The norwegian cause of death registry christian l.ellingsen

1. The Norwegian
Cause of Death Registry
Christian Lycke Ellingsen
2016

2. The Norwegian Cause of Death Registry
• 1951 ->: Electronic records, 2.6 mill deaths
• WHO classification (ICD)
• 1996: ICD-10
• 2005: ACME (semi-automatic identification of
underlying cause of death)
• 2002/2014: SN -> NIPH
• On the road towards e-certification

3. What happens in NCODR?
• Death certificates from the doctors
• Additional information
– Autopsy reports etc
• Quality control, queries
• Coding
• Data export
– Production of reports etc
– To researchers, health authorites etc

5. Core concepts

6. • A researcher must know a little about the logic in
identification the cause of death
• Cause-of-death sequence and classification
according to WHO (ICD-10)
• 10th revision, number 11 in the pipeline
• Systematic and hierarchic, 22 chapters
• More than 14.000 entities/codes
• Allows for international comparison

7. Underlying cause of death
• Underlying cause of death: The disease or
injury that initiated the train of morbid events
leading directly to death or the circumstances
of the accident or violence that produced the
injury.
If you ask for the cause of death, this is what
you get.

8. Immediate cause of death
• Immediate cause of death: The disease,
injury, or complication that directly results in
death, i.e., the ultimate consequence of the
underlying cause of death

9. Contributory cause of death
• Contributory cause of death: A significant
condition that unfavourably influences the
course of the morbid process and thus
contributes to the fatal outcome, but which is
not related to the disease or condition directly
causing death.

10. • Ia: Brain haemorrhage
due to
• Ib: Brain metastasis
due to
• Ic: Lung cancer
• II: Myocardial infarction
Immediate cause of death
Underlying cause of death
Contributory cause of death

11. The value of a register is not
better than the quality of its
data (but it can of course be even less useful).

12. The good
• A well characterised population
– Unique identification number allows for cross-
checking and register linkage
– Only 44% of births and deaths in the world
formally registered
• We do have death certificates…
– 2/3 of the deaths in the world are not medically
certified (WHO)

13. The bad
• Suboptimal quality of the death certificates
• We do not utilise all possibilities for quality
improvement
• International comparison: NCoDR usually
«medium-high quality»

14. Coverage
• 1-2 % missing death certificates
• Half of these are Norwegians dying abroad
• Total coverage good, but may be insufficient in
certain subgroups

15. We do not live in a perfect world
• Incomplete certificates
– “Detective work”, query letters
• Logical mistakes
– ICD rules, ACME
• Ill-defined codes (“garbage codes”)
– Where do they “belong”?
• Incorrect diagnoses
– Hard to amend without checking the hospital
records

17. For the researcher
• What data do I need? In which detail?
• Is NCoDR the right source?
• Is the quality good enough for me?
• Are there ways to validate the data?
• Record linkage?
• Do I want to consult with the people in NCoDR
about possibilities and pitfalls?

18. How to order data

19. • Forms at FHI web site www.fhi.no
• Fully anonymous data: No problem
• Data that may identify persons:
– Application to REK or Datatilsynet
• The same regulations for persons working
inside NIPH
• Call or e-mail us!

20. Example 1 – record linkage
• Conscription
examination data on
mental health function
from the Norwegian
Defence linked to data
on suicide and
unintentinal injuries
from NCoDR
• Unselected population
• Even those with minor
imparment had elevated
risk for dying

21. Example 2 – aggregated NCoDR data only
• Extreme geographical variation in the
frequency of forensic autopsies not explained
by variation in the causes of deaths
• Worrying
consequences for
the investigation of
unnatural deaths?

22. Some useful links
• https://www.fhi.no/hn/helseregistre-og-
biobanker/dodsarsaksregisteret/
• http://statistikkbank.fhi.no/dar/
• https://www.fhi.no/div/forskning-og-
datatilgang/
• http://apps.who.int/classifications/icd10/bro
wse/2016/en