Homeless Mentally Ill:

Problems and Options in Estimating Numbers and Trends

PEMD-88-24: Published: Aug 3, 1988. Publicly Released: Sep 8, 1988.

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In response to a congressional request, GAO examined the methodologies of current population estimates of the number of homeless chronically mentally ill persons to: (1) determine the soundness of current estimates; and (2) identify the best available methods for getting sound estimates.

GAO found that: (1) although there were no sound national estimates of the number of homeless persons who were chronically mentally ill, there were some relatively sound local estimates on both homeless persons and the chronically mentally ill; (2) while the estimates would not apply nationally, the methods used were applicable on a larger scale; (3) many of the estimates had methodological flaws associated with a high degree of uncertainty or bias that could lead to underestimates or overestimates; (4) of the 10 studies that GAO rated technically sound, 9 were based on surveys or censes and one was based on utilization data; (5) the rates of homelessness ranged between 6 and 95 per 10,000 in the study communities and were related to the quality of methodology; (6) analysis of a methodology judged to be of a higher quality lowered the range by almost half; (7) the proportion of homeless persons identified as mentally ill was between one-fifth and one-third, in the judgment of service providers, and between one-sixth and one-half using standardized instruments; and (8) because the definition of homelessness varies and homelessness itself could contribute to behavior and appearances that suggest mental illness, counting homeless mentally ill persons is never entirely precise.

Matter for Congressional Consideration

  1. Status: Closed - Not Implemented

    Comments: Congress has no plans to look at these issues in the near future.

    Matter: Congress should continue the effort to better define and validly measure mental illness among homeless persons.

Recommendation for Executive Action

  1. Status: Closed - Not Implemented

    Comments: The Department of Health and Human Services does not believe that it can go beyond the requirements set by the McKinney Act, and does not plan further action.

    Recommendation: The Secretary of Health and Human Services should reexamine the requirements for data collection and evaluation by the states in the Stewart B. McKinney Homeless Assistance Act of 1987 (Public Law 100-77) and direct that the approaches outlined be incorporated when administrative databases are established and as regulations specifying data to be collected by grantees are prepared. These include such issues as a consistent definition of homelessness, specification of the area of coverage, obtaining data on a regular basis so that seasonality can be assessed, and supporting studies that would permit firmer adjustments for street-to-shelter ratios. The Secretary should also take steps to ensure that efforts continue to better define and validly measure mental illness among homeless persons, including an assessment of whether further research support is needed.

    Agency Affected: Department of Health and Human Services


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