Spatial autocorrelation of cancer in western Europe

We applied the techniques of spatial autocorrelation (SA) analysis to 40 ca ncer mortality distributions in Western Europe. One of the aims of these me thods is to describe the scale over which spatial patterns of mortalities o ccur, which may provide suggestions concerning the agents bringing about th e patterns. We analyzed 355 registration areas, applying one- and two-dimen sional SA as well as local SA techniques. We find that cancer mortalities a re unusually strongly spatially structured, implying similar spatial struct uring of the responsible agents. The small number of spatial patterns (4 or 5) in the 40 cancer mortalities suggests there are fewer spatially pattern ed agents than the number of cancers studied. SA present in variables will bias the results of conventional statistical tests applied to them. After c orrecting for such bias, some pairwise correlations of cancer mortality dis tributions remain significant, suggesting inherent, epidemiologically meani ngful correlations. Local SA is a useful technique for exploring epidemiolo gical maps. It found homogeneous high overall cancer mortalities in Denmark and homogeneous low mortalities in southern Italy, as well as a very heter ogeneous pattern for ovarian cancer in Ireland.