Calculator Input Form
Plotly Graph
The chart displays point contribution from each CHADS2 component.
Example Data Table
| Example Patient | Age | CHF | Hypertension | Diabetes | Prior Stroke/TIA | CHADS2 Score | Relative Risk Class |
|---|---|---|---|---|---|---|---|
| Patient A | 68 | No | Yes | No | No | 1 | Intermediate |
| Patient B | 79 | Yes | Yes | Yes | No | 4 | Higher |
| Patient C | 82 | No | No | No | Yes | 3 | Higher |
Formula Used
The CHADS2 score is a point-based stroke risk tool. Add 1 point each for congestive heart failure, hypertension, age 75 years or older, and diabetes mellitus. Add 2 points for previous stroke or transient ischemic attack.
| Component | Points |
|---|---|
| Congestive heart failure | 1 |
| Hypertension | 1 |
| Age 75 years or older | 1 |
| Diabetes mellitus | 1 |
| Prior stroke or TIA | 2 |
Formula: CHADS2 = CHF + HTN + Age≥75 + Diabetes + 2×(Prior Stroke or TIA)
How to Use This Calculator
- Enter the patient age.
- Select whether each CHADS2 risk factor is present.
- Add optional patient name and notes for report exports.
- Click the calculate button.
- Review the total score, factor breakdown, and relative risk category.
- Use the export buttons to save CSV or PDF output.
Important Note
This calculator is for educational and documentation support only. It does not replace clinician judgment, patient-specific evaluation, guideline review, or formal treatment decisions.
Frequently Asked Questions
1. What does the CHADS2 score estimate?
It estimates relative stroke risk using five clinical factors commonly reviewed in atrial fibrillation assessments. It is a simplified scoring approach, not a complete treatment recommendation.
2. Why does prior stroke or TIA count as two points?
Prior stroke or transient ischemic attack carries stronger clinical weight in the scoring model, so it contributes more to the final total than the other single-point variables.
3. Does age automatically add points?
Yes. Age adds one point when the patient is 75 years or older. Ages below 75 do not receive the age component point in CHADS2 scoring.
4. Is this the same as CHA₂DS₂-VASc?
No. CHADS2 is a simpler older framework. CHA₂DS₂-VASc includes additional variables and is often used when a more detailed risk stratification approach is needed.
5. Can this tool decide anticoagulation therapy?
No. Treatment decisions require broader clinical context, bleeding risk review, medication suitability, comorbidities, patient preferences, and current guideline-based assessment by a qualified clinician.
6. What does a higher CHADS2 score mean?
A higher score suggests greater relative stroke risk based on selected predictors. It signals the need for careful clinical review rather than acting as a standalone management instruction.
7. Why include CSV and PDF downloads?
Export options help save calculation details for charting support, review meetings, audits, patient discussions, or documentation workflows without re-entering the same information again.
8. Can I use this calculator on mobile devices?
Yes. The form uses a responsive grid that shows three columns on large screens, two on medium screens, and one column on smaller mobile displays.