# Presentation: 191220

## Multiple cause of death data and poisoning 

- Cleo Rooney &
- Multiple cause of injury workgroup
- April 2001

## Discussions

- Uses of multiple cause coded mortality data and selecting main injury
- explaining differences in underlying cause data
- between places, times
- ‘correcting’ unspecified underlying cause
- Difficulties classifying poisonings with multiple substances
- Changes in ICD-10 and comparability studies

## Main injury in mortality data

- Encourage publication of multiple cause data-  ~ 15 countries / 65 contribute data to WHO
- ICD-9 precedence list provided for choosing main injury
- Skull Fracture and broken neck
- Internal Injury of chest, abdomen, pelvis
- Fracture of face, spine, trunk
- Other head injury, open wounds of neck&chest, amputation of limbs,  spinal cord lesion
- Fracture of limbs
- Burn
- Other

## Main Injury in ICD-10

- ICD-10
- Sequence and rules provided as for other deaths
- If no sequence, choose first mentioned
- Combination codes could be selected
- Problems:
- In injury events there may not be a time sequence
- Do certifiers know sequence matters?
- Loss of specificity/detail if use combination code
- Selection rule is not WHO mandated

## Israel method of choosing main injury 

- Presented way of classifying injury morbidity data by severity (AIS), nature  and body region
- Allowed main / most serious injury selection for trauma registry / hospital admission
- Requires ICD codes and AIS scores
- ? use to test selection of main injury

## Number of injury codes per deathCox, Rooney, Fingerhut ICE 2000

## Proposed analyses of multicause 

- Compare main injury chosen by
- Precedence list
- First listed
- ICD-10 rules
- Combination codes
- Diagnostic matrix
- Redistribute ‘unspecified accident’ deaths using injury information

## Injury deaths of unspecified mechanism by ICD-9 main injury precedence list Cox, Rooney, Fingerhut ICE 2000

## Countries that submitted multicause data in ICD-9

- USA
- Sweden
- Scotland
- E&W
- More volunteers?

## Changes in coding injury deaths in ICD-10

- Main Injury
- No precedence list for injuries
- Combination codes for injuries
- Underlying cause
- Fracture unspecified cause > unspecified accident
- Fractures / falls can be due to osteoporosis
- Rule 3

## Comparability studies -multicountry

- Injury deaths ratios
- All injuries
- By matrix groups
- Differences between countires
- ?pooled ratios across countries
- Are ICD-10 data more comparable?
- Israel and US results yesterday-
- broadly reassuring

## Deaths from falls, fractures and osteoporosis

- Comparability ratios v different in USA, Israel and Sweden
- E887 > unspecified accident
- can be due to osteoporosis
- rule 3 and pneumonias
- Quantify net change by country
- ? Differences in each effect
- certification or coding

## Comparability study data

- Countries which can contribute
- Send copies of comparability study reports
- individual level data
- tabulated data / special analyses
- Volunteers?

## Poisonings

- c50% of deaths have more than one substance
- Can’t identify which of several substances primarily responsible for death
- combination codes may be confusing for data users
- need finer classification of substances
- meaningful classification for clinicians and toxicologists as well as epidemiologists

## Multi-substance poisonings

- Main injury and underlying cause
- combination codes
- Multicause codes
- Text of certificate
- more detail
- ?? How to present it

## Deaths from drugs and poisonings[poisonings 960-989, abuse & dep 304, 305]

- Number of deaths	alone		in combination
-    by substance
- all substances		x 		y
- heroin/morphine	A		B
- paracetamol		C		D
- antidepressants	E		F

## Projects for Montreal	

- Compare selection of main injury by different methods
- Redistribute unspecified accident deaths using injury codes
- Collate comparability study data ICD-9/ 10 across participating countries
- changes in classification of deaths from falls, fractures and osteoporosis
- ? Poisoning later ? volunteers