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Surveillance Research Program

Example 1

An example of 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, 2015 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 that 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. Start the ComPrev application. 

  3. Select File, New Session from the menu. 

  4. For Type of Session, select Complete Prevalence. Then press the Next button at the bottom of the window. 

  5. Since you are using the built in data file for ComPrev, just press the Next button on the Inc\Surv Parameters tab. 

  6. On the LDP tab, you will need to select your LDP data dictionary. Under step 1, where it says DIC File, press the Browse button. In the Open File dialog that is displayed, navigate to where you downloaded the file "US.jan1.2015.female.breast.40yearldp.by.age.dic", and select the file, and press the Open button. Steps to create the U.S. limited-duration prevalence using SEER*Stat and Projprev are available with the Projprev software.

  7. You will now see a messagebox that is warning you that the data file (.TXT) could not be found at the specified location, but a file with the same name was found in the same directory, and that will be the file used. This is just fine, so press OK. 

  8. Next press the Mapping... button under Step 2. The Data Mapping window will be displayed. This window lets you tell ComPrev how to map your data file to its internal data. 

    • At the top of the window, you will see 3 combo boxes. These three combo boxes allow you to select the variables within the LDP file and how they match up to the variables within Comprev's default data source. Comprev has already tried to match them up on its own. The values shown in these combo boxes indicate that Comprev could not find an equivalent variable in the LDP file for Site or Sex, but it did find one for Race. So far this is correct. The LDP data file you used only has a single variable within it called Race. So you need to tell Comprev what to use for the other two variables.

    • Select the combo box in the first row for "Site". Since there is no variable in the LDP file to match up, we need to tell Comprev to just use one single constant value for the "Site" variable. The very top item in the list displayed from the combo box is "[No LDP field. Select Comprev value below:]". You want to scroll down the list until you see an entry under this called "Breast" and select it. You are telling Comprev to just use the single value "Breast" for the "Site" variable.

    • The second combo box for the field "Race" has already been selected for the variable "Race recode" from the LDP file. If you select this row in the list (not the combo box itself, click on the row in the left column), you will see a list of values displayed in the lower table under "Output Values for Field". This shows that Comprev has 4 values for the variable "Race", and that it has already selected that the LDP file's value of "All Races" should match the Comprev value of "All Races". This is correct since the LDP file only contains a single race called "All Races".

    • Next select the combo box in the third row of the top table in this window for the Comprev Field "Sex". This is another variable that Comprev's default data source contains, but the LDP file does not. For this we want to select the value "Female", since the data in the LDP file is for Breast / All Races / Female. When you are done making this selection, you have completed your mapping of this file and can press the OK button. 

       

  9. Back on the Session Setup window - LDP tab, press the Next button. On the Selection tab, you will see that the values for Breast, All Races, and Female are already selected for you. These values were determined from your LDP data file. Press the Next button. 

  10. On the Settings tab, you can see that most of the information is already filled in for you from the LDP data file. The Prevalence Date is 1/1/2015, the Initial Data of Diagnosis is 1975, and the number of Age Groups is 19. Press the Finish button at the bottom of the window. 

  11. A Progress Window will be briefly displayed while ComPrev is calculating the complete prevalence statistics. When they are done, the Main window will be displayed. 

  12. On the left side of the Main Window, the list of cohorts to view are displayed. Since we only had data for one cohort, we just have the Breast \ All Races \ Female cohort available. 

  13. On the right side of the Main Window, 5 tabs are displayed. 

    • Incidence: You can view the incidence parameters used by ComPrev as a table or graph. 

    • Survival: You can view the survival parameters used by ComPrev as a table or graph. 

    • 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.

    • Prevalence Estimates: You can view the results as a table or graph. The table includes the completeness index (percents), the limited-duration and complete prevalence (percents and counts), and the U.S. population by age. SE's (Standard Errors) are included if requested. The first graph, Limited Duration Prevalence vs. Complete Prevalence, allows you to view the Counts and Percents of the Limited Duration overlapping that of the Complete Prevalence. The second graph, Complete Prevalence Count, allows you to view the counts for each age group. 

    • Settings: Displays all of the information you specified to create this session. 

  14. 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.