Research Note: An Empirical Study of Adolescent Student Attrition

Abstract

Sample attrition, a major concern in any longitudinal study, is even more problematic when adolescents are the study population. The need to minimize the loss of participants in order to maintain the integrity of the cohort is vital in substance abuse prevention evaluations. The Adolescent Substance Abuse Prevention Study (ASAPS), a national school based prevention study being conducted in six sites across the country, followed students attending schools randomly assigned to either a treatment or control condition from the seventh through the eleventh grade. The percent of study dropouts after the ninth grade pretest warranted consideration of an attrition study to acquire data from those students who were no longer in a study school. A pilot study conducted with a sample of attrition cases in one site (51 of 495) was undertaken to assess the feasibility and costs of a full study. This paper describes the experiences gained from this pilot study in tracking study subjects. An exhaustive protocol was developed and contacts with parents were initiated through telephone calls and flyers sent by mail. Online public records and telephone directories were used to acquire additional contact information. Contact was established with 56.8% of the parents and resulted in completed surveys from 19.6% of the sample at a cost of $1,949.30 per survey.

Persistence Pays Off: Follow-Up Methods for Difficult-to-Track Longitudinal Samples

“…Not surprisingly, spending a lot of money (Stephens et al, 2007), time (Desmond et al, 1995), and effort (Cottler et al, 1996) are crucial to retaining diffi cult-to-follow populations. Researchers tend to use fi ve primary methods to complete follow-up interviews: (1) calling participants, (2) calling their friends and family members (i.e., collaterals), (3) mailing reminders, (4) searching public records for updated or missing contact information, and (5) providing monetary incentives.…”

“…This strategy provides an early opportunity to detect change of address (Meyers et al, 2003). Letters also remind participants to expect a follow-up call before any other tracking methods begin (Stephens et al, 2007). Another type of mailing reminds people who are unresponsive to calls about the study and asks them to contact the research team (Boys et al, 2003;Lapham et al, 2000).…”

“…Foresight during study design is essential to improving completion rates. The contact information that participants provide during their baseline interview includes the information necessary for longitudinal tracking (Cottler et al, 1996;Meyers et al, 2003); however, one study (Stephens et al, 2007) found a weak relationship between the amount of information collected at baseline and completion rates. The type of information, more than the amount, infl uences follow-up.…”

“…The type of information, more than the amount, infl uences follow-up. Given current privacy regulations, unless participants explicitly agree, using public or private records such as voter-registration records (Stephens et al, 2007), motor vehicle directories (Lapham et al, 2000), records of debit card use (Des Jarlais et al, 2005), or other information collected on a contact sheet to track participants might not gain IRB approval. Participants who provide this information imply consent, but consent forms must clearly give permission for researchers to use this information (Desmond et al, 1995;Stinchfi eld et al, 1994;Vaillant, 1975).…”

Reaching everyone: Promoting the inclusion of youth with disabilities in evaluating foster care outcomes

“…In general, transition-age youth in care are likely harder to retain in longitudinal outcome studies relative to peers that are not child welfare system-involved, as foster care factors play a role in finding and retaining these participants. For example, youth in foster care are often not locatable through their parents like other adolescent research participants (Ribisl et al, 1996; Stephens, Thibodeaux, Sloboda, & Tonkin, 2007), they are more likely to change residences during the course of the research compared to other youth, and any relocation information likely depends on collaborative relationships with public agency staff, who may (intentionally or unintentionally) limit researcher access to updated information (Berrick et al, 2000). Indeed, Scott (2004) estimates that such “blocked access can create attrition rates as high as 50%, depending on the nature of the sample” (p. 32).…”