Similar comments have been raised about the MMPI. On a quick look again, I found: https://www.minnpost.com/second-opinion/2009/08/fascinating-tale-about-us-mm

Similar comments have been raised about the MMPI. On a quick look again, I found: https://www.minnpost.com/second-opinion/2009/08/fascinating-tale-about-us-mmpi-controversy https://www.minnpost.com/second-opinion/2009/08/fascinating-... he original developers of the MMPI questionnaire went about choosing their "normal" control group. They compared test answers from patients in hospitals for the mentally ill with answers from people working in and visiting those hospitals. Who’s to say those workers and visitors were mentally healthy? It's well known that certain kinds of mentally ill people are drawn to working in the mental health industry. I know a psychiatrist who's a narcissist, and a psychiatric nurse who's probably BPD or NPD. Bootstrapping a test from a hand-picked set of people is just bad methodology.