A MEDICAL CAUSE OF DEATH VALIDATION-STUDY OF ADULT ABORIGINAL DEATHS IN THE NORTHERN-TERRITORY OF AUSTRALIA IN 1992

Judged on the criterion of equity, premature adult Aboriginal mortalit y is the most serious public health problem faced in Australia today. There have been a number of published epidemiological studies that hav e analysed Aboriginal cause of death data, but this is the first study to formally validate such data. The study sample included all adult A boriginal people who lived and died in the Northern Territory in 1992, excluding residents of the Alice Springs region. The appropriateness of underlying cause of death codes was assessed by a single reviewer i n light of death certificates, medical records, postmortem records and interviews with key health professional informants. Data were collect ed on 220 deaths. 8% (17 out of 220) of deaths were classified erroneo usly at the ICD-9 chapter level. Errors in death certification account ed for 64% (11 out of 17) of the chapter errors and diagnostic and cod ing errors for 18% (3 out of 17) each. The overall impact on mortality statistics was less severe because some cross-chapter classification errors cancelled each other out. Misclassification errors aggregated m ainly in chapter VII (circulatory diseases) of the ICD-9 classificatio n which was overcounted by 3.2%, and chapter VIII (respiratory disease s) which was overcounted by 1.3%. Before correction for misclassificat ion error, circulatory diseases were judged to cause the highest propo rtion of deaths, whereas after correction, respiratory diseases accoun ted for the highest proportion. Despite this, the overall quality of t he medical cause of death statistics was of a sufficiently good standa rd from a public health perspective to broadly inform health policy. F uture attempts to improve the validity of medical cause of death stati stics for Australian Aboriginal people should focus on the education o f medical practitioners about the purpose and process of death certifi cation.