Paul Meehl has suggested that when clinicians mistakenly pay attention to vague, superficial, or stereotyped statements by clients, and fail to pay to attention to subtler but more important evidence, they are victims of the cognitive error he has labeled the Barnum effect.
Barnum Effect, also called Forer Effect, is term used in psychology.
It denotes the phenomenon that occurs when individuals believe that personality descriptions apply specifically to them, and actually they are not.