A post-mortem survey on end-of-life decisions using a representative sample of death certificates: a research protocol for a study in Flanders and Brussels, Belgium.

Background
Reliable studies on incidence and characteristics of medical end-of-life decisions with a certain or possible life shortening effect (ELDs) are indispensable for an evidence-based medical and societal debate on this issue. However, these studies face several methodological difficulties. This presentation outlines how the protocol drafted for the 2007 ELD Study in Flanders and Brussels, Belgium, addresses these difficulties.

Method
Several methodological requirements guided the drafting of the protocol. The main aim of the study was to make reliable incidence estimates of ELDs, even of rare ELDs. Comparability with past ELD studies was favorable. Given the sensitive nature of the research topic, strict anonymity had to be guaranteed, and special attention had to be paid to a sufficient response rate.

Results
Reliable incidence estimates were possible by using large at random samples of death certificates of deceased persons in Flanders and Brussels. This needed the cooperation of the appropriate authorities. To obtain reliable estimates for less prevalent ELDs, a stratified sample was used. Questionnaires were sent out to the certifying physician of each included death. The questionnaire was largely based on questions that have been validated in previous Flemish and Dutch end-of-life studies, and avoided emotionally charged terms. It was tested thoroughly and a forward-backward translation was made for French speaking physicians in Brussels. Anonymity of both patients and physicians was guaranteed through a rigorous procedure, involving a lawyer as intermediary between responding physicians and researchers. To increase response we followed the total design method with follow-up mailings.

Discussion
Strictly anonymous and thorough surveys among physicians using a large and representative death certificate sample are appropriate in nationwide studies of incidence and characteristics of ELDs. Past studies in Belgium and other countries have shown the reliability and validity of this methodology.