Fitzpatrick-Lewis et al. BMC Public Health 2011, 11:638 http://www.biomedcentral.com/1471-2458/11/638 full text screening for relevance. A total of 84 articles were deemed to be relevant and subsequently under- went quality assessment. Of the relevant studies, 0 were rated methodologically strong, 10 were moderate, and 74 were weak (see Figure 1). The most common reasons for a weak rating were high attrition, lack of assessor and/or participant blinding, and selection bias. Due to heterogeneity among the included studies in terms of interventions, study design, and outcomes, meta-analysis of the results was not appropriate. Results from the 10 studies that were rated to be of moderate methodologi- cal quality are summarized in detail below, with general findings from weak quality studies reported in lesser detail when appropriate, such as in the case of interven- tions for homeless women, families, and children in which neither strong nor moderate quality studies were found. Interventions for Homeless People with Mental Illness One randomized controlled study developed and tested an intervention to prevent homelessness among indivi- duals discharged from psychiatric wards to shelters and “no fixed address” [82] (see Table 2 for further study details). This pilot study followed 14 participants who were found to be at risk of homelessness during dis- charge planning. One half of the participants were pro- vided with immediate assistance in accessing housing, as well as assistance in paying their first and last month’s rent. The control group received usual care, which included a referral to a social worker but no assistance with finding or accessing housing. All the individuals in the intervention group maintained housed status at 3 and 6 months following hospital discharge. All but one participant in the control group remained homeless after 3 and 6 months (p < .001). Interventions for Homeless People with Substance Abuse Three studies evaluated programs for homeless persons with substance abuse issues (see Table 2). The first 331 EXCLUDED Reasons for exclusion: Studies did not include: • • • • 1, 546 ARTICLES RETRIEVED 415 FULL TEXT SCREENING 84 QUALITY ASSESSED 1, 131 NOT RELEVANT AT TITLE AND ABSTRACT Global quality rating includes: selection bias, study design, confounders, blinding, data collection 0 STRONG 10 MODERATE 74 WEAK Figure 1 Flowchart of included/excluded studies. Page 6 of 14 study [83] examined the effectiveness of the Housing First in Seattle, Washington, which targeted chronically homeless persons with severe alcohol problems and high health care use and costs. Housing First provided housing with on-site case management that encouraged participants to set goals related to substance use and other aspects of their lives. A quasi-experimental study design was used to compare individuals in the Housing First program (n = 95) and individuals in the program waiting list (n = 39) [83]. While this study reported on several outcomes, for this review the main outcomes of interest include: patterns of substance use and utiliza- tion of hospital-based medical services including detoxi- fication and treatment, and emergency medical services. The median number of drinks consumed decreased from 15.7 per day prior to housing to 14.0, 12.5, and 10.6 per day at 6, 9 and 12 months housed respectively (p = .003). Per-month use of medical services in the year prior to housing entry was compared with total use throughout the period of time the participant in the intervention group was housed. Utilization of various medical services decreased as the time housed for parti- cipants lengthened, with the median time housed being 17.2 months (specific risk reduction values not reported). A second study identified was reported in a series of reports with analyses of data at a number of time points [84-87]. This study examined the effectiveness of beha- vioural day treatment alone (DT; n = 69) versus beha- vioural day treatment with abstinence contingent housing and work therapy (DT+; n = 72) on housing, abstinence, and relapse outcomes in homeless indivi- duals. Abstinence was defined as either complete or par- tial, with both initially identified by ≥ 4 consecutive drug-free urine specimens, and complete abstinence referring to no drug use versus partial abstinence defined as the number of consecutive weeks of drug-free urine screens and drug use during not more than 1 con- secutive week [85]. Over a 24-week period, 82 and 93% of participants established abstinence in the DT and DT + groups, respectively. Of the 117 participants who established complete or partial abstinence, lapse (i.e., drug use during 1 week or less) was lower in the DT group than the DT+ group (45% vs 61%). Relapse, how- ever, (i.e., drug use in at least 2 consecutive weeks over the 24-week period) was considerably higher with DT compared to DT+ treatment (81% vs 55%). The number of mean days housed in the past 60 days increased by 16.2 days (SE = 3.5) in the DT group and 18.7 days (SE = 3.9) in DT+ from baseline to 12 months, with no dif- ference between treatments [86]. A third study examined several outcomes for homeless cocaine-dependent participants who received 6 months of cognitive behaviour day treatment with either no