After culling data from presidential biographies, Davidson was joined by Kathryn Connor, associate professor of psychiatry, and Marvin Swartz, professor and head of the social and community division of psychiatry, to analyze the information. Together, they diagnosed the commander-in-chiefs from 1776 to 1974.
According to the study, published in January in the Journal of Nervous and Mental Disease, of the 37 presidents researched, 18 were found to suffer a mental illness of some form. Depression was the most prevalent disorder among presidents, occurring at a rate of 24 percent.
Some of them are as simple as social phobia:
Though Calvin Coolidge's hypochondria may not have had the most profound effect on affairs of state, Coolidge, Grant and Thomas Jefferson were diagnosed with social phobia by Davidson and his associates.
What do you think?
"Social phobia is kind of remarkable in a president. It meant he was shy and avoided social circumstances, and yet he was president," Swartz said.
Yet, this concluded that this didn't affect the country:
The study noted among its implications that no national calamities seem to have been a result of presidential mental illness.