When gastrointestinal diseases are certified as causes of death, they are often not selected as the underlying cause.
Until recently, only one underlying cause of death has been coded, and analyzed in official national statistics in England, and many other countries.
|Underlying-cause-coded mortality identified 47% of Crohn's disease|
|European Journal of Gastroenterology & Hepatology|
Dr Michael Goldacre and colleagues reported on the total burden of mortality from some common gastrointestinal diseases.
The research team also investigated whether the total burden of mortality has changed over time, including all certified causes of death as well as underlying causes.
The researchers examined the Oxford region from 1979 to 2003, and in England from 1996 to 2003.
The team quantified the under-ascertainment of cause-specific mortality when based on underlying cause alone.
The team recorded death certificate data from the Oxford Record Linkage Study database, and used English national data.
The researchers searched for specified gastrointestinal diseases certified as underlying or contributory causes of death.
The researchers found that for all the conditions studied, underlying-cause-coded mortality missed a substantial percentage of all certified deaths.
The extent of underestimation varied according to the periods in which different criteria were used for the selection of the underlying cause.
The team found that for example, in Oxford, in the latest period 1993 to 2003, underlying-cause-coded mortality identified only 37% of all death certificates with ulcerative colitis.Underlying-cause-coded mortality identified 47% of Crohn's disease, between 62% and 68% for the different types of peptic ulcer, and 66% of diverticular disease.
Dr Goldacres' team concluded, "Studies of mortality for these diseases should take account of all certified causes as well as underlying-cause mortality."
"This is particularly important for analyses that go across periods of change to the rules for selecting the underlying cause of death."