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Limited-Duration Prevalence Session


Prevalence is a statistic of primary interest in public health because it identifies the level of burden of disease or health-related events on the population and health care system. Prevalence represents new and pre-existing cases alive on a certain date, in contrast to incidence, which reflects new cases of a disease diagnosed during a given period of time. Prevalence is a function of both the incidence of the disease and survival.

Limited-Duration Prevalence represents the number of people alive on a certain day who had a diagnosis of the disease within the past n years. SEER*Stat's prevalence calculations use the counting method to estimate prevalence from incidence and follow-up data. The counting method estimates prevalence by counting the number of persons who are known to be alive at a specific calendar time and adjusting for those lost to follow-up. For information on other methods for calculating prevalence, or estimating complete from limited-duration prevalence, please visit:

Note: See Statistics Calculated by SEER*Stat for an overview of the statistics that can be calculated in other types of sessions.

It is recommended that you work through a Limited-Duration Prevalence session in the following order.

  1. Create or open a Limited-Duration Prevalence session
  2. Data tab
  3. Selection tab
  4. Statistic tab
  5. Table tab
  6. Survival Cohorts tab
  7. Output tab
  8. Execute a Session
  9. View the output in a results matrix