Special Studies


Alan Cowles, M.D., Ph.D. is a medical consultant with the Kansas State Disability Determination Services. He is an expert on the content and application of the "disability listings" for the Social Security (Title II) and Supplemental Security Income (Title XVI or SSI) disability programs. The Listings are a set of medical conditions that are presumed to be incompatible with engaging in substantial gainful activity. Persons whose conditions meet the requirements of one or more listings are normally determined to be disabled at an early step in the disability evaluation process. The listings therefore may be considered to be administrative shortcuts to granting disability benefits.

Dr. Cowles has undertaken an historical study of the development the Listings, and produced an in-depth study of that history. His study is being made available here, as it contains useful documentation of historical developments related to the disability listings and the disability program.

The views expressed in this article are those of Dr. Cowles and are not official policy statements of the Social Security Administration or of any other agency of government.


A History of the Disability Listings- by Dr. Alan Cowles (pdf format file).