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Example 1: U.S. Female Breast Cancer for All Races by Age at Prevalence

Objective

Calculate U.S. complete prevalence for malignant female breast cancer on January 1, 2002 for all races combined using ComPrev.

Key Point

The population of the SEER 9 registries does not have the same age-specific racial breakdown as the U.S. Completeness indexes are available for all races combined, white, black, and Hispanic. Since, we do not have completeness indexes available for other detailed races we must first project SEER limited-duration prevalence to the US by race and then sum across the races to get all races combined. Then, we will use the all races combined completeness index to estimate all races complete prevalence in the US.

Steps

  1. Before we get started, please download and save the following .dic and .txt files to your computer. These files will be needed in a later step.
  2. Using the drop-down list box, switch the mode to Single Group | Compute Completeness from Imported Limited Duration Prevalence | Default Parameters Only. This will to allow us to import limited-duration prevalence statistics and calculate complete prevalence.
  3. Select Site in the Variable Selections list box and then Breast in the Values list box. Repeat this process to select Race = All races and Sex = Female.
  4. Use the import limited-duration prevalence tool bar button to load the prevalence dictionary file (us.ldprev.female.breast.byage.dic) that you downloaded at the start. Steps to create the U.S. limited-duration prevalence using SEER*Stat and Projprev are available with the Projprev software.
  5. Once the limited-duration prevalence statistics are loaded, ComPrev will calculate the complete prevalence statistics. When the calculations are complete, 4 new tabs will appear and you will be switched to the Completeness Index tab. Note, that on the Cohort Selection tab we did not specify the prevalence year, start year, duration or age variable. These settings were set automatically when the dictionary is loaded. The 4 new tabs are:
    • Incidence: You can view the incidence parameters used by ComPrev.
    • Survival: You can view the survival parameters used by ComPrev as a table or as graphs.
    • Completeness Index: Contains a table with completeness index and standard error (if requested) by age at prevalence as well as a graph of the completeness index.
    • Revalence Estimates: This includes the completeness index, percents, counts, and SEs (if requested), and the U.S. population by age. Both limited-duration and complete prevalence percents, counts, and SEs are included.
  6. Even though we did not calculate the limited-duration prevalence statistics with an all ages category, one is added to the results. Because ProjPrev included the populations in the data file, ComPrev is able to calculate the limited-duration and complete prevalence percents for the all ages category. If populations were not included, these statistics could not be calculated.

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