issues to consider when estimating injury severity … session 4 coding dr...cricos no. 00213j dr...

CRICOS No. 00213J

Dr Kirsten Vallmuur and Ms Jesani Limbong 11th October 2013

Issues to consider when estimating

injury severity during risk assessment

Focus of presentation

• Core input into risk assessment model is the

injury severity rank and probability of

occurrence

• Injury severity rank = Table of injury types and

body regions grouped into 4 or 6 point scale

• Core questions:

– How valid is the grouping of injuries?

– How consistent are these groupings across different

severity scales?

– How concordant are these groupings with other

indicators of injury severity?

Canada (Health Canada) Injury Definition

Minor Requires first aid treatment; medical attention is not necessary

Moderate Are temporary or remediable; Consequences are not life-threatening and

are reversible in most instances.

Serious Irreversible; cause permanent disability or long-term illness

Death Any injuries resulting in death

Injury Definition

1 Injury or consequence that after basic treatment (first aid, normally not by a doctor) does not

substantially hamper functioning or cause excessive pain; usually the consequences are completely reversible.

2 Injury or consequence for which a visit to A&E may be necessary, but in general, hospitalization is

not required. Functioning may be affected for a limited period, not more than about 6 months, and recovery is more

or less complete

3 Injury or consequence that normally requires hospitalisation and will affect functioning for more than 6

months or lead to a permanent loss of function.

4 Injury or consequence that is or could be fatal, including brain death; consequences that affect

reproduction or offspring; severe loss of limbs and/or function, leading to more than approximately 10 % of disability.

New Zealand

Europe/Australia (RAPEX Guidelines)

Injury severity ranking systems

Injury

Minor

Moderate

Serious

Severe

Critical

Death

Comparison of RAPEX and Canadian

Injury Severity Categorisation Injury type RAPEX Canada

Abrasion/

Bruising

Internal bruising severe Never severe

Burn/Scald Burns to >16% body surface

severe

Burns to >10% body surface

severe

Concussion Prolonged unconsciousness

severe

Prolonged time for symptoms

to resolve severe

Electrical Other serious effects

(burns/cardiac effects etc) of

electrical exposure severe

Only electrocution severe

Fracture Rib/jaw not severe;

Lower leg severe

Rib/jaw severe;

Lower leg not severe

Piercing/

Puncturing

Eye/internal organ/chest wall

severe

Eye/internal organ/chest wall

not severe

Strangulation Never minor/moderate Bruising/swallowing/

hoarseness not severe

Implications of Different Severity

Categorisation

• Injuries falling below the threshold may not be

raised to an investigation level in one jurisdiction

but may be in another -> inconsistent risk

prioritisation

• If injuries where differences exist are very

common, may lead to considerable discrepancy

(i.e. severity of different fractures)

• Explore injury data to get an indication of size of

problem and decide if better uniformity needed

Classifying injury data into

severity categories

• Injury severity ranks are largely based on injury

nature and body region

• Hospitalisation and mortality data have injury

diagnoses coded (codes structured into nature

of injury and body region codes)

• Assigning severity scores to injury data allows

for better illustration of severity by hazard and

product

Burns Severity Rank Comparisons

RANK RAPEX Canada

1 or

Minor

1st degree burns up to 100 %

of body surface

2nd degree < 6 % of body

surface

1st degree burns

2 or

Moderate 2nd degree burns at 6-15 % of

body surface

2nd degree burns up to ≤10% of the body

not including the head

Chemical burns causing reversible damage

3 or

Severe

2nd degree burns at 16-35 % of

body surface

3rd degree burns up to 35 %

Inhalation burn

2nd degree burns up to >10% of the body or

to the head

3rd degree burns

Any burn resulting in permanent

disfigurement or severe scarring

4 or

Death

2nd or 3rd degree > 35 % of

body surface

Inhalation burn requiring

respiratory assistance

Burn/scald resulting in death

Principal

code:

Burn

Thickness

A B C D

Unspecified Erythema Partial Full

T20.0, T21.0,

T22.0, T23.0,

T24.0 T25.0,

T29.0, T30.0

T20.1, T21.1,

T22.1, T23.1,

T24.1 T25.1,

T29.1, T30.1

T20.2, T21.2,

T22.2, T23.2,

T24.2 T25.2,

T29.2, T30.2

T20.3, T21.3,

T22.3, T23.3,

T24.3 T25.3,

T29.3, T30.3

Secondary code: Body

Surface Area

3rd Ch

3rd Ch 0 1 2 3

1 T31.0

BSA Less than 10% or

unspecified

0 Unclassifiable Burn 1 Burn 1

Burn 2 Burn 3

2 T31.1

BSA 10-19% 1 Unclassifiable Burn 1

Burn 2

Burn 3 Burn 3

3 T31.2

BSA 20-19% 2 Unclassifiable Burn 1 Burn 3 Burn 3

4 T31.3

BSA 30-39% 3 Unclassifiable Burn 1

Burn 3

Burn 4

Burn 3

Burn 4

5 T31.4


6 T31.5


7 T31.6


8 T31.7


9 T31.8


10 T31.9

BSA 90% or more 9 Unclassifiable Burn 1 Burn 4 Burn 4

Example categorisation of burns

data in Queensland children

Validating injury severity ranks

• Other health system-based injury severity scales:

– ICD-based Injury Severity Score (ICISS) => survival risk

ratio (SRR)

– Abbreviated injury score (AIS)

• Other indicators of severity:

– Triage urgency

– Emergency department presentation/ hospital

admission/mortality rates

– Length of stay

– Costs of treatment

– Disability outcomes

Next steps

• Compare injury data for the injuries where ranks

differ across injury severity systems

• Evaluate the validity of the ranks by comparison

with other health system-based injury severity

scales and with other severity indicators

• Revise and consolidate different injury severity

scales to establish a single international scale

for categorisation of injury severity

CRICOS No. 00213J

Questions? [email protected]

Reports:

http://eprints.qut.edu.au/46518/


mailto:[email protected]



issues to consider when estimating injury severity … session 4 coding dr...cricos no. 00213j dr...

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