When a hospital he punked complained about his claims of misdiagnosis, Rosenhan engineered a further test of the hospital’s powers of psychiatric diagnosis: He promised to send a number of fake patients to the hospital over the course of three months. During this time, the hospital evaluated 193 total patients. They labeled 41 of these patients as imposters and considered another 42 patients suspect.
In fact, Rosenhan hadn’t sent any fake patients at all.
Critics of Rosenhan’s experiments point out that psychiatric diagnosis depends on self-reporting. Perhaps a person who misreports hearing voices is as delusional and in need of treatment as the person who does, in fact, hear voices.