In this section, we briefly review how homeless youth have been studied in the past and what is known about homeless youth from this research (for amore comprehensive review, see Robertson & Toro, 1999).
Haber and Toro (2004) describe four basic approaches used by researchers to sample homeless youth. The first approach is to survey large groups of youth in the general population and identify those with a history of homelessness (e.g., Ringwalt et al., 1998; Windle, 1989). These methods may misrepresent the total homeless youth population because they do not include youth who are currently homeless, who may well have longer histories of homelessness and other negative characteristics. The second draws youth from service settings such as inner-city clinics (Kipke, Montgomery, & MacKenzie, 1993; Yateset al., 1988). Of course, youth seeking services may be different from those who do not seek help. The third approach samples youth from shelters (e.g.,McCaskill, Toro, & Wolfe, 1998). Some of the youth these facilities serve have been brought to the shelter by their families or third parties such as the police. Many have never spent a night on the streets. Such youth are often younger and less likely to have extensive histories of homelessness than street youth (Robertson & Toro, 1999). The fourth approach involves sampling from street locations where homeless youth are known to congregate and/or from drop-in centers designed to serve street youth (e.g., Cauce et al., 1994; Kipke, O’Connor, Palmer, & MacKenzie, 1995; Roy et al.,1998). This method often yields a sample biased toward youth who are engaged in a variety of deviant behaviors, especially if the sample includes many youth who are 18 or older. Some recent studies have combined the four methods in an effort to obtain more representative samples (e.g., Heinze, Toro, & Urberg, 2004; Paradise et al., 2001; Toro & Goldstein, 2000; Unger et al., 1998; Whitbeck, Hoyt, & Yoder, 1999; Witken et al., 2005).