The literature review in Chapter 2 identifies key knowledge, as well as gaps in that knowledge, related to homeless families and families at risk of homelessness that will be critical to the development of a relevant typology for the purposes of this study. While there is a considerable amount known about currently homeless families and their needs, there are also significant gaps in the knowledge because of limitations in population coverage (focus on the currently homeless and small samples that do not permit subgroup analysis), the cross-sectional nature of many of the studies, the lack of focus on intervention, and the lack of data on children (Table 4-1).
The lack of comprehensive population coverage in previous studies is due to several factors, including a dominant focus on currently homeless families, relatively small study sample sizes, and a concentration of research in East Coast cities. The focus on currently homeless families provides an understanding of the characteristics of those who become homeless, but generally explains little about families prior to entering homelessness (and, even then, only retrospectively) and does not provide any knowledge of the specific subgroups of the broader population who may be at risk of homelessness. In addition, because only a few studies have tracked homeless families for 12 months or longer, little information is available on families after they leave shelter or about their long-term stability.
The small study samples generally inhibit the ability to examine specific subgroups. For example, survey questions may be asked about families who are currently working but, because the percentage of working families in currently homeless samples is typically 20 percent or less, the overall study samples are generally not large enough (e.g., 500 or more) to provide subsamples of sufficient size. Other key subgroups with inadequate sample sizes in current studies include those who are episodically homeless (because they are homeless for such short periods of time and generally are not represented in studies with restricted recruitment patterns or with criteria that require a minimum period of homelessness before being included in the study); families with two parents; moderate-need families; families living in extended family networks; and chronically homeless families. Although one study (Burt, M., Aron, L.Y., Douglas, T., Valente, J., Lee, E., and Iwen, B., 1999) had a large sample of families, only limited information on the families was collected because it was part of a larger effort.
A final limitation with respect to population coverage is the fact that many studies concentrated their data collection in East Coast cities. Because of the contextual nature of homelessness and the diversity in labor markets, housing markets, and service systems, the lack of attention to other geographic areas of the country-especially the Midwest, South, and rural areas-limits the generalizability of the findings and would likely distort any typology efforts that were based solely on existing data.
Although a few past studies had longitudinal study designs, only one study tracks families over a 5-year period and even then only two waves of data were collected. Longitudinal, ongoing data on families who have experienced homelessness would increase the understanding of the course of residential instability and homelessness and the factors that influence this course (including individual, contextual, and intervention factors).
There is also a paucity of data on the role of prevention efforts in keeping families from becoming homeless and intervention efforts to help them exit homelessness. Finally, most of what is understood about homeless families is either about the mother or from the mother's perspective; few studies have focused on the children in the families.
Most of the data that is available on homeless families has been drawn from research studies that focus exclusively on homeless families, as opposed to the population at large or even studies that have explored the needs of low-income families or families living in poverty. A number of existing data sets that include low-income families potentially contain information to support the development of a typology of homeless families. In order to be useful, a data set must include information on each family's housing status or housing history to determine if the family is or has been at risk of homelessness or has experienced homelessness.
This chapter summarizes our review of data sets that focus on or include low-income families (i.e., families who have the greatest probability of experiencing housing instability), including the stepwise approach taken to identify and screen the data sets to determine if they have the necessary housing information. The purpose of this undertaking was to identify existing prospects for secondary analysis-that is, data already being collected that could serve to inform the development of a homeless family typology. Project staff examined major national or multijurisdictional surveys that might include large numbers of low-income respondents (e.g., potentially homeless or homeless families) and the types of data currently being collected. This chapter highlights what can and cannot be answered with existing data.