The use of personality tools in the workplace is worthy of a considered exploration of the nuance between different types of tools and different uses of these tools. This would be much more useful for people working in organizations and looking to effectively use personality assessments. Should the MBTI indicator be used in selection? Absolutely not. Does the MBTI instrument have evidence of validity for self-awareness and development? It certainly does.
For those of us using the MBTI in developmental applications, rest assured; we are using a reliable instrument in a valid way. Here is some information on reliability:
- Test-retest correlations up to 15 weeks for the most recent version of the Myers-Briggs instrument average .87 for the four scales, indicating good reliability for each preference over long periods of time. The general standard for a scale on any psychometric assessment is to have an internal consistency reliability of .70 or above.
- Reliability based on employment status: Reliability across five employment statuses – employed full-time, employed part-time, full-time student, retired, and not working for income – are high, ranging from .86 to .92, indicating that the Myers-Briggs instrument is reliable across a variety of employment situations.
- Reliability across ethnicity: The reliabilities are high, ranging from .80 to .92, and are similar across the nine ethnic groups, suggesting that the Myers-Briggs Form M assessment is reliable across a range of ethnic groups.
Here is some information on validity of the MBTI instrument.
- The Myers-Briggs Company publishes a freely available and recently updated MBTI Form M Manual Supplement containing data on the various validations of the instrument.
- Isabel Briggs Myers worked with Educational Testing Service in Princeton, NJ, a major test publisher, in developing the instrument. ETS was its first publisher (as a research instrument) in 1962. Twenty years of research preceded its initial 1962 publication.
- The instrument is updated regularly based on continuing research, and the Myers-Briggs conforms to all the requirements for educational and psychological tests.
- Five technical manuals and supplements have been published—1962, 1985, 1998, 2009 and 2018, providing a wealth of research-based evidence on its reliability and validity.
- Here are more frequently asked questions and detailed answers, including links to outside research for reliability and validity.