SEER*Stat results will be displayed or stratified by the format groups defined in the variables listed in the row, column, and page dimensions of the Table Tab. Therefore, use two mechanisms in SEER*Stat to define how your results are stratified:
- Using the dictionary, define format groupings for the variables of interest. For example, you may want to show frequencies for cases diagnosed in two 5-year periods (2000-2004 vs 1995-1999). In the dictionary, you would need to edit the "Year of Diagnosis" variable and create two groupings with the appropriate labels and values.
- Include the stratification variables in a dimension of the Table Tab. In our example, you would want to put your user-defined year of diagnosis variable in the row, column, or page dimension.
Example: Stratify Frequencies by Sex
Calculate the number of malignant primary tumors in the SEER 18 registries diagnosed in 1973-21.
- Start by opening a new Frequency session.
- Select the SEER 18 registry database on the Data Tab.
- Malignant tumors and known ages will be selected by default (due to the "Select only" check boxes at the top of the Selection Tab).
- To stratify results by sex, go to the Table Tab. Use the '+' next to the "Race, Sex, Year Dx, Registry, County" category in the list of "Available Variables" to expand the list of variables. Select the "Sex" variable, then use one of the available buttons to the right (Row, Column, Page) to add sex to the list of display variables. When you generate the results, the Sex variable is displayed by the three groupings defined for this variable in the SEER database: 'Male', 'Female', and 'Male and Female'.
Change Variable Groupings
A unique dictionary is associated with each SEER*Stat database containing one pre-defined, formatted variable for each data field. You can create your own formats for a field's values by creating new variables ("user-defined" variables). The variables distributed with a database are called "standard variables" and have pre-formatted groupings for common use. To view the definition of any variable:
- Open the dictionary by selecting Dictionary from the File menu, using the on the toolbar; or double-clicking on the variable in the Available Variables box or the Display Variables box on the Table Tab.
- Double-click the variable in the Dictionary window, or use the Create button to open the Edit Variable window and see the variable's definition.
- Groupings are essentially format statements that allow you to label individual or groups of values. When you click on a label in the Groupings box, the values associated with the label will be highlighted in the Values box. All values occurring in the database for the variable are listed in the Values box. The list of values cannot be changed.
To change the groupings for any variable in the database, you need to create a new variable, called a "user-defined" variable. Let's say you did not want to include the grouping for both sexes combined in the output of the example above. You would need to define a user-defined variable with just two groupings, "Male" and "Female", using the values available in the standard sex variable. This could be done by deleting the "Male and Female" grouping and saving the variable with a new name. Most of the tutorials include steps which provide detailed instructions for creating user-defined variables.
Setting Variables on the Table Tab
The dimensions (row, column, page) available on the Table Tab vary in the different sessions. In most sessions, you can choose the dimension to which the variable is assigned. A separate row, column, or page will be created for each of the variable's format groupings. The dimensions available in each type of session are:
- Frequency: Page, Row, Column
- Rate: Page, Row, Column
- Survival: Page, Row, Column (for Summary pages)
- Limited-Duration Prevalence: Page, Row, Column
- MP-SIR: Page, Row, Column
- Case Listing: Column