Rosenhan

Aim: To prove hypothesis that psychiatric diagnosis is neither reliable nor valid.

Study one: 

• Field experiment
• eight sane people (friends of Rosenhan),
• claimed they were hearing words Thud Hollow Empty,
• used false names
• collected notes on their experience and how hospital staff interacted with patients.
• All but one amitted with diagnosis of Schizophrenia.

Results:

Stayed in hospital for mean of 19 days, Very little contact with hospital staff, Psuedopatients making notes was thought as "abnormal writing behaviour"

Staff are making TYPE 2 ERROR - (diagnosing a healthy person as sick)

Aim: In the secondary study, the staff of a teaching and research hospital, which was aware of the first study, was falsely informed that during the next three months one or more pseudo patients would attempt to be admitted into their hospital.

Results:

• 193 patients were rated - 41 suspected of being psuedo patients
• no psuedo patients were actually sent
• Staff are making TYPE 1 ERROR - (diagnosing a sick person as healthy)

Conclusions:

Demonstartes that psychiatrists cannot reliably tell the differnece between sane and insane individuals.

Type 2 error was made in experiment 1 and Type 1 error was made in experiment 2