Reduction of Death Certificate Only (DCO) Registrations by Active Follow Back.

Death certificates are an important source of information for cancer registries that help to improve completeness of case finding. In many countries where routine mortality data are considered of poor quality, this source is often regarded as being of little value. We evaluated the contribution of death certificates to the total number of registrations in the years 1993-1997, in the Manila Cancer Registry (MCR). We compared the "standard" practice of retrieving clinical information if the death certificate was completed in a hospital, with active search of additional information from the deceased's relatives when the death was certified at home.The standard procedure allowed us to reduce the proportion of cases registered from a death certificate by 5%. The improvement varied significantly among the most common sites with a reduction of 10% for lymphomas to less than 1% for cancers of the cervix.The proportion of liver cancers registered from a death certificate only (DCO), originally 47%, was reduced to 29% by contacting relatives of the deceased patients. In countries with limited investment in information systems, death certificates, even when recognised as being of poor quality, are an important source of information for cancer registries.