of orthopedic impairment were cited, which represents 16.8 percent of all conditions affecting work capacity. Other impairments that were common causes of work limitation included visual impairments (mentioned 580,000 times), paralysis (552,000 times), and learning disabilities or mental retardation (546,000 times).
In excess of 22.7 million cases of disease or disorder were reported to contribute to work limitations, representing 72.5 percent of all conditions contributing to such limitations. The most common diseases and disorders contributing to work limitations include musculoskeletal and connective tissue disorders (5.4 million individuals), circulatory diseases (5.1 million individuals), and nervous system and sensory organ conditions (2.1 million individuals).
Impairment and Daily Life Finally, Table 2-2 indicates the number of conditions contributing to limitations in ADL or IADL and the proportion of all such limitations associated with each major classification of impairment or disease or disorder. The data concerning ADL or IADL limitations are limited to persons age 5 years or older. In 1992, in excess of 9.2 million individuals indicated that they had conditions that contributed to ADL or IADL limitations. Of these, 2.3 million (about 25 percent of all people with conditions contributing to ADL and IADL limitations) had impairments that contributed to ADL and IADL limitations. A total of 988,000 individuals had orthopedic impairments that contributed to ADL or IADL limitations; other impairments mentioned included learning disabilities or mental retardation (399,000 individuals), paralysis (278,000 individuals), and visual impairment (254,000 individuals). All forms of diseases or disorders contributed to ADL or IADL limitations in more than 22.7 million individuals, or roughly 3/4 of the total. The most common major disease classifications contributing to this form of limitation included musculoskeletal and connective tissue disorders (1.9 million individuals), circulatory conditions (1.6 million individuals), and nervous system and sensory organ conditions (884,000 individuals).
Prevalence of Activity Limitation in Children Among children under the age of 18 years, an estimated 4.0 million (6.1 percent of the U.S. population under the age of 18 years) have some type of disabling condition.* Disability in this age group is defined differently from disability in adults and includes any limitation in activity due to a chronic health
The committee believes that, given the potential for effective interventions that can enable people with disabling conditions, most of these conditions should be strictly defined as potentially disabling conditions. For the sake of readability, however, we use the term disabling condition throughout this report with the intent that ''potentially" is understood.