Introduction to the NLSY97 Created Variable Appendices

Introduction to the NLSY97 Created Variable Appendices

The main file NLSY97 data set contains a number of created variables. These created variables will be included on each public release of the NLSY97. With very few exceptions, these variables are either commonly used items that are derived from a number of different NLSY97 survey questions or longitudinal items that require updating in each round. If they were not provided, creating either the longitudinal or the cross-sectional variables might present difficulties for some NLSY97 users. In general, the created variables present information in five topical areas: Education, Employment, Family Background, Geographic Information, and Income and Assets.

Here is a list of the appendices included in the NLSY97 Codebook Supplement:

The first five appendices present SAS statistical programs that were used to create the NLSY97 variables.

Appendices 6 and 7 provide detailed information about the creation of the event history variables, a special set of variables included with the main data set. Appendix 6 describes the various status arrays available and discusses the creation and editing process. Appendix 7 explains the continuous month and continuous week systems used in the creation of event history variables and provides a crosswalk of continuous month/week and actual dates so that researchers can associate event history variables with other information about the respondents.

Appendix 8 describes the construction of "rosters" during the administration of the interview. Combined with the created variables, these organized lists are often the best source of information about a respondent's household, jobs, family, and schooling.

Appendix 9 provides information about the creation of various measures relating to adolescent family life and outcomes. These special variables were created by Child Trends, Inc. and are available for rounds 1-4.

Appendices 10, 11, and 12 describe the variables created from three special data collections. Appendix 10 details the administration of the computer-adaptive version of the Armed Services Vocational Aptitude Battery (ASVAB), which provides additional information about the abilities and aptitudes of NLSY97 respondents, including a created AFQT score. Appendices 11 and 12 discuss two transcript surveys, one for high schools and one for post-secondary institutions. These data collections required specialized coding and variable creation procedures to convey details about course of study and performance of respondents during their educational experiences.

Appendix 13 provides information on a NLSY79/NLSY97 cross-cohort beta release available on Investigator. The dataset harmonizes NLS data across two cohorts, giving users opportunities to perform cross-cohort comparisons. See Cross Cohort Harmonization Overview document for more information. To access the data, go to and select "NLS Cross Cohort Beta."

A supplemental COVID-19 survey, fielded in the spring of 2021 to document the effects of the pandemic on respondents’ jobs and health, is the topic of Appendix 14. Respondents received invitations to complete a short (about 12 minute) web questionnaire about their experiences during the pandemic.

Several created variables don’t fit within specific appendix topics; these are detailed below.

Interview date and age of respondent

Variables Created


The date of the interview is presented, along with the respondent’s age. CV_AGE_MONTHS_INT_DATE and CV_INTERVIEW_CMONTH then convert the date and age into the continuous month format used in some event histories. (See Appendix 7 for a further explanation of the continuous month scheme.)

Link to Interview Date program file

Round last interviewed

Variable Created

CVC_RND -- Indicates the round in which the respondent was last interviewed; this is the round which is represented in CVC variables for that respondent (except when noted on the codebook page of a CVC variable).

Link to Round program file