This section describes how to use SAS to identify food group sources of nutrients along with standard errors. To illustrate this, food sources of calcium are identified for the whole population, ages 2 and older, for 2001-2004. In this example, a simplistic food grouping scheme based on the first digit of the USDA food codes, was used for illustrative purposes.
Create a folder to save the dataset, list the contents of each dataset, and create a dataset comprised of 4 years of data. (Program not shown. See the full program in Additional Resources for more information.)
Sort and then merge the demographic and individual food intake datasets. Create new variables, as needed. Note that the food groups are simply characterized by first digit of individual food code: milk and milk products; meat, poultry, fish and mixtures; eggs; legumes, nuts and seeds; grain products; fruits; vegetables; fats, oils and salad dressings; and sugar, sweeteners and beverages. (Program not shown. See the full program in Additional Resources for more information.)