The Use of Self-Generated Identification Codes in Longitudinal Research

Abstract

Longitudinal research designs involve data collection at multiple time points to measure change over time. Therefore, identification of the same respondents is essential at each time point so that data from the same respondents can be matched for comparison over time. Subject-generated identification codes permit an anonymous means to track respondents over multiple data collection points. This article describes the evolution of subject-generated identification codes, techniques to improve respondent match rates, and the authors' experience using this mechanism in a longitudinal study of staff registered nurses working in hospitals. Challenges, recommendations, and implications for using subject-generated identification codes are discussed.

Reasons for Trying E-cigarettes and Risk of Continued Use

“…3,7 Data were obtained from schoolwide surveys that were repeated in 2 middle schools and 3 high schools in fall 2013 and spring 2014. Surveys were matched across time points by using a self-generated identification code (SGIC) 18,19 composed of 6 unique indicators: first letter of middle name, second letter of last name, day value from date of birth, school, homeroom, and sex. This method has been used in other longitudinal studies in which preserving anonymity is important, such as collecting data on youth substance use.…”

“…This match rate is comparable to other anonymous longitudinal surveys. 19,22 Sample characteristics at wave 1 were compared between the matched and unmatched sample. Match rates were slightly higher among female students (77.7%) compared with male students (71.0%) (χ 2 test [n = 2822], 16.71; P < .001).…”

Proximal Correlates of Suicidal Ideation and Behaviors: A Test of the Interpersonal‐Psychological Theory of Suicide

“…Given that the data were anonymous, participants' baseline and daily survey data were linked using subject-generated identification codes. Participants created a seven-letter unique identifier that was used to link their baseline and daily surveys (Yurek, Vasey, & Havens, 2008).…”

Secondary Traumatic Stress Among Internet Crimes Against Children Task Force Personnel

“…There have been calls for longitudinal research in the area of STS (Bride, 2011;Moulden & Firestone, 2007;Salston & Figley, 2003), and we agree it is important to examine this problem over time. In light of this need, we included subject-generated identification codes (see Kearney, Hopkins, Mauss, & Weisheit, 1984;Yurek, Vasey, & Sullivan Havens, 2008) in our survey that allow respondents to remain unidentifiable yet will allow us to conduct follow-up studies at a future date. The sample was very specific to a certain profession that investigates online child sexual exploitation.…”