1. The Problem with KSI: Using Trauma Data to Analyse Injury Severity
Matt Staton
Cambridgeshire County Council
Road Safety GB Analysis Conference - Joining the Dots 2 March 2017

2. Overview Understanding Major Trauma Different severity definitions
What can we learn from it?

3. The 4th ‘E’
Engineering
Education (ETP)
Enforcement
Epidemiology

4. East of England Trauma Network
Trauma System
East of England Trauma Network

5. Trauma
Fatal injuries
Injuries requiring hospitalisation or resulting in disability
Injuries treated in emergency department setting
Injuries treated in primary care setting
Injuries that do not receive attention in a healthcare setting

6. Trauma System Epidemiology Population based
Multi-agency Injury Research Register (5 years)
100% case ascertainment
Complete epidemiological description
Mechanism
Injury patterns
Pre-hospital care
Emergency care
Outcomes (pre-hospital and in-hospital)
Socio-demographic profile
Cambridgeshire Trauma Audit
and Research Project

7. Do not meet entry criteria
CTARP Data
39,763
STATS 19
Persons
‘injured’
2,850
ONS
Registered
deaths
3,307
PHEMS
Attended
patients
3,383
TARN
Submitted
cases
254
Pre-hospital
deaths
983
Survivors to hospital
38,526
Do not meet entry criteria
1,237
Meet entry criteria
2,020
1,363
2,682
625
186
439
2,464
261
123
384
329
1,685
150
In-hospital
deaths
Entry criteria: Kinetic injury event within the geographical County of Cambridgeshire between 2000 and 2004 and resulting in a pre-hospital trauma death (with injuries which would have met TARN injury criteria) or survival to hospital with admission that met TARN 07 entry criteria
Cambridgeshire Trauma Audit
and Research Project

8. CTARP Data Pre-hospital Deaths - 329 ONS STATS19 PHEMS
(261)
STATS19
(254)
PHEMS
(186)
Entry criteria: Kinetic injury event within the geographical County of Cambridgeshire between 2000 and 2004 and resulting in a pre-hospital trauma death (with injuries which would have met TARN injury criteria) or survival to hospital with admission that met TARN 07 entry criteria
Cambridgeshire Trauma Audit
and Research Project

9. CTARP Data Survivors to hospital - 1685 Cambridgeshire Trauma Audit
ONS
(123) 35 21 1 2 20
PHEMS
(439) 21
TARN
(1363) 15 8 1
592 50
271
386 85
177
STATS 19
(983)
Entry criteria: Kinetic injury event within the geographical County of Cambridgeshire between 2000 and 2004 and resulting in a pre-hospital trauma death (with injuries which would have met TARN injury criteria) or survival to hospital with admission that met TARN 07 entry criteria
Cambridgeshire Trauma Audit
and Research Project

10. Epidemiology Burden of Disease (Count of patients, 95% CI)1
Pre-hospital System
Survive to hospital
Admitted with significant injury
(meeting UK TARN entry criteria) 2
Age-standardised population rate per 100,000 (95% CI) 3
999
Call
2623 4
Serious injury 55
(53-57)
Survival to hospital 46
(42-48)
Serious
Injury 34
(32-36)
Severe Injury
(ISS >8) 22
(20-23)
Major Trauma
(ISS > 15) 12
(11-13)
Cambridgeshire Trauma and Research Project
See
Directly age-standardised rate per 100,000 resident population with 95% confidence interval
Based on estimate from Ambulance Service related to 999 call burden for trauma related AMPDS codes (150000/year)

11. Epidemiology 12 (11 to 13 ) 22 (20 to 23 ) 34 (32 to 36)
EoE ITSPB
20 April 2010
Epidemiology
Major Trauma ISS > 15
‘Severe’ Injury ISS > 8
TARN entry criteria
12 (11 to 13 )
22 (20 to 23 )
34 (32 to 36)
Age-standardised population rate per 100,000 (95% CI)
R Mackenzie 11

12. Epidemiology
Road traffic collisions remain the commonest cause of severe injury or life threatening major trauma

13. STATS19 ‘serious injury’
Serious injury: An injury for which a person is detained in hospital as an “in-patient”, or any of the following injuries whether or not they are detained in hospital: fractures, concussion, internal injuries, crushings, burns (excluding friction burns), severe cuts, severe general shock requiring medical treatment and injuries causing death 30 or more days after the accident. An injured casualty is recorded as seriously or slightly injured by the police on the basis of information available within a short time of the accident. This generally will not reflect the results of a medical examination, but may be influenced according to whether the casualty is hospitalised or not. Hospitalisation procedures will vary regionally.

14. Trauma Network injury severity
Injury Severity Score (ISS)
Worst 3 injuries to 6 body regions using the Abbreviated Injury Scale (AIS)
Top 3 scores are squared and added together
Score >8 – severe injury
Score >15 – major trauma
Injury severity
Example
AIS code
Minor
Minor laceration 1
Moderate
Simple rib/sternal fracture 2
Serious
Open long bone fracture 3
Severe
Limb amputation 4
Critical
Spine injury with quadriplegia 5
Maximum
Total severance of aorta 6

15. CTARP ‘KSI’ Data 39,763 persons STATS19 persons
(from 17,256 incidents)
STATS19 persons
Five years to 2004 inclusive
15,897 uninjured and 1 unborn child excluded
23,865 persons
334 ‘killed’
2924 ‘serious’
20,594 ‘slight’
1064 discharged from ED
254 STATS19 pre-hospital deaths
(172 resident, 82 non-resident)
80 STATS19
in-hospital deaths (<30 days)
(64 resident, 16 non-resident)
1860
1019 with LoS < 72 hrs and/or injuries which do not meet CTARP/TARN entry criteria
841 ‘serious’
+ 2 in-hospital STATS19 death initially coded as serious and slight
(both resident)
62 met TARN entry criteria, 1 of which was an in-hospital death
+ 61 patients coded as slight
-1 of which is in-hospital death
336 ‘killed’
(238 resident / 98 non-resident)```````
901 ‘severe’
TARN entry criteria
(697 resident / 286 non-resident)
Cambridgeshire Trauma Audit
and Research Project
2083 ‘serious’
(1548 resident /
536 non-resident)
20,532
‘slight’

16. CTARP ‘KSI’ Data
Cambridgeshire Trauma Audit
and Research Project

17. CTARP Responsibility Data
All
persons
Cambridgeshire Trauma Audit
and Research Project

18. CTARP Responsibility Data
Responsible
persons
Cambridgeshire Trauma Audit
and Research Project

19. CTARP Responsibility Data
To blame (n=123)
Whole group (n= 281)
Significance (p)
Median age (IQR)
35 (22-49)
34 (22-49)
p=0.9
Mean Age (SD)
38 (20-58)
38 (19-57)
Modal Age 30 18
P=0.02
Proportion male (%) 76 47
P=0.005
43% of those with ISS>15 following road traffic collisions were not responsible for the injury event
Injury prevention strategies targeted according to the epidemiology of the injured may not effectively target those who cause injury events
Cambridgeshire Trauma Audit
and Research Project

20. Trauma System Lessons Learned
Multi-agency data sharing improves understanding
‘Serious injury’ in STATS19 terms doesn’t necessarily constitute a ‘severe injury’ in trauma care or injury prevention terms
Linking TARN and STATS19 data will provide the cheapest, quickest and most comprehensive understanding of road traffic related injury.
Existing prevention strategies, if targeted on injured road user profiles, may not be effectively targeted at high-risk or culpable road users.
Cambridgeshire Trauma Audit
and Research Project

21. We need to act on these lessons…
Engineering
Education (ETP)
Enforcement
Epidemiology

22. Contact
@statonmatt