Counting in-hospital deaths in England: a comparison of hospital computer systems and mortuary registers

Abstract

Objectives: In-hospital death counts derived from hospital computer systems have been used in England by an independent company, 'Dr Foster', to rank the quality of care of hospitals, but the validity of the underlying data remains unclear. This study compares counts of in-hospital deaths using two different sources - the hospital computer system and the mortuary register - to determine: whether the counts of in-hospital deaths from these two sources differed; qualitative explanations for possible sources of discrepancy; the direction and magnitude of any differences; and the possible impact of any differences on the Dr Foster rankings.

Methods: The four highest and the four lowest National Health Service (NHS) hospitals in the West Midlands, as ranked by Dr Foster, participated. Each hospital was asked to compare the monthly counts of in-hospital deaths from the hospital computer system and the hospital mortuary register for the fiscal year 1999/2000.

Results: One hospital, with a computerised mortuary register, had identical counts of in-hospital deaths. Two hospitals reported 4-5% more deaths and four hospitals reported fewer deaths (0.4-7%) from their hospital computer system than from their mortuary register. These differences were not large enough to change their Dr Foster rankings. Wide discrepancies were noted on a monthly basis (range: -13.9% to +15.9%).

Discussion: The differences between the two sources of in-hospital death counts were not large enough to influence the Dr Foster ranks but were sufficient to raise concern about the validity and completeness of mortality data in the NHS.