Assessment of accuracy of suicide mortality surveillance data in South Africa: investigation in an urban setting

Although it is not a legal requirement in South Africa, medical practitioners determine the manner of injury death for a surveillance system that is currently the only source of epidemiological data on suicide. This study assessed the accuracy of suicide data as recorded in the system using the docket produced from standard medico-legal investigation procedures as the gold standard. It was conducted in one of three cities where the surveillance system had full coverage for the year 2000. In the medico-legal system, one-third of cases could not be tracked, had not been finalized, or had unclear outcomes. For the remaining cases, the sensitivity, specificity, and positive and negative predictive values were generally high, varying somewhat across sex and race groups. Poisoning, jumping, and railway suicides were more likely than other methods to be misclassified, and were more common among females and Whites. The study provides encouraging results regarding the use of medical practitioner expertise for the accurate determination of suicide deaths. However, suicides may still be underestimated in this process given the challenge of tracing disguised suicides and without the careful examination of potential misclassifications of true suicides as unintentional deaths.