Issues for causes of death data:
The main sources of non-sample error are:
completeness of an individual record at a given point in time ( e.g. incomplete causes of death information due to non-finalisation of coronial proceedings)
completeness of the dataset e.g. impact of registration lags, processing lags and duplicate records
extent of coverage of the population (whilst all deaths are legally required to be registered some cases may not be registered for an extended time, if at all)
lack of consistency in the application of questions or forms used by data providers. For example, sometimes old forms are used before being replaced with new forms and so there could be a period of overlap when a mixture of questions is used, or different questions are asked on death registration forms on the same subject. For occupation, the questions include main occupation during working life, usual occupation, and current occupation
particular data items which would be useful for statistical purposes may not be collected by jurisdictions where that item is not essential for administration purposes
question and ‘interviewer’ biases given that information for death registrations are supplied about the person by someone else. For example, Indigenous origin as reported by a third party can be different from self reported responses on a form. Forms are often not subject to the same best practice design principles as statistical questionnaires, and respondent and/or interviewer understanding is rarely tested
level of specificity and completeness in coronial reports or doctor's findings on the Medical Certificate of Cause of Death will impact on the accuracy of coding
errors can occur in coding of the causes of a death to ICD-10. Consistency between mortality coders is a contentious issue with literature suggesting only a 50% concordance between coders at the very detailed (four digit) level (McKenzie et. al., 2001).