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.

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