Task 1: How to Decide Which NHANES Variables to Include

To identify the variables for your analysis you will need to check the survey documentation for the:

Info iconIMPORTANT NOTE

or the purpose of completing this module, assume you are preparing to do an analysis of cardiovascular disease using NHANES data. You will need to locate variables about age, gender, blood pressure, and cholesterol. Please read the Key Concepts About Deciding Which NHANES Variables to Include page before attempting these activities.

 

Step 1: Questionnaire

Beginning at the NHANES homepage, click the Questionnaires, Data Sets, and Related Documentation link in the navigation menu, then the NHANES 2001-2002 link, then the Survey Questionnaires, Examination and Laboratory Components link in the Contents in Detail section.

On the Survey Questionnaires, Examination Components and Laboratory Components 2001-2002 page, click the Blood Pressure link under the heading Sample Person Questionnaire.

The Adobe Acrobat PDF file of the survey documentation for the blood pressure portion of the questionnaire opens. Review the questions and determine which ones might be applicable to your analysis.

 

Step 2: Examination

From the PDF file of the Questionnaire survey documentation, click the browser's Back button to return to the Survey Questionnaires, Examination Components and Laboratory Components 2001-2002 page. Scroll down and click the Examination Components link to open the Adobe Acrobat PDF file of the survey documentation for the Examination component.

Use the Acrobat search feature (binoculars) to search for "blood pressure."

Reviewing the results, notice that the "hits" are related to the cardiovascular fitness, lower extremity disease, and physician's exam portions of the documentation. Read the related text and note that the results in the cardiovascular fitness and lower extremity disease portions would not be suited for your analysis, although they do mention blood pressure. The variables for your analysis are in the Physician's Exam portion where standardized blood pressure measurements are taken.

You must read the survey documentation to understand how variables were collected and their purpose in the survey. For more information, please see Key Concepts About Deciding Which NHANES Variables to Include page.