Twenty-nine studies were included in the review (n = 30,427): four RCTs (n = 231): 13 prospective cohort studies (n = 2,610); two retrospective cohorts (20,335); four quasi-experimental studies (n = 3,533); and six cross-sectional studies (n = 3,718).
Healthcare utilisation (14 studies including two RCTs): the evidence base for housing interventions for individuals with SPMI who were identified as homeless at hospital admission was considered good. One RCT and one cohort study with matched control group found that housing placements were associated with reduced hospital admissions and fewer days of hospitalisation than control conditions.
The evidence base for the effectiveness of housing interventions for individuals with SPMI who were not identified as homeless was considered weak, although three prospective cohort studies reported fewer mean days of hospitalisation in the year following a housing intervention than in the previous year, while two other cohort studies found stable or affordable housing significantly reduced length of hospitalisations although number of hospitalisations was not affected.
Mental status outcomes (12 studies, including one RCT): the single RCT found that there was no difference in levels of psychiatric symptoms between a group whose housing placement required psychiatric treatment compliance and sobriety, and one without such contingency. Other studies suggested that the duration rather than the nature of housing provision may be the key determinant of mental health effects.
Quality of life (nine studies, including one RCT): the single RCT compared group homes with independent apartments and found that total neuropsychological functioning improved in both groups but that executive function sub scores decreased significantly in participants housed in independent apartments, while quality of life outcomes were not affected by the intervention in either group.