated?
DASI Score = Sum of weights for all "Yes" answers (range: 0–58.2)
VO₂ max (mL/kg) = 0.43 × DASI + 9.6
METs = VO₂ max ÷ 3.5
Example Calculation
If a patient can perform self-care (2.75), walk indoors (1.75), walk 1–2 blocks (2.75), and do light housework (2.70):
- DASI Score = 2.75 + 1.75 + 2.75 + 2.70 = 9.95
- VO₂ max = 0.43 × 9.95 + 9.6 = 13.88 mL/kg
- METs = 13.88 ÷ 3.5 = 3.97 METs
Clinical Significance
The MEASURE trial (2020) established DASI as a validated preoperative assessment tool. Key findings include:
- Patients with DASI ≤ 34 had significantly higher rates of postoperative myocardial injury and 30-day death or MI
- DASI was a better predictor of outcomes than subjective physician assessment
- A DASI score ≤ 34 identifies patients who may benefit from further preoperative cardiac evaluation
How to Use This Calculator
- Review each of the 12 activities listed
- Check the box for each activity the patient can perform
- Click "Calculate DASI Score"
- Review the DASI score, estimated VO₂ max, METs, and risk interpretation
The weight badge next to each activity shows how many points that activity contributes to the total score.
Limitations
- DASI is a self-reported measure and may be affected by patient perception or motivation
- It does not replace formal exercise stress testing when clinically indicated
- Cultural and environmental factors may affect a patient's ability to perform certain activities
- Some activities may not be applicable to all patients (consider "not applicable" as "No")
⚠️ Disclaimer: This calculator is for educational and screening purposes. Clinical decisions about preoperative evaluation should involve a qualified healthcare provider.