Making Sense of the MBTI–Enneagram Debate (part 2)

Author: Lisi Mallinson

Building on part one, where we explored the Enneagram’s scientific limitations and ethical considerations, this article turns to the MBTI itself.

The MBTI is a tool with decades of refinement, extensive research, and clear psychometric evidence, making it a secure and responsible choice for ethical practice. Common critiques of the MBTI often stem from a misunderstanding of its intended purpose, the methodology that underpins its utility or from confusion with unverified "free" online copies.

Let’s recap some of the basics: The methodology

The MBTI, as mentioned, is based on Jungian trait theory of preferences. The items in the MBTI are forced choice or ipsative in nature. The significance of using ipsative data in a personality instrument like the MBTI lies in this forced-choice format, which compels a respondent to prioritise preferences. However, this format introduces specific limitations and dictates how the assessment should be interpreted and applied.

What is ipsative data?

Ipsative data (from the Latin ipse, meaning "self") refers to measurements that compare traits within the same individual (intra-individual). In a personality assessment, the respondent is typically presented with two or more statements and must choose the one that is most or least characteristic of them.

Why is this significant? This format forces a trade off or prioritisation. It measures the relative strength of one preference (e.g. Introversion) against another (e.g. Extraversion) within the person, directly revealing the individual's "best-fit" type or dominant preference. For the MBTI, this is crucial as it focuses on psychological preferences (like being right- or left-handed) rather than the amount of a trait.

Proper use and interpretation

The distinct nature of ipsative data requires specific rules for proper use:

1. Focus on development, not selection: Ipsative data is primarily for developmental feedback, self-awareness, and understanding team dynamics. Because the scores only reflect internal comparisons, they are unsuitable for selection decisions (i.e. comparing one candidate to another or to a job profile). The MBTI itself is explicitly designed and sold as a developmental tool.

2. Highlight relative strengths: Scores should be interpreted as indicating a person’s preferred way of operating, thinking, or making decisions (e.g. Introversion preference over Extraversion). The data shows how a person manages their own psychological resources, not how much of a trait they possess compared to the general population.

3. Use guided feedback: The score is a starting point. Proper use of an ipsative tool like the MBTI requires a guided feedback process with a trained practitioner. This helps the respondent clarify their "best-fit type", acknowledges the natural use of their non-preferred options, and mitigates the risk of "putting people in a box".

Limitations of ipsative data

While powerful for internal insight, ipsative data has crucial limitations related to comparison and statistical analysis:

• Cannot compare across individuals: Ipsative scores are not normative. If Person A and Person B both score a high preference for Trait X, we only know that Trait X is their relative preference. We cannot say that Person A has more of Trait X than Person B, or even that their preference for X is stronger.

• Cannot compare across scales: Because the total score across all scales is often a constant (or nearly so), the scores are interdependent. An increase in one scale must result in a decrease in another. This interdependence limits the utility of standard statistical techniques, such as factor analysis and correlating scores with external criteria (like job performance), making it difficult to establish certain types of validity.

Best applications for ipsative data (the MBTI context)

Ipsative data is best applied in contexts where the goal is understanding internal priorities and facilitating growth:

In conclusion, the MBTI's transparent, well-documented, and consistent scientific properties allow us to meet our ethical and legal obligations as registered professionals.

To learn more about the MBTI’s psychometric properties and other relevant studies pertaining to the MBTI, see MBTI reliability and validity info.

References

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Department of Health. (2006). Rules of conduct pertaining specifically to the profession of psychology (Form 223, Annexure 12 of the Ethical Rules of Conduct for Practitioners Registered under the Health Professions Act, 1974). Government Notice No. R. 717. Government Printers.

Hook, J. N., Hall, T. W., Davis, D. E., Van Tongeren, D. R., & Conner, M. (2020). The Enneagram: A systematic review of the literature and directions for future research. Journal of Clinical Psychology, 77(4), 865–883. https://doi.org/10.1002/jclp.23097

McLean, James & Chissom, Brad. (1986). Multivariate analysis of ipsative data: Problems and solutions. https://www.researchgate.net/publication/234705458_Multivariate_ Analysis_of_Ipsative_Data_Problems_and_Solutions

Neuroscience News. (2025, August 24). Personality tests like Myers-Briggs can mislead more than reveal. Neuroscience News. https://neurosciencenews.com/personality-tests-unreliable-29609/

Riso, D. R., & Hudson, R. (1999). The wisdom of the Enneagram: The complete guide to psychological and spiritual growth for the nine personality types. Bantam Books Inc.

South African Government. (1998). Employment Equity Act, No. 55 of 1998. Government Printers.

Van Eijnatten, F. M., Van Der Ark, L. A., & Holloway, S. S. (2014). Ipsative measurement and the analysis of organizational values: an alternative approach for data analysis. Quality & Quantity, 49(2), 559–579. https://doi.org/10.1007/s11135-014-0009-8