Completeness and Accuracy of Death Registry Data in Golestan, Iran

We aimed to evaluate completeness and accuracy of the Golestan Death Registry (GDR) to identify cancer-related causes of death (CCoD).

The GDR data (2004-2015) were compared with cancer data collected from clinical/pathological sources (the considered gold standard) by the Golestan Population-Based Cancer Registry (GPCR). Using a linkage method, matched cases, including subjects with CCoD and those with ill-defined cause of death (ICoD) (garbage codes), were identified and entered into the final analysis as study subjects. The completeness (percentage of study subjects with CCoD) and accuracy (number of subjects with correct CoD from the total number of study subjects) of the GDR were calculated.

In total, 3,766 matched cases were enrolled. Overall, the completeness and accuracy of the GDR for identifying CCoD were 92.7% and 53.2%, respectively. There were variations by cancer site and age group, with completeness and accuracy highest for brain cancer (96.3%) and leukaemia (79.8%) while the lowest accuracy was observed for colorectal cancer (29.9%). The completeness and accuracy of GDR was higher in patients aged under 60 years (95.7% and 53.6%, respectively). We also found higher completeness (93.7%) and accuracy (55.8%) in residents of rural areas.

Linkage of death registry data with cancer registry data can be a significant resource for evaluating quality of the death registry data. Our findings suggested that completeness of the GDR for identifying CCoD is reasonable, but accuracy is relatively low. Access to clinical and pathological data from other sources and enhanced training of death certifiers can improve the present situation.