10.0 The FERTILE Variables

The FERTILE Area of Interest is another area with which you should be familiar. Many of the variables in this grouping were created and made consistent for you. Among them are 'age at first marriage', 'age at first birth', 'number of children in the household', 'dates of birth of children', 'sex of children', 'residence of children', etc.

Open this area of interest in the Variables window and sort it on Description. You will find the following variables among others that may be of interest.

• R0898845   AGE BEGAN 1ST MARRIAGE 82 INT  R08988.45  [*Created]
• R0898840   AGE OF R AT 1ST BIRTH 82 INT  R08988.40  [*Created]
• R0218001   NUMBER OF BIO/STEP/ADPT CHILDREN IN HOUSEHOLD 79 INT  R02180.01  [*Created]
• R5083600   DATE OF BIRTH OF 1ST CHILD  R50836.00  [C1DOB94]
• R0898805   SEX OF 1ST CHILD 82 INT  R08988.05  [*Created]
• R0898806   USUAL RESIDENCE 1ST CHILD 82 INT  R08988.06  [*Created]

In the codebook window, look at these variables and others that may be of interest to you. Use the 8.3 Process of Finding Variable Details to discover more about them.

The documentation, NLSY79 User's Guide, provides you with supplemental information on the 'fertility' topic. Look in the Table of Contents, Chapter 4.14 to find out more about 'fertility'. A brief portion of this Chapter is reproduced below.

NLSY79 "Every NLSY79 survey has included a section on fertility. In each survey year, both men and women are asked if they have had children. NLSY79 surveys are designed so that it is possible to construct a detailed history of each respondent's fertility. The first three NLSY79 surveys (1979, 1980, 1981) have very short fertility sections. In 1979, respondents were asked if they had ever had any children. For those individuals who answered "yes," the number of children as well as their birth dates were recorded. In addition, youths were asked about the total number of children they desired and expected to have. The 1980 and 1981 surveys updated information for respondents who had any children since the last survey."

NLSY79 User's Guide Chapter 4.14 Fertility

NLSY79 Fertility History ...A complete description of the contents of the FERTILE area of interest is provided in Appendix 5 of the NLSY79 Codebook Supplement. This appendix also describes how the data were checked, lists research reports that investigate the quality of the data, and explains special coding and edit flags.

NLSY79 User's Guide Chapter 4.14 Fertility

When you locate Appendix 5 of the NLSY79 Codebook Supplement, it has this (and more) to say about the "Supplemental Fertility File Variables (1998)":

FILE CONTENTS The supplemental fertility data file, FERTILE, contains a variety of constructed and edited variables based upon the fertility and marriage histories of respondents from the 1979-1996 National Longitudinal Surveys of Youth (NLSY). These variables enable users to more easily access the wealth of demographic information provided by the surveys and improve the internal consistency of such data across survey years. The file contains dates of birth, sex and usual living arrangements for all respondents' children based on a review of the longitudinal data record. Beginning in 1994, the two-digit IDs of the biological children of the female respondents were added to FERTILE, as were separate edit flags for male and female respondents. Also included are created variables that summarize dates of marriage(s), number of live births and other pregnancy outcomes, spacing between births, spacing between first birth and first marriage and age of respondent at the time of the first marriage and key fertility events. The variables included in this file are based upon the youth fertility data as revised in a data cleanup program undertaken in 1982-1983 with additional editing provided at selected subsequent survey points.

NLSY79 User's Guide Appendix 5 of the NLSY79 Codebook Supplement

In the next section we will briefly run through the process of creating an extract. Much more about running an extract and the sophisticated operations available in the software can be found in the software manual, CHRR Database Investigator User's Manual. This manual is on your CD, link to it under the subdirectory "Documents" in the Contents window.