CAISS Injury Severity Scoring 4 — Questions and Answers
Question 1: Which of the following is a recognized limitation of the standard ISS?
- It cannot be applied to blunt trauma
- Multiple serious injuries in the same body region may be underrepresented (Correct answer)
- It requires physiologic data to calculate
- It cannot exceed a score of 50
Correct answer: Multiple serious injuries in the same body region may be underrepresented
Because ISS uses only one injury per region, a patient with two AIS 5 chest injuries is scored the same as one with a single AIS 5 chest injury.
Question 2: Which AIS edition introduced standardized crash pulse and biomechanical coding?
- AIS-80
- AIS-90
- AIS-2005 Update 2008 (Correct answer)
- AIS-2015
Correct answer: AIS-2005 Update 2008
AIS-2005 Update 2008 included refinements to vehicle crash coding and biomechanical injury descriptors.
Question 3: For the ISS, which body region captures injuries to the skin and soft tissue without underlying organ damage?
- Abdomen
- Extremities
- External (Correct answer)
- Face
Correct answer: External
The External region covers skin lacerations, burns, and superficial soft-tissue injuries not assigned to other regions.
Question 4: A patient with AIS scores of 5 (head), 3 (chest), and 1 (extremity) has an ISS of:
- 25
- 34
- 35 (Correct answer)
- 59
Correct answer: 35
ISS = 5² + 3² + 1² = 25 + 9 + 1 = 35.
Question 5: The Abbreviated Injury Scale uses which coding structure to identify specific injuries?
- ICD-10 alphanumeric codes
- A seven-digit numeric code (Correct answer)
- A four-character alphanumeric descriptor
- Free-text narrative only
Correct answer: A seven-digit numeric code
Each AIS injury is assigned a unique seven-digit numeric code that specifies body region, type, and severity.
Question 6: Penetrating trauma ISS is typically analyzed separately from blunt trauma ISS because:
- Penetrating injuries cannot be coded in AIS
- Mechanism of injury affects the relationship between ISS and mortality (Correct answer)
- ISS is not valid above 25 for penetrating trauma
- Penetrating injuries are always coded AIS 6
Correct answer: Mechanism of injury affects the relationship between ISS and mortality
For a given ISS, penetrating trauma often has different mortality risk than blunt trauma, so TRISS uses separate regression coefficients for each mechanism.
Question 7: In pediatric trauma, which scoring system adjusts ISS norms for age-related physiologic differences?
- Pediatric Trauma Score (PTS) (Correct answer)
- ISS-Pediatric (ISSP)
- Modified ISS (MISS)
- CRAMS Scale
Correct answer: Pediatric Trauma Score (PTS)
The Pediatric Trauma Score incorporates weight, airway, blood pressure, CNS status, skeletal, and cutaneous components to reflect pediatric physiology.
CAISS Injury Severity Scoring 4
Which of the following is a recognized limitation of the standard ISS?