TABLE 1.

Summary of Study Characteristics from Articles Included in the Systematic Review

Author(s) Publication Date	Sample Characteristics	Study Design	Definition of Homelessness	Date and Data collection	Recruitment
Noell et al. (2001)15	Sample size N = 536 Age (y) Females Range, 13–20 Mean, 17.7 Males Range, 14–20 Mean, 18.8 Gender 40.5% female 59.5% male Race/ethnicity 77% white 10.4% Native American Indian 3% Hispanic 2.8% black 1.1% Asian 5.7% other Orientation Not noted	RCT (baseline, 3 and 6 mo) 60.8% completed all 3 assessments (66.4% females, 57.1% males)	Spending more than 30 days total without parents or guardians in the previous 6 months, not living with parents or guardians, even temporarily, in the last 30 days, and not having a stable domicile	Method Face to face interviews (20–30 min) Incentive US $20 at baseline, US $30 at 3 mo, US $40 at 6 mo US $10–US $25 at monthly check-ins between assessments Collection Date 1994–1997 Location Streets of a large Northwestern city	Method Recruitment conducted in 3 separate successive waves Street observers conducted formative work Locations parks, street corners, parking lots, service agencies, and youth shelter
Rew et al. (2002)16	Sample size N = 414 Age, y Range, 16–20 Mean, 18.5 Gender 59% men 41% women Race/ethnicity 75.4% Anglo American Orientation 65% heterosexual 35% homosexual or bisexual	Exploratory design Convenience sample	Not Noted	Method Self-report Questionnaire Incentive US $10 Collection Date Not Noted Location Central Texas	Method Street outreach Location Street outreach program
Van Leeuwen et al. (2002)17	Sample size Not reported Age, y Not reported Gender Not reported Race/ethnicity Not reported Orientation Not reported	Cross-sectional Convenience sample	Not Reported	Method Survey (5–10 min) Incentive Transportation to STD clinic Collection Date Jan 2000 to Apr 2002 Location Denver, CO	Method Outreach workers recruited youth Location Park popular with homeless youth
Beech et al. (2003)18	Sample size N = 125 Age, y Range, 14–23 Gender 70% male 30% female Race/ethnicity 37% AA 42% white 21% Hispanic, American Indian, or Biracial Orientation Not noted	Cross-sectional	Not Reported	Method Face to face interviews (20 min) Incentive Undisclosed monetary compensation Collection Date Not Reported Location Large Southwest city	Method Outreach workers recruited youth from shelters, temporary facilities, and street-based using a snowball sampling method over a 2-week period Location Not Reported
Halcon and Lifson (2004)19	Sample size N = 203 Age, y Range, 15–22 Mean, 19.2 for males and 18.4 for females Gender 40.4% female 59.6% male Race/ethnicity 47% white 27.7% AA 25.3% other “Other” 5% Hispanic 4% Asian/Pacific Islander 9% Native American 8% more than one racial/ethnic category Orientation Not noted	Cross-sectional Community-based sampling	Homeless at least 1 mo in the past year, during which time homeless at least half of those days, able to give informed consent	Method Face to face interviews (20–30 min) Incentive US $20 vouchers Collection Date 1998–1999 Location Minneapolis, MN	Method Outreach workers recruited youth Locations Coffee shops, restaurants, parks, meal-serving sites river/railroad tracks,
Rew et al. (2005)20	Sample size N = 425 Age, y Range, 16–20 Gender 58% males 42% females Race/ethnicity Not noted	Secondary analysis Nonprobability sample	Not Noted	Method Self-report Questionnaire Incentive US $10 Collection Date Not Noted Location Urban, south central US	Method Street outreach Location Street outreach program
Solorio et al. (2006)21	Sample size N = 261 Age, y Range, 12–20 Mean, 15.4 Gender 60% female Race/ethnicity 44% Latino 23% AA 20% White 13% mixed race Orientation 84% heterosexual	Cross-sectional Subsample of a larger, longitudinal study	Spent at least 2 consecutive nights but less than 6 months away from home without parent/guardian’s consent or if under 17 years, been told to leave their home	Method Face to face interviews (1 hr) Incentive US $20 Cash Collection Date 2001–2002 Location Los Angeles County, CA	Method Interviewers sent to predetermined sites to recruit youth Locations Shelters, drop-in centers, street hang-outs
Buffardi et al. (2008)22	Sample size N = 90,000 participated in school-based survey n = 20,748 also completed more detailed questionnaire n = 15,197 completed computer-assisted survey n = 14,012 provided urine for STD testing Gender Not noted Age, y 18–27 Race/ethnicity Not noted Orientation Not noted	Stratified, school-based random sampling	Not Noted	Method School-based survey, in-home questionnaire, computer-assisted survey Incentive Not Noted Collection Date 1994 July 2001-April 2002 Location United States	Method National Longitudinal Study of Adolescent Health Location Not Noted
Tevendale et al. (2009)23	Sample size N = 302 Gender 55.7% male 44.3% female Age, y 14–21 Mean, 18.8 Race/ethnicity 19.8% White 24.5% African American 25.0% Hispanic/Latino 25.0% Mixed 5.7% Other Orientation Not noted	Cross-sectional study	Not Noted	Method Audio computer-administered self-interview survey (1.5 h) Incentive US $20 Collection Date 2004–2005 Location Los Angeles County, CA	Method Field interviewers recruited youth Location Drop-in centers and shelters
Valente and Auerswald (2013)24	Sample size N =258 Age, y Range: 15–24 Median: male, 21 female, 20 Gender 64% male 36% female Race/ethnicity 54.5% white 45.5% nonwhite	Cross-sectional study Venue-based sampling Substudy of a larger, longitudinal study San Francisco	Having to stay 2 or more nights at a place that is not your home or homeless in the prior 6 months	Method Audio computer-administered self-interview survey (30–45 min) and article-based social network survey (15 min) Incentive US $20 Survey US $10 STD testing Collection date Not Noted Location San Francisco, CA	Method Outreach workers recruited youth Location Street venues, transitional housing programs