Interview Methods

Interview Methods

Fielding Periods

With the exception of round 1, the NLSY97 fielding periods began in the fall of the survey year and continued through the spring of the following year. Surveys were conducted annually through round 15, with biennial interviews beginning in round 16.

Created Variables

Use these created variables for respondent's interview date (month and year only):

For all rounds 2 and up, use (1) CV_INTERVIEW_DATE~M and (2) CV_INTERVIEW_DATE~Y. (For round 1, the variables are (1) CV_INTERVIEW_DATE_M and (2) CV_INTERVIEW_DATE_Y).

To determine the date of the previous interview, researchers should first identify the round when the respondent was last interview (see SYMBOL!ROUND), then pick up the corresponding date of interview for that round.

CV_INTERVIEW_CMONTH, the respondent's interview month in continuous month scheme, also is available. (A continuous month scheme labels January 1980 as month 1, February 1980 as month 2, and so on)

Locating respondents is a coordinated effort of NORC's central office, locating shop, and local-level field staff. Prior to fielding, NORC's central office sends a short, informative "locator letter" to each respondent reminding him or her of the upcoming interview and confirming the respondent's current address and phone number. During the field period, field interviewers use contact information to track down hard-to-find respondents, while central office staff assist with database searches and other centralized locating methods.

Round 1 fielding period

Most round 1 NLSY97 interviews were conducted between January and early October 1997. Due to concerns about the number of eligible youths found during the initial field period, investigators decided to conduct a refielding between March and May 1998. During this second part of the initial survey round, 395 additional respondents were interviewed. These respondents (identified in the dataset as CV_REFIELD_YOUTH) were administered the same instrument as those initially interviewed in 1997.

Researchers analyzing topics where time periods are critical should carefully examine the reference period of the questions and the actual interview date for individual respondents. In particular, the round 1 fielding period has implications for questions on education; see Educational Status & Attainment for more information.

Researchers should also pay close attention to the elapsed time between interviews for each respondent. While the time between the first and second interviews was about 18 months for most respondents, it may be less for those first interviewed during the refielding period.

Rounds 2 and up fielding periods

Most respondents were surveyed approximately 18 months after their first interview, although the elapsed time between interviews was substantially less for some respondents. Subsequent fielding periods also began in the fall. Respondents were surveyed annually through round 15, then biennially starting in round 16.

Table 6 provides fielding periods along with sample size and retention rates for each round.

Table 6. NLSY97 Sample Sizes, Retention Rates, and Fielding Periods

Round Fielding period Cross-sectional sample Supplemental sample Total sample
Total Retention rate Total Retention rate Total Retention rate
1 February-October 1997 and March-May 1998 6748 -- 2236 -- 8984 --
2 October 1998-April 1999 6279 93.0% 2107 94.2% 8386 93.3%
3 October 1999-April 2000 6172 91.5 2036 91.1 8208 91.4
4 November 2000-May 2001 6054 89.7 2026 90.6 8080 89.9
5 November 2001-May 2002 5918 87.7 1964 87.8 7882 87.7
6 November 2002-July 2003 5898 87.4 1998 89.4 7896 87.9
7 October 2003-July 2004 5782 85.7 1972 88.2 7754 86.3
8 October 2004-July 2005 5600 83.0 1902 85.1 7502 83.5
9 October 2005-July 2006 5437 80.6 1901 85.0 7338 81.7
10 October 2006-July 2007 5624 83.3 1935 86.5 7559 84.1
11 October 2007-July 2008 5521 81.8 1897 84.8 7418 82.6
12 October 2008-July 2009 5560 82.4 1930 86.3 7490 83.4
13 September 2009-April 2010 5616 83.2 1943 86.8 7559 84.1
14 October 2010-June 2011 5544 82.1 1935 86.6 7479 83.2
15 September 2011-June 2012 5501 81.5 1922 86.0 7423 82.6
16 November 2013-July 2014 5285 78.3 1856 83.0 7141 79.5
17 October 2015-August 2016 5271 78.1 1832 81.9 7103 79.0
18 October 2017-October 2018 5018 74.3 1716 76.7 6734 75.0
19 September 2019-July 2020 5168 76.6 1779 79.6 6947 77.3
20 September 2021-October 2022 4967 73.6 1746 78.0 6713 74.7
 
Note: Retention rate is defined as the percentage of base year respondents remaining eligible who were interviewed in a given survey year; deceased respondents are included in the calculations.