• cause of death
• death certification
• diagnosis
• mortality

Various methods have been used to evaluate the quality of cause of death statistics.^1,2 Traditionally, necropsy findings were deemed as the gold standard to evaluate the accuracy of cause of death certification. However, because of the biased selection of necropsy cases and the decreasing necropsy rate, fewer and fewer evaluation studies have used necropsy findings as the standard.³ Another commonly used standard to evaluate the quality of death certification is the consensus of a panel of physicians reviewing all available information related to the deceased.⁴ Most of the studies using this method were the byproducts of large cohort studies or randomised clinical trials. These studies wanted to assure that the end point was not biased. The shortcomings of using physician review as the standard were time consuming, costly, not applicable in a large scale and routinely.^5,6

As more and more disease specific registries and hospital medical records were computerised, more and more investigators began to use these datasets as the standard to evaluate the quality of cause of death statistics. The merits of this method were time saving, less costly, applicable in large scale and routinely. Several population based studies used computer linkage of cause of death file and hospital discharge file to compare the underlying cause of death (UC) and discharge diagnosis.^7–10 Almost “every” deceased were medically attended in developed countries, these studies could thus evaluate the quality of “every” death certification. Johansson and Westerling attempted to develop a systematic and routine monitoring mechanism at the national level that can detect the poor death certification “before” the publication of mortality data.¹⁰ Unlike the previous post hoc studies, through this monitoring system, once the poor quality of death certification was identified, they could immediately query the certifier to modify the death …