Comparing Swedish hospital discharge records with death certificates

Department of Public Health and Caring Sciences, Uppsala University, Uppsala, Uppsala, Sweden
International Journal of Epidemiology (Impact Factor: 9.18). 07/2000; 29(3):495-502. DOI: 10.1093/ije/29.3.495
Source: PubMed


The quality of mortality statistics is of crucial importance to epidemiological research. Traditional editing techniques used by statistical offices capture only obvious errors in death certification. In this study we match Swedish hospital discharge data to death certificates and discuss the implications for mortality statistics.
Swedish death certificates for 1995 were linked to the national hospital discharge register. The resulting database comprised 69 818 individuals (75% of all deaths), 39 872 (43%) of whom died in hospital. The diagnostic statements were compared at Basic Tabulation List level.
The last main diagnosis and the underlying cause of death agreed in 46% of cases. Agreement decreased rapidly after discharge. For hospital deaths, the main diagnosis was reported on 83% of the certificates, but only on 46% of certificates for non-hospital deaths. Malignant neoplasms and other dramatic conditions showed the best agreement and were often reported as underlying causes. Conditions that might follow from some other disease were often reported as contributory causes, while symptomatic and some chronic conditions were often omitted. In 13% of cases, an ill-defined main condition was replaced by a more specific cause of death.
There is no apparent reason to question the death certificate if the main diagnosis and underlying cause agree, or if the main diagnosis is a probable complication of the stated underlying cause. However, cases in which the main diagnosis cannot be considered a complication of the reported underlying cause should be investigated, and assessments made of the feasibility and cost-effectiveness of routinely linking hospital records to death certificates.

    • "All physicians and pathologists are obliged to report all cancer cases, and the register has been verified to have 98% nationwide completeness in terms of EAC [17]. The Swedish Causes of Death Registry contains data regarding all deceased Swedish residents since 1952 and has a 99.2% completeness of cause-specific death [18]. Data from this register were used to censor individuals in the cohorts from follow-up at the date of death. "
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    • "The distribution of consistency and independence according to socio-demographic and medico-administrative variables gave expectable results: independence was more frequent in elder patients, likely because they suffer from multi-pathologies, or as the discharge-death time interval grew (8.5% of in-hospital deaths, 14.3% when death occurred within one month after discharge and 27.7% within 6 to 12 months), or for non-neoplasms UCDs, which had already been noted in former studies [5,6,8]. "
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    • "• Deaths from the Causes of Death Register (The National Board of Health and Welfare) which comprises all deaths since 1961 and is updated every year. The register covers all Swedish residents, whether the person in question was a Swedish citizen or not, and irrespective of whether the death occurred in Sweden or not [24] [25]. • The Prescribed Drug Register (The National Board of Health and Welfare) contains complete data on all prescription drugs dispensed in Sweden from July 2005 onwards, their amounts and dosages, as well as expenditures and reimbursement, and the age and gender of the patient regardless of reimbursement status, co-payment and prescriber category [26]. "
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