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Append & Merge Data

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An NHANES dataset for analysis will typically include data from 2 or more years and variables from more than one component. You will append to combine the years of data and merge to include variables from different components.


Task 1: Append NHANES Data

NHANES data files are released for public use in 2-year groupings. You may wish to combine multiple years, add additional observations, or combine different years of data files on the same variables. The process of combining years is called appending.


Task 2: Merge NHANES Data

Data files are organized by their collection method, which can fall under one of four components: Demographic, Examination, Laboratory, and Questionnaire. To allow for timelier releases, different components of the data files are usually released at different times as they are completed. Joining the components of the data files is called merging.



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