CRICOS No J Dr Kirsten Vallmuur and Ms Jesani Limbong 11 th 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) InjuryDefinition MinorRequires first aid treatment; medical attention is not necessary ModerateAre temporary or remediable; Consequences are not life-threatening and are reversible in most instances. SeriousIrreversible; cause permanent disability or long-term illness DeathAny injuries resulting in death InjuryDefinition 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 typeRAPEXCanada Abrasion/ Bruising Internal bruising severeNever severe Burn/ScaldBurns to >16% body surface severe Burns to >10% body surface severe ConcussionProlonged unconsciousness severe Prolonged time for symptoms to resolve severe ElectricalOther serious effects (burns/cardiac effects etc) of electrical exposure severe Only electrocution severe FractureRib/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 StrangulationNever minor/moderateBruising/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 RANKRAPEXCanada 1 or Minor 1 st degree burns up to 100 % of body surface 2 nd degree < 6 % of body surface 1st degree burns 2 or Moderate 2 nd 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 2 nd degree burns at % of body surface 3 rd degree burns up to 35 % Inhalation burn 2nd degree burns up to >10% of the body or to the head 3 rd degree burns Any burn resulting in permanent disfigurement or severe scarring 4 or Death 2 nd or 3 rd degree > 35 % of body surface Inhalation burn requiring respiratory assistance Burn/scald resulting in death

Principal code: Burn Thickness ABCD UnspecifiedErythemaPartialFull 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 3 rd Ch T31.0 BSA Less than 10% or unspecified 0UnclassifiableBurn 1 Burn 1 Burn 2 Burn 3 2 T31.1 BSA 10-19% 1UnclassifiableBurn 1 Burn 2 Burn 3 3 T31.2 BSA 20-19% 2UnclassifiableBurn 1Burn 3 4 T31.3 BSA 30-39% 3UnclassifiableBurn 1 Burn 3 Burn 4 Burn 3 Burn 4 5 T31.4 BSA 40-49% 4UnclassifiableBurn 1Burn 4 6 T31.5 BSA 50-59% 5UnclassifiableBurn 1Burn 4 7 T31.6 BSA 60-69% 6UnclassifiableBurn 1Burn 4 8 T31.7 BSA 70-79% 7UnclassifiableBurn 1Burn 4 9 T31.8 BSA 80-89% 8UnclassifiableBurn 1Burn 4 10T31.9 BSA 90% or more 9UnclassifiableBurn 1Burn 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

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