Injury Severity Score Calculator
Calculate ISS to assess trauma severity using the Abbreviated Injury Scale (AIS)
Calculate Injury Severity Score (ISS)
Example Calculation
Motor Vehicle Accident Patient
Injury Assessment:
• Head & Neck: No injury (AIS 0)
• Face: Minor laceration (AIS 1)
• Chest: Moderate pneumothorax (AIS 2)
• Abdomen: Serious liver injury (AIS 3)
• Extremity: No injury (AIS 0)
• External: No injury (AIS 0)
ISS Calculation
Three highest AIS scores: 3, 2, 1
ISS = 3² + 2² + 1² = 9 + 4 + 1 = 14
ISS Score: 14 (Moderate trauma)
ISS Score Ranges
Minor
Low mortality risk
Moderate
Increased mortality
Severe
High mortality risk
Very Severe
Very high mortality
Quick Reference
ISS ≥ 16: Major trauma
Any AIS 6: ISS = 75 automatically
Uses 3 highest AIS scores
Correlates with mortality
Medical Disclaimer: This calculator is for educational purposes only and should not replace professional medical assessment. The Injury Severity Score should be calculated by trained healthcare professionals using complete clinical information. Always consult with medical professionals for clinical decisions. In emergency situations, seek immediate medical attention.
Understanding the Injury Severity Score
What is the ISS?
The Injury Severity Score (ISS) was developed by Baker and colleagues in 1974. It's an anatomical scoring system that provides an overall score for patients with multiple injuries by incorporating the three most severely injured body regions.
Clinical Applications
- •Trauma severity assessment
- •Mortality prediction
- •Resource allocation
- •Research and quality improvement
- •Defining "major trauma" (ISS > 15)
How ISS is Calculated
Step 1: AIS Scoring
Each of the 6 body regions is scored using the Abbreviated Injury Scale (AIS) from 0 (no injury) to 6 (unsurvivable).
Step 2: Select Top 3
Identify the three body regions with the highest AIS scores.
Step 3: Calculate ISS
ISS = (highest AIS)² + (2nd highest AIS)² + (3rd highest AIS)²
Special Rule: If any region has AIS = 6, ISS is automatically 75.
Body Regions in ISS
Head & Neck
Includes brain, skull, cervical spine, and associated structures
Face
Facial skeleton, nose, mouth, eyes, ears, and related structures
Chest
Thoracic contents, thoracic spine, and diaphragm
Abdomen
Abdominal organs, lumbar spine, and pelvic contents
Extremities
Arms, legs, pelvic girdle, and bony pelvis
External
Skin, subcutaneous tissue, and external structures