Disability Evaluation Under Social Security

Disability Evaluation Under Social Security describes the Social Security Administration criteria for determining if a person is disabled and therefore eligible for 1) the Social Security disability insurance program under Title II of the Social Security Act and/or 2) the Supplemental Security Income (SSI) program under Title XVI of the Act. The SSA criteria for determining disability may not be the same as the disability criteria for other government or private disability programs.

Under Title II and for adults applying under title XVI, the definition of disability is “the inability to engage in any substantial gainful activity (SGA) by reason of any medically determinable physical or mental impairment(s) which can be expected to result in death or which has lasted or can be expected to last for a continuous period of not less than 12 months.”

Under title XVI, the definition of disability for a child under age 18 is the presence of “a medically determinable physical or mental impairment or combination of impairments that causes marked and severe functional limitations and that can be expected to cause death or that has lasted or can be expected to last for a continuous period of not less than 12 months.”

Disability Evaluation Under Social Security (formerly "The Blue Book") provides information on the disability process, state disability determination services and documentation of an impairment, as well as listings of impairments for children and adults, questions and answers about Social Security disability programs and more. This publication was formerly known as "The Blue Book" and is no longer published in hard copy.

For additional reading, see our page on Social Security Administration in the A-Z Glossary, as well as SSA's Red Book which describes SSA employment supports for people with disabilities.