WEAT: Web Enabled Analysis Tool

Cross Tabulation Information

EXAMPLE:
Cross tabulations allow you to generate tables with frequencies across two or more categorical variables. For example, imagine that you are interested in learning whether men exercise more than women. The BRFSS dataset includes two 2-level variables to help answer this question. Gender is answered "male" or "female," and exercise in past 30 days is answered "yes" or "no."

To generate a table to help answer this question, you would follow these steps:

1. From the Cross tabulations page, scroll down the variables listed under "Step 1 Select Row" and select "Exercise: Exercise past 30 days."
2. Under "Step 2 Select Column," select the variable "Demographic: Gender."
3. Under "Step 3 Control 1 (optional)" leave the default value "None."
4. Under "Step 4 Control 2 (optional)" leave the default value "None."
5. Check off those statistics that are of interest, or leave the check marks that appear already. At a minimum, you will probably want to read column and row percentages, although other statistics may be of interest.
6. Click on "Run Table."
7. Review the resulting table on your screen.

Note: You could select sex as the row variable and exercise as the column variable. However, some analysts prefer reading the independent variable in columns and dependent variable in rows.

Sometimes you may want to introduce a third variable (control variable) to your analysis. For example, imagine that you want to learn whether gender affects exercise, and whether the influence of gender increases (or decreases) for older adults. To answer this, you would follow similar steps, but add a single control. In Step 3 above you would go to "Step 3 Control 1 (optional)" and select "Demographic: Reported age (18-64, 65+)." Once you click on "Run Table, you will create two tables containing data for 18-64 years old and 65 and older.

Finally, you may be interested in introducing a fourth variable to refine your analysis even further. Perhaps your analysis have demonstrated that gender affects exercise, and the influence of gender increases for older adults, but now you wonder whether that age differential is moderated by diabetes. To answer this, you would follow the same steps, adding two controls. For "Step 3 Control 1 (optional)" you would select "Demographic: Reported age in two age groups." For "Step 4 Control 2 (optional)" you would select "Diabetes: Doctor ever said you have diabetes." This will produce six tables reporting exercise frequencies for young and old, with and without diabetes.

Every time you want to return to the Cross tabulation page to add or change variables, click on the button "Modify the Crosstab Model," or click on the back arrow on your browser. Your original selected variables will be available for you to modify as needed. If you want to download results to a spreadsheet, click on the button "Download to Excel Spreadsheet."

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