Twenty-four month data were available for 314 of 426 (74%) newly homeless youth; 183 youth from Los Angeles County (70%) and 131 youth from Melbourne (79%). Baseline refusal rates were less than 7% in the United States and not evaluated in Australia. Based on the baseline sample size, follow-up rates were 83%, 87%, 82%, 81% and 70% in Los Angeles for the 3-, 6-, 12-, 18- and 24-month interviews, respectively; and 72%, 85%, 86%, 82% and 79% in Melbourne. These rates are quite high for a sample of homeless youth, who tend to be difficult to track over time. Most youth who were lost to follow up moved out of state and therefore were inaccessible to the research team. Across sites, there were more females (60%) than males (40%). Of the youth who completed a 24-month assessment, the age at baseline ranged from 12 to 20, with 19% between 12 and 14, 62% between 15 and 17, and 19% between 18 and 20. In Los Angeles County, 17% were White (non-Hispanic), 21% were African-American, 47% were Hispanic, and 15% were of other races/ethnicities.
summarizes the rates of risky behaviors reported for the previous three months at the time of the two-year follow-up assessment, which constitute our primary outcome measures. The number of recent sexual partners, presented in categories because of the high skewness, was significantly higher in females compared with males (χ2 = 16.9, P < .001), but not significantly associated with site or age. Youth in Los Angeles County were more likely to be abstinent than those in Melbourne in the three months prior to the two-year follow-up interview (χ2 = 7.3, P < .01), and males were significantly more likely than their female peers to be abstinent (χ2 = 8.1, P < .01). Among sexually active adolescents, condom use was similar by country and age, but varied significantly by gender. Males were significantly more likely to always use a condom than females (χ2 = 5.7, P < .05). The pattern of condom use was similar across countries.
Sex and drug risk variables at 24 months by site, gender, and age
Injection drug use was significantly higher in Melbourne compared to Los Angeles County (χ2 = 5.3, P < .05); this finding was present at the time of the initial recruitment and continued over the two-year follow-up period. Similarly, hard drug use was significantly higher in Melbourne compared to Los Angeles County (χ2 = 4.2, P < .05), but was similar among males and females and across age groups. A significantly higher percentage of Melbourne youth reported using only alcohol and marijuana compared to Los Angeles County (χ2 = 4.6, P < .05), although there was no significant difference across gender and age groups.
describes the youth's living situation over their lifetime, prior to leaving home and over the two-year follow-up period; variables measure housing stability. Over their lifetime, newly homeless youth in Melbourne experienced a significantly greater number of moves compared to youth in Los Angeles County (χ2 = 44.6, P < .0001). More than 70% of the Melbourne youth experienced five or more moves and one in four moved 10 or more times over their lifetime. Only 37% of Los Angeles County youth reported five or more moves and a very small percentage had moved 10 times (4.9%).
Predictor variables: living situation and housing stability by site, gender, and age
Although the living situations of the Melbourne youth were far less stable prior to recruitment, the number of moves was similar across sites, gender, and age in the two years following becoming newly homeless. Los Angeles County youth were significantly more likely to return and stay home than Melbourne youth (χ2 = 36.4, P < .0001): 16.4% returned home quickly and remained there for the next two years, and another 25.7% remained home for more than a year. Only 1.5% of Melbourne youth returned home and stayed there over two years and only 15.3% were at home for a year. Across sites, younger youth were significantly more likely to return home than older youth (χ2 = 39.4, P < .0001). Of youth aged 18–20 years at recruitment, 56% never returned home over the next two years, while 87% of youth under age 15 returned home over the next two years. More Melbourne youth were likely to be in institutional placements over the follow-up period (χ2 = 15.0, P < .001), with older youth significantly more likely to be in institutional settings than their younger peers (χ2 = 10.0, P < .05).
details the results of the multivariate regression analyses. We analyzed three primary outcome measures: number of sexual partners at 24 month follow up, condom use in the 90 days prior to 24 month follow up, and drug use in the 90 days prior to 24 month follow up. Controlling for site, gender, and age, there was not a significant relationship between the number of sexual partners with housing stability or type of living situation. Condom use was predicted by sociodemographic characteristics, with males using condoms significantly more often than females (OR = 1.84, χ2 = 4.17, P < .05). The number of placements in institutional settings was also significantly related to higher condom use (χ2 = 6.94, P < .01). The sociodemographic characteristics and housing factors significantly predicted drug use at two years (omnibus χ2 = 68.7, P < .0001). Drug use at 24 months was significantly associated with drug use at baseline (χ2 = 12.7, P < .001 for alcohol/marijuana use; χ2 = 30.3, P < .0001 for hard drug use; and χ2 = 22.4, P < .0001 for injecting drug use). Site was also significantly associated with drug use (OR = 0.38; χ2 = 12.6, P < .001), indicating that Melbourne youth were significantly more likely to use drugs than youth in Los Angeles over the two-year period. Accounting for sociodemographic variables and baseline drug use, drug use at 24 months was related to the number of moves (χ2 = 4.0, P < .05). The more moves a youth made over the two-year follow-up period, the more likely they were to have used serious drugs.
Multivariate regressions on risk outcomes