LimitedDuration Prevalence
LimitedDuration Prevalence represents the proportion of people alive on a certain day who had a diagnosis of the
disease within the past x years (e.g. x = 5, 10 or 20 years). Registries of shorter duration, less than 40 or 50 years of
data collection, can only estimate
limitedduration prevalence.
Limitedduration
prevalence can be further classified into periods from year of diagnosis. Thus, the 20years prevalence can be further classified
into the prevalence of those diagnosed in the last 0 to < 5 years, 5 to < 10 years, 10 to < 15 years, and 15 to < 20 years.
NCI's SEER Program has information
on cancer cases since 1973; however, prevalence calculations usually
begin in 1975 due to a different number of registries participating
in years 19731974. Thus a maximum of 30year prevalence can be
estimated from SEER cases diagnosed from 1975 through 2004.
Limitedduration prevalence statistics can be calculated using the SEER*Stat
software.
