Cancer Registration: Principles and Methods - IARC

Reporting of results
Dlgestlve organs
Respiratory sys.
Male genltal org
Urinary system
Blood, Lymphatic
Other speclffed
Sec. a d unspec.
~uccaQ pharynx
Year
Figure 8. Trends in age-standardized incidence rates of cancer of selected sites in males in
Denmark, 1943-85
Line-graph, arithmetic scale
Age-specific incidence rates are most commonly plotted by line-graphs. Such plots
can be done either on an arithmetic or a semilogarithmic scale (with ages on the
arithmetic and rates on the logarithmic axis). On the logarithmic scale the relative
increases or decreases in rates are of identical magnitude, irrespective of the absolute
values. Plotting of age-specific incidence rates will quickly reveal differences in age
curves for different sites, as in Figure 5, or for different time periods. Trends in agespecific
incidence rates are also best presented by line-graphs. This can easily be
combined with a graphical presentation of age-specific rates for birth cohorts as
illustrated in Figure 6. An alternative approach is the presentation of age-specific
incidence rates for individual birth cohorts, as shown Figure 7. The annual age-