Demography of family households.

A profile of the demography of individuals with mental retardation and related developmental disabilities (MR/DD) was developed from the Survey of Income and Program Participation, a national household survey. We estimated a total 1991 population of 2.97 million Americans with MR/DD, with 2.63 million living outside the formal long-term care system. Observations suggest that (a) families are the dominant form of support and, thus, a key constituency in disability policy; (b) a large cohort currently live in households headed by aging family members; and (c) there are significant economic disparities between subgroups of families, defined primarily along gender and racial lines.