Estos son algunos de los estudios, correlaciones y validaciones realizadas por universidades:

• Randall, Stephen “Development of an Inventory to Assess Enneagram Personality Type” California Institute of Integral Studies GAX80-05160

• Wagner, Jerome “A descriptive, ralibbility, and validity study of the Enneagram Personality Typology” Loyola University GAX 81-09973”

• Wagner, J. P. and Walker, R. E. “Reliability and validity study of a Sufi personality typology: The enneagram.” J. Clin. Psychol., 39: 712–717. Department of Psychology, Loyola University.

Links con información y algunas investigaciones:

http://onlinelibrary.wiley.com/doi/10.1002/1097-4679(198309)39:5%3C712::AID-JCLP2270390511%3E3.0.CO;2-3/abstract

http://udini.proquest.com/view/an-analysis-of-the-validity-of-the-pqid:2425450421/