0: Death certificate only: Information provided is from a death certificate.
1: Clinical: Diagnosis made before death.
2: Clinical investigation: All diagnostic techniques, including X-ray, endoscopy, imaging, ultrasound, exploratory surgery (such as laparotomy), and autopsy, without a tissue diagnosis.
4: Specific tumour markers: Including biochemical and/or immunologic markers that are specific for a tumour site.
5: Cytology: Examination of cells from a primary or secondary site, including fluids aspirated by endoscopy or needle; also includes the microscopic examination of peripheral blood and bone marrow aspirates.
6: Histology of a metastasis: Histologic examination of tissue from a metastasis, including autopsy specimens.
7: Histology of a primary tumour: Histologic examination of tissue from primary tumour, however obtained, including all cutting techniques and bone marrow biopsies; also includes autopsy specimens of primary tumour.
9: Unknown: No information on how the diagnosis has been made.