You asked
With reference to your published data titled 'Pre-existing conditions of People who died due to Covid-19, England and Wales, 2020' what is meant by; "3. Some deaths will be counted twice if there was more than one pre-existing condition, therefore the total number of deaths will be greater than the total number of deaths due to COVID-19." I would like to know how many cases have been counted twice? Does this effect the total number of Covid-19 deaths which currently stands at 125,445? Is the true number roughly half of this because many have been counted twice?
We said
Thank you for your request.
The Office for National Statistics provisional weekly deaths publication reports the number of death registrations where respiratory disease was recorded as the underlying cause. Respiratory disease is defined by the International Classification of Diseases, Tenth Revision (ICD-10) codes J00-J99 and includes influenza and pneumonia. COVID-19 is defined by the emergency ICD-10 codes U.701 and U.702.
Due to a difference in the way we report deaths for these cause groups, it is possible that some deaths are counted in both the respiratory and COVID-19 categories. This is because for respiratory disease we publish the number of deaths where it was recorded as the underlying cause only. This is compared to the number of deaths that 'involved' COVID-19 i.e. the number of deaths that mentioned COVID-19 anywhere on the death certificate, whether as the underlying cause or as a contributory factor. A death registration that has respiratory disease recorded as the underlying cause of death and COVID-19 recorded as a contributory factor would appear in both counts.
If COVID-19 was the underlying cause then it would be included in the COVID-19 category but not the respiratory disease underlying cause category. However, if COVID-19 was mentioned as a contributory factor and another type of respiratory disease was the underlying cause then the death would be counted in both the respiratory and COVID-19 categories.
It will not affect the total number of deaths as the deaths have not been double counted. It will just affect the pre-existing conditions categories total if they were summed.
If you would like to discuss this query further, please contact health.data@ons.gov.uk.