ASA Physical Status: ASA Physical Status Classification

What is ASA Physical Status?

ASA Physical Status (ASA Physical Status Classification) is a validated clinical instrument used to assess pre-operative health status. The instrument contains 1 item.

Source / attribution: American Society of Anesthesiologists, 2020 update

Clinical context: when ASA Physical Status is used

The instrument's primary construct — pre-operative health status — is operationalized through a fixed set of items, each with a defined response format. This standardisation is what allows ASA Physical Status scores to be compared meaningfully across clinicians, sites, and studies.

Like all screening or assessment instruments, ASA Physical Status is a structured aid — not a diagnostic test in isolation. Results should be interpreted alongside history, examination, and clinical context. Where a score crosses an actionable threshold, the next step is typically a more detailed clinical evaluation rather than a definitive diagnosis.

Score ASA Physical Status

Each item is scored on a 6-point scale (1–6). Your score updates live as you answer.

All scoring runs in your browser. No data is sent anywhere — close the tab and the answers are gone.

How ASA Physical Status is scored

ASA Physical Status uses simple summation: each item's selected response is converted to a numeric value, and the values are added to produce a total score. Reverse-scored items are inverted before summation.

Scoring notes: Educational use only.

ASA Physical Status score interpretation

The cutoffs below are drawn from the published validation literature. Always interpret in clinical context.

How to score ASA Physical Status: a step-by-step worked example

This is an illustrative walkthrough, not a real patient. Follow the same four steps with your own answers — or use the live calculator at the top of this page.

Step 1 — Score each item

Read each question and choose the response that best fits. Each response has a number next to it — that number is the item's score. The example below uses illustrative answers.

Step 2 — Add up the scores

Add up all the item scores you noted in Step 1.

4 = 4

Step 3 — Look up the band

Find the row in the interpretation table whose range contains your total:

Total = 4 falls between 4 and 4 → Class IV

Step 4 — What does this mean clinically?

Class IV. Life-threatening.

A score is one input alongside history and examination. ASA Physical Status supports clinical judgment — it does not replace it.

Score ASA Physical Status with your own answers above →

Limitations & common pitfalls

• Educational use only.
• Screening, not diagnosis. A positive ASA Physical Status score is not equivalent to a diagnosis. Confirmatory clinical evaluation is required before treatment decisions.
• Population calibration. Cutoffs were derived from specific validation populations. Performance can differ in other age groups, languages, comorbid conditions, or clinical settings.
• Self-report bias. Patient-reported instruments are subject to under- and over-reporting; clinical context is essential.

How ASA Physical Status compares to other anesthesia scales

If ASA Physical Status doesn't fit your context, related instruments in anesthesia include:

Frequently asked questions about ASA Physical Status

References & validation

ASA Physical Status is supported by the following peer-reviewed sources:

• ASA Physical Status Classification System. American Society of Anesthesiologists; updated 2020.