ABSI – Abbreviated Burn Severity Index
Predicts burn survival using sex, age, inhalation injury, full-thickness burn, and %TBSA burned
For use by health professionals only. The ABSI score provides approximate, population-level mortality risk estimates derived from historical cohorts. Modern burn care often achieves better outcomes. ABSI must not be used alone to limit or withdraw treatment for an individual patient.
Enter patient and burn details
Factor points:
• Sex: – |
Age: – |
Inhalation: – |
Full-thickness: – |
TBSA: –
Total ABSI score: –
Risk band: Not yet calculated
Enter all fields above, then click “Calculate ABSI” to see the total score and an approximate mortality risk band based on the original ABSI model.
Point scheme (classical ABSI): female sex = 1 point (male = 0); age: 0–20 = 1, 21–40 = 2, 41–60 = 3, 61–80 = 4, 81–100 = 5; inhalation injury present = 1; full-thickness burn present = 1; TBSA: 1–10 = 1, 11–20 = 2, 21–30 = 3, 31–40 = 4, 41–50 = 5, 51–60 = 6, 61–70 = 7, 71–80 = 8, 81–90 = 9, 91–100 = 10. Higher ABSI scores correspond to higher mortality in multiple validation studies; however, contemporary survival is often better than originally reported.
The Abbreviated Burn Severity Index (ABSI) is a burn-specific prognostic score that estimates a patient’s chance of survival after an acute burn injury. It was first proposed by Tobiasen et al. in 1982 and remains one of the most widely used burn mortality scoring systems worldwide. J Clinical Medicine Surgery
ABSI is attractive because it uses five simple clinical factors, all available at first assessment:
- Sex
- Age
- Inhalation injury (present/absent)
- Full-thickness burn (present/absent)
- % Total Body Surface Area (TBSA) burned
Each factor is converted into points, which are summed to give a total ABSI score (typically from 2 to ~15). Higher scores indicate higher mortality risk.
How the ABSI score is constructed
Commonly used point scheme (original Tobiasen model):
- Sex
- Male = 0
- Female = 1
- Age (years)
- 0–20 = 1 point
- 21–40 = 2 points
- 41–60 = 3 points
- 61–80 = 4 points
- 81–100 = 5 points
- Inhalation injury
- No = 0 points
- Yes = 1 point
- Full-thickness burn (3rd degree)
- No = 0 points
- Yes = 1 point
- %TBSA burned
- 1–10% = 1 point
- 11–20% = 2 points
- 21–30% = 3 points
- 31–40% = 4 points
- 41–50% = 5 points
- 51–60% = 6 points
- 61–70% = 7 points
- 71–80% = 8 points
- 81–90% = 9 points
- 91–100% = 10 points
The total ABSI is the sum of all these points. Higher ABSI has been consistently associated with higher mortality across many cohorts and meta-analyses. journals.plos.org
Interpretation (very approximate)
Original work related ABSI ranges to expected survival; later studies confirm that mortality rises steeply with higher scores, although modern burn units now often achieve better survival than the original tables predicted. J Clinical Medicine Surgery
A commonly used interpretation (based on original ABSI survival bands, expressed here as risk bands, not exact percentages):
- ABSI 2–3 – Very low mortality risk (survival ≈ ≥99%)
- ABSI 4–5 – Low risk
- ABSI 6–7 – Moderate risk
- ABSI 8–9 – High risk
- ABSI 10–11 – Very high risk
- ABSI ≥12 – Extremely high risk
Important: ABSI is a population-level prognostic tool for counselling, triage and audit, not a stand-alone decision tool for futility or treatment limitation in an individual patient.
