A Fair Map: Big Five, MBTI, DiSC and the Enneagram
Where you are: Module 1 · Lesson 2 of 30 · about 22 minutes (reading 12, practice 10). Lesson 1 said the evidence for the Enneagram is mixed. This lesson compares it fairly with three frameworks you may meet at work, without ranking any of them.
What you'll be able to do
- Say what each of four frameworks is for, in its owner's or authors' words.
- Tell an owner statement from an independent finding, and reliability from accuracy.
- Mark a claim as supported, overstated or not claimed by the sources this course used.
- Explain why this course uses the Enneagram without claiming it is the best.
Two kinds of source
When someone says "this framework is accurate", first ask who said it.
- An owner is the person or company that publishes a framework or its test. Owners can describe their own framework well, but most of them also sell it, and the figures they publish are their own.
- Independent research is done by people who do not sell the framework.
Both are worth reading. They are different kinds of evidence, so this lesson always says which one it is reporting.
Reliability is not accuracy
A test is reliable when it gives similar results each time. It is valid (accurate) when its results mean what it claims they mean. A bathroom scale that always shows two kilograms too much is reliable but not accurate. Owners often publish reliability figures. A high reliability figure does not show that a framework is accurate.
More words you will meet:
- A meta-analysis combines the results of many earlier studies into one result. A systematic review collects and compares many earlier studies.
- Test-retest means the same people take the test twice, to see whether the results match.
- Internal consistency means the questions in one scale give answers that agree with each other.
- A reliability coefficient is a number from 0 to 1; higher means more consistent.
- Conscientiousness means being careful, organised and dependable.
- A link (correlation) of .19 is low, on a scale from 0 (no link) to 1 (a perfect link).
The fair map
| Framework | What it describes | What its owner or authors say | What the independent work used here says |
|---|---|---|---|
| Big Five | Five broad dimensions of personality, each measured by degree, not as a type. The public item pool, IPIP, offers questionnaire scales for them. | The IPIP page prints reliability figures of about .8 to .9 for its scales (owner figures). The items are free to use. | A 1991 meta-analysis found conscientiousness was the one trait with consistent links to job performance across all five occupational groups, and extraversion also predicted performance for managers and sales. A 2021 synthesis of more than 50 meta-analyses gives conscientiousness the strongest link to overall performance (about .19), with the other traits weaker (about .10 to .13). |
| MBTI | Four preferences that combine into a type | The publisher reports internal consistency of about .90 and test-retest above .80 over up to 15 weeks, and says about 50 percent of people get the same four-letter type on retest (owner figures). It says the MBTI measures preferences, not competence, and is not for hiring or team placement. | Two reviews disagree. A 2017 review judged reliability satisfactory on three scales and warned that the evidence is mostly from college-age samples. A 2025 article reported inconsistent test-retest results, with about half of respondents getting a different type on retest. |
| Everything DiSC | Four styles. The owner says everyone is a blend of all four, and no style is better or worse. | The publisher's research report gives a median reliability of .87 and a median two-week test-retest of .86 (owner figures). | This course used no independent study of DiSC, and did not search for one in depth. |
| Enneagram | Nine patterns of attention and motive (our wording), with a path of growth, as Chestnut and Paes teach it | Chestnut and Paes describe it as the basis of "a highly accurate typology" (an author claim). In 1996, Riso wrote that there was, "at present", no scientific proof for the nine types. | A 2021 systematic review of 104 samples found mixed evidence of reliability and validity. A 2018 study of people who chose intensive Enneagram trainings found gains in one measure in some participants, but its design cannot show the training caused them. No source measured manager results. |
What the table does not say
- It does not rank the frameworks. None of the sources compares their accuracy head to head.
- "This course used no independent study" describes what was read. It does not claim that none exists.
- It says nothing about studies this course did not read.
Why this course uses the Enneagram
The reason is fit for a purpose, and the choice is this course's. The course is self-paced, with no coach beside you. So it needed a map that links four steps you can take alone: notice a reaction, ask what it might be protecting, make a choice, and try a small experiment. That chain is this course's own design, built on the authors' idea that a pattern of attention links to a motive.
The Big Five, the MBTI and DiSC were built mainly to describe traits, preferences or style, and each may be useful for other purposes. This course does not say its choice is more accurate or more scientific.
Where any of them goes wrong at work: when it is used to label a person and then to decide something about them. The MBTI publisher itself says not to use its tool for hiring or team placement. The same caution applies to every framework in this course.
Three questions for any framework claim
- Who is saying this?
- Is it an owner statement or independent research?
- What exactly was measured: consistency, accuracy or something else?
These three questions will help you with the next framework a vendor shows you.
Worked example
Claim: "The MBTI publisher reports test-retest reliability above .80, so the MBTI is accurate."
- Who says it? The publisher. It is an owner figure.
- What does the figure measure? Consistency over time, not accuracy.
- Independent evidence? The two reviews in the table disagree about reliability. Neither shows that a reliability figure proves accuracy.
So the claim is overstated. A supported version is: "The MBTI publisher reports test-retest above .80 over up to 15 weeks (an owner figure); independent reviews disagree."
Your turn
Work privately in your own notes.
Part 1. Match the purpose. Match each statement to the Big Five, the MBTI, Everything DiSC or the Enneagram as this course uses it.
- "Four styles; everyone is a blend of all four, and no style is better."
- "Five broad dimensions, each measured by degree."
- "Nine patterns of attention and motive, used here for private reflection."
- "Four preferences that combine into a type."
Part 2. Mark the claim. Mark each one: owner statement, independent finding, overstated or not claimed by the sources used. Name the source.
- "The Myers-Briggs Company says the MBTI is not meant for hiring or team placement."
- "Wiley reports a median reliability of .87 for Everything DiSC."
- "Independent research shows Everything DiSC is more accurate than the Big Five."
- "The Enneagram has been proven valid."
Part 3. Write one fair-comparison paragraph (three or four sentences): what the four frameworks are for, what kind of evidence stands behind the Enneagram, and why this course uses it, with no ranking.
Check your work
Part 1. 1 DiSC; 2 Big Five; 3 Enneagram; 4 MBTI.
Part 2.
- 5: owner statement (the publisher). It is the owner speaking about its own product, which is fair to report as the owner's.
- 6: owner statement, not independent (Wiley's research report). It reports reliability, not accuracy.
- 7: not claimed by the sources used. No independent DiSC study was used, and no source compares DiSC with the Big Five.
- 8: overstated. The 2021 review found mixed evidence, and in 1996 Riso wrote that there was no scientific proof.
Part 3, one good paragraph. "The Big Five describes five traits by degree, the MBTI four preferences, and DiSC four styles; the Enneagram, as Chestnut and Paes teach it, describes nine patterns of attention and motive. The figures for the MBTI and DiSC come mostly from their owners, and independent reviews of the MBTI disagree. For the Enneagram, a 2021 review found mixed evidence, so it is author teaching, not a validated test. This course uses it because it links noticing a reaction to a question about motive and a small experiment, not because it is more accurate."
Criteria: each claim attributed to the right owner or author; owner figures never treated as independent; evidence scoped to the sources used; no ranking and no claim of proof. A mark of "overstated, because no independent DiSC study was used" for item 7 is also acceptable.
Extra practice (optional)
Mark each statement in the same way.
- "One review judged MBTI reliability satisfactory on three scales, with mostly college-age samples."
- "The Big Five is the only framework with independent evidence."
- "Wiley reports a two-week test-retest of .86 for Everything DiSC, so DiSC measures people accurately."
- "Everything DiSC is used in more workplaces than the Big Five."
Key. 1: independent finding (the 2017 MBTI review). 2: overstated; the table shows independent work on the MBTI and the Enneagram too. 3: overstated; .86 is the owner's consistency figure, not proof of accuracy. 4: not claimed; nothing in the table counts workplaces.
Knowledge check
A salesperson says: 'Our test is accurate, because our own report shows a reliability of .87.' What is the best response?
Which sentence follows this course's approach?
What does 'this course used no independent study of DiSC' mean?
Answers explained
- C separates consistency from accuracy and notes the figure is the seller's. A confuses the two ideas. B is too strong: owner reports are fair sources for what the owner says. D treats a number as proof.
- A is the course's own reason and claims no accuracy. B, C and D each claim a ranking or scientific advantage that no source supports.
- D describes only what was read. A claims something about all research. B and C draw conclusions from a gap in reading.
Key takeaways
- Ask who is saying it. Owner figures describe the owner's product; independent research is a different kind of source.
- Reliability is consistency. It is not accuracy.
- Mark a claim as supported, overstated or not claimed by the sources you have used.
- This course uses the Enneagram for one purpose, reflection on your own reactions, and claims it is neither the most accurate nor the most scientific.
Sources
- The Myers-Briggs Company. "MBTI facts." themyersbriggs.com (owner page; owner figures and the statement on hiring and team placement; seen as a search extract).
- John Wiley and Sons. Everything DiSC research report, revised 17 November 2020. everythingdisc.com research report (owner report; extracts of the reliability and validity sections). Wiley's "Navigating the DiSC Model" page, everythingdisc.com (search extracts only: four styles, everyone is a blend, no style better or worse).
- International Personality Item Pool. "Big-Five Factor Markers." ipip.ori.org (owner page; five factors and printed reliability figures).
- Zell and colleagues (2021) "Big Five personality traits and performance: a quantitative synthesis of 50+ meta-analyses." Journal of Personality 90(4). doi.org/10.1111/jopy.12683 (abstract only).
- Barrick, M. R. and Mount, M. K. (1991) "The Big Five personality dimensions and job performance: a meta-analysis." Personnel Psychology 44(1). doi.org/10.1111/j.1744-6570.1991.tb00688.x (abstract only).
- Randall, K., Isaacson, M. and Ciro, C. (2017) "Validity and reliability of the Myers-Briggs Personality Type Indicator: a systematic review and meta-analysis." Journal of Best Practices in Health Professions Diversity 10(1), 1 to 27 (abstract and first page only; no DOI found).
- Rajeswari and colleagues (2025) "Investigating the psychometric properties of the Myers-Briggs Type Indicator." International Journal of Social Science Research 2(3), 201 to 209. doi.org/10.70558/ijssr.2025.v2.i3.30388 (abstract only; the journal's rigour was not judged).
- Hook, Hall, Davis, Van Tongeren and Conner (2021) "The Enneagram: A systematic review of the literature and directions for future research." Journal of Clinical Psychology 77(4). doi.org/10.1002/jclp.23097 (abstract only).
- Daniels, Saracino, Fraley, Christian and Pardo (2018) "Advancing Ego Development in Adulthood Through Study of the Enneagram System of Personality." Journal of Adult Development 25, 229 to 241. doi.org/10.1007/s10804-018-9289-x (read in full; the measure was ego development; the main comparison between groups was not statistically significant).
- Chestnut, B. and Paes, U. (2021) The Enneagram Guide to Waking Up. Hampton Roads Publishing ("a highly accurate typology").
- Riso, D. R. with Hudson, R. (1996) Personality Types, revised edition. Houghton Mifflin. The history section, PDF page 42 ("no scientific proof").
- The reason this course uses the Enneagram, the four-step chain and the three questions are the course designers' own, not a research finding.