2 Data

Maps are based on the municipality-specific cancer registry data from each of the five Nordic countries over the period 1971-2003, with the exception of Denmark, whom was able to submit data only up to and including 2001. Cancer registration is available in Denmark from 1943, in Finland and Norway from 1953, in Iceland from 1955, and in Sweden from 1958. Unlike the other countries, Finland has tabulated cancer incidence rates by municipality from the beginning of the registration period (see http://www.cancerregistry.fi/eng/statistics/9-64-152.html).

To produce animated maps, cancer incidence rates were calculated for each municipality for 6-year periods 1971-1976, 1974-1979, …, 1998-2003, adjusted for age using the World Standard Population. In Denmark, rates for 1998-2001 were used for the latest period.

For a given municipality, the observations were assigned to geographical central points ; other geographical data needed included geographical data with respect to the specific coordinates of national borders (using Alber’s equal area projection (Snyder, 1987)), major lakes,waterways as well as sparsely-populated areas.