The 2008-09 NSYC survey consisted of an audio computer-assisted self-interview (ACASI) in which youth, using a touch-screen, interacted with a computerized questionnaire and followed audio instructions delivered via headphones. The NSYC utilized self-administered procedures to ensure the confidentiality of the reporting youths and to encourage fuller reporting of victimization. The survey made use of audio technology to provide assistance to youth with varying levels of literacy and language skills. Approximately 98% of the interviews were conducted in English; 2% in Spanish.

Administrators in each state, county, and private facility determined the type of consent required for youths to be eligible for participation. Administrators provided in loco parentis (ILP) consent in 63 facilities. In loco parentis is when administrators provide consent “in the place of the parent” to contact youth. In the remaining 132 facilities, administrators required consent from the youths’ parents or guardians (PGC). Youth in all facilities also had to assent to participate in the interview.

In each sampled PGC facility, administrators were asked 8 weeks prior to data collection to provide a roster of all adjudicated youth assigned a bed; in ILP facilities a roster was provided 4 weeks prior to data collection.

All youth were sampled in ILP facilities and in PGC facilities with 240 or fewer youth on the roster. In larger PGC facilities, all females and a random sample of males were selected. In both PGC and ILP facilities all incoming youth were added to the sample up to 4 weeks prior to the survey. Youth who had been present in the facility at least 4 weeks prior to the survey and were present at the time of the survey were considered eligible.

The result of this process yielded a sample representing 26,551 adjudicated youth held nationwide in state operated and large locally or privately operated juvenile facilities. A total of 10,263 youth participated in the survey. Of these, 1,065 received an alternative survey on drug and alcohol use and treatment, and 9,198 youth participated in the survey of sexual victimization.