Survey Instruments

Survey Instruments

The primary variables found within the main data set are derived directly from survey instruments, such as questionnaires, household interview forms, and so forth. This section describes each of the NLSY79 instruments in the order that they appear within Table 1. It also explains the conventions used in the NLSY79 documentation system to identify questionnaire items from some of the primary survey instruments. An additional document, the interviewer reference manual, provides background information on specific survey instruments.

Important Information

Questionnaire Item or Question Number. This generic term refers the user to the printed source of data for a given variable. A questionnaire item may be a question, a check item, or an interviewer's reference item that appears within one of the survey instruments. Each questionnaire item has been assigned a number or a combination of numbers and letters within the NLSY79 documentation system to assist the user in linking each variable to its location in a survey instrument. NLSY79 questionnaire item assignment is complex and varies across survey years and instruments. For some years, NLSY79 questionnaire item identification is dependent upon various combinations of the deck and column numbers used in data entry that are printed to the right of the answer categories on the survey instrument. In other years, designation is made by section and question numbers. Specific information on the conventions used appears below, after each relevant instrument, under the subheadings "Question Numbering."

Table 1. Types of NLSY79 Survey Instruments & User Aids

1978 Household Screener; Household Interview Forms
Interviewing Aids
  Face Sheet
  Information Sheet
  Children's Record Forms (CRF)
Questionnaire Supplements
  1979 High School Survey
  1980-83 Transcript Surveys
  1980 Illegal Activities Form J
  Employer Supplements (ES)
  1983 Fertility Supplement
  Confidential Abortion Forms
  1988, 1992, 1994, and 1998 Drug Use Supplement
  1988 Childhood Residence Calendar
Interviewer Reference Manuals (Q by Qs) and CAPI Help Information

A unique set of survey instruments has been used during each survey year to collect information from respondents. The term "survey instrument" is used to refer to:

  1. the questionnaires that serve as the primary source of information on a given respondent
  2. questionnaire supplements fielded during select survey years that contain additional sets of questions
  3. documents such as the household interview forms or household record cards that collect information on members of each respondent's household

Users should be aware that, while the source of the majority of variables in the main NLSY79 data files is the questionnaire or one of the other survey instruments, certain NLSY79 variables are created either from other NLSY79 variables or from information found in an external data source (see Types of Variables).

Household Information

Each NLSY79 interview includes the collection of information on the members of each respondent's household. For NLSY79 respondents, such household data are collected prior to the administration of the main questionnaire and for many years used separate survey instruments called the Household Interview Forms. Both the instruments used for the yearly household data collection and the household screening instruments that were used to draw the samples of respondents are described below.

NLSY79 1978 Household Screener and Interviewer's Reference Manual. This document (fully titled NLSY-National Longitudinal Survey of Labor Force Behavior Interviewer's Manual-Household Screening, NORC 1978) contains detailed information on the 1978 screening of households conducted by NORC from which the civilian youth samples (the cross-sectional and supplemental samples) were drawn. It provides a copy of the short 25-question screener, question-by-question specifications for administering the form, and a sample completed screener. Most of the information collected on each respondent during the screening is presented within the data set. The screener is the source for important data such as the sex and race or ethnicity variables that were used to assign each respondent to a specific NLSY79 subsample, as well as the relationship codes (for example, brother, sister, husband, wife) that allow researchers to identify related NLSY79 respondents who shared a household at the time of the screening.

Question Numbering. Question numbers for the 1978 screener were arbitrarily assigned by NORC using an artificial questionnaire section number that followed the last section of the 1979 questionnaire ("Section 25" for all screener variables) even though the actual administration of the screener preceded that of the 1979 questionnaire.

Users should note that screener questions are identified within the documentation as 1979 variables even though these data were collected during 1978. Most variables from the screener use the phrase HOUSEHOLD SCREENER at the beginning of the variable title, appear physically within the codebook after the 1979 household record series, and have been placed within the "Misc. 1979" area of interest.

Household Interview Forms. Yearly household information for the NLSY79 is collected from either the respondent or the head of household prior to the administration of the main questionnaire. NLSY79 Household Interview Forms are used to:

  1. enumerate all persons currently living in the respondent's household
  2. record information about each person's age, highest grade completed, work experience in the past year, and relationship to the respondent
  3. collect, during the 1979-86 surveys, certain family income information

Information on household members is collected using the questions on the Household Interview Forms; however, much of the information is actually recorded on the "Household Enumeration" section of the Face Sheet discussed below.

During the 1979-86 interviews, different versions of the Household Interview Forms were administered depending upon the type of residence of the respondent. Version A was used if the respondent was living with his or her parents (or in-laws), in which case the interview was conducted with the respondent's parents (or in-laws) in order to gather information on household income sources. Version B was used if the respondent was living in group quarters, such as a dormitory or the military, or in temporary facilities, such as a hospital or prison, and was administered to the respondent. If the respondent had a permanent residence elsewhere, the household interview gathered information about that household. Version C was administered to the respondent if he or she was living in his or her own dwelling unit, military family housing, an orphanage, a religious institution, or other individual quarters or was the head of a family unit. Table 1 in the Household Composition section of depicts, by survey year, the universe and residential unit(s) specific to each form.

During the first eight survey rounds, many respondents were younger than 18 and living with their parents; thus, Version A was frequently used. Beginning with the 1987 survey, all respondents were 21 or older and living predominantly on their own; consequently, the household interview forms were consolidated into a single version. For 1979-86, these forms appear as separate documents. Beginning with the 1987 interview, household interview questions were incorporated within each year's questionnaire. Some variation in administration of these forms has occurred over survey years. Users should refer to each survey year's Interviewer's Reference Manual for more information.