1. A computer implemented method of generating a diagnostic tool by applying artificial intelligence to an instrument for diagnosis of a disorder, wherein the instrument comprises a full set of diagnostic items, the computer implemented method comprising: on a computer system having one or more processors and a memory storing one or more computer programs for execution by the one or more processors, the one or more computer programs including instructions for: testing diagnostic items from the instrument using a technique using artificial intelligence; determining from the testing the most statistically accurate set of diagnostic items from the instrument; selecting a set of the most statistically accurate diagnostic items from the instrument; determining the accuracy of the set of the most statistically accurate diagnostic items from the instrument by testing the set of the most statistically accurate diagnostic items from the instrument against an independent source; and generating the diagnostic tool for diagnosis of the disorder.