A study by American Psychologist Rosenhan "On being sane in insane places" demonstrated that psychiatrists cannot reliably distinguish between people with a genuine mental illness and people pretending to have one. Rosenhan sent accomplices to Hospitals, all with the instruction that they complain of one symptom, hearing the word "Thump". All were institutionalized and labeled as being sufferers of a variety of conditions "in remission" upon their discharge. There was much fury from the psychiatric establishment when these results were made public. One psychiatrist challenged Rosenhan to send accomplices again, confident that he could spot them. Rosenhan agreed, and some time later the psychiatrist proudly contacted Rosenhan in the belief that he had found them all, to which Rosenhan responded that he hadn't sent a single one that time. Rosenhans' term for persons in a situation of being mistaken for insane was "pseudopatient"and the subtext of his study is that any social faux pas, intentional or not, could be misinterpreted as a psychiatric symptom by a psychiatrist.
According to the Adam Curtis documentary "The Trap: What happened to our dream of freedom?" the NHS, and other public services, under New Labour introduced a system of targets to motivate staff, in line with the theories of John Nash as interpreted by Alain Enthoeven. The documentary highlights the problem that staff could simply falsify the paperwork to create the illusion of targets being met in order to keep their jobs. This would include misdiagnosing someone. John Nash had schizophrenia.
Someone believing themselves to have been misdiagnosed faces a "Catch-22" situation: complaining about a diagnosis can be interpreted as another symptom of the diagnosis, as for example "delusion of persecution", "attention-seeking", "circumstantiality", "flight of ideas", "neologism", "latent aggression", "religiosity", "lack of insight", "oppositional defiance", "echolalia", "coprolalia" or "grandiosity".
The NHS has provided Chaplains to work in Mental Hospitals alongside Doctors who regard religious belief as a symptom. There have been Mental Hospitals with whole Chapel Buildings built on the grounds, and with piles of evangelical leaflets in the wards.
NHS Mental Health Services are underfunded relative to the prevalence of conditions. Mental Illness Conditions are underdiagnosed.