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Keep & Merge Data

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An NHANES II dataset for analysis will typically include data from at least two data files. You will need to keep and merge data to include variables from different data files.


Task 1: Keep NHANES II Data

NHANES II data files were released by their collection method or component. Many of these are very large data files with many variables.  Most analysts will only need a few selected variables.  You will likely wish to keep only those variables when you create your analytic dataset. This process uses a SAS option statement called keep.


Task 2: Merge NHANES II Data

The NHANES II data files are organized by collection method or component, such as Physician's Examination or Hematology and Biochemistry. Joining the components of the data files uses a SAS statement called merge.

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