What kind of personality test should you use for leadership development?

The Five Factor Model of Personality

So this recent article in the NY Times created quite a stir on a professional listserv that I’m a member of (The Society for Consulting Psychology, a division of the American Psychological Association).

The gist of the article is that the author felt unjustly categorized by a personality test she took (the Myers Briggs Type Indicator, or MBTI) and wondered if it’s use contributes to a lack of diversity in the workplace.

The story piqued my interest because it mistakenly labelled the MBTI as a personality test, even though is has no psychometric validity. In other words, it doesn’t reliably and accurately measure personality. Despite this the test is incredibly popular and widely used in organizations across the world.

The continued branding of the MBTI as a personality test is interesting in light of recent attention it’s received in a book describing it’s dubious origins (The Personality Brokers).

I also got thinking about this topic because two different organizations just approached me about using MBTI or DISC (another personality type test that has similar limitations as MBTI) with their leadership teams at offsites this month, to promote team building.

Personality testing is a central feature of many individual- and team-based leadership development programs. For example I use personality testing whenever I conduct an assessment of an executive, and I often use these tools to support team-building activities with leadership teams. If you are an executive going through a leadership development process, or if you design these programs in your organization, you should know that there are two important categories of personality tests: selection-grade and non-selection grade.

Selection-grade tests have been rigorously built, tested and validated using multiple studies, to show that a) they can measure ‘something’ in a consistent way (e.g., over multiple time points), and b) that that ‘something’ is what the test company says it is (i.e., if they say they’re measuring extraversion, that they’re actually measuring extraversion). There are generally accepted scientific principles that guide the item-analysis and test validation process. Findings generated from completing those established steps must be available for viewing (albeit sometimes for a fee) in a technical manual. Another common attribute of selection-grade tests is that they are based in something called the Five Factor Model (FFM) of personality (this measures Openness to Experience, Conscientiousness, Extraversion, Agreeableness, and Neuroticism/Emotional Stability). Examples of selection grade tests are the Hogan Personality Inventory (HPI, popular in North America) and SHL’s Occupational Personality Questionnaire (OPQ, popular in the UK and Europe). Finally, they are called selection-grade because they have been so rigorously developed that they could be used in an employee selection situation, and withstand legal scrutiny.

Non-selection grade tests are all the other tests out there that purport to be personality tests, but which don’t make available their validation data/evidence, and which don’t follow the FFM. Examples of these tests are MBTI and DISC, but there are many others. Often (but not always) these tools provide a more simplified and accessible format for interpreting the results (e.g., they might associate certain traits with colours, which make the output easier to digest).

In my developmental executive assessments, I choose to use a FFM tool to supplement an interview-based 360 process. However, I know of very credible leadership development practitioners who use or have used the MBTI for development situations, and say it gives clients great value.

You might be wondering, why would anyone use a non-selection grade personality inventory? In development situations (where there is less legal risk at stake), there are actually a number of rational/credible reasons:

1. As I mentioned, sometimes the output is more accessible (I argued for the importance of this in a book review I wrote a couple of years ago). These tools may contain fewer dimensions to interpret — for example, a FFM tool may contain 5 broadly defined traits, and another 5 narrowly defined traits that comprise each broad trait. That totals 5x5=25 traits to interpret, which is a lot for someone who’s never looked at a personality test report before. By contrast, non-selection grade tests may cluster multiple FFM traits into a single bucket, in order to create fewer dimensions to interpret.
2. The results promote identification with the results. You may be a ‘Red’ (in DISC parlance), or an ENTP or INFJ (in MBTI language). These tools create profiles with clear labels associated with them. Having a clear label for your profile may make test takers accept the results more readily — “I am a RED! That’s me!” It sounds very clear and unambiguous. By contrast, FFM tools have more traits to interpret, more granularity, and the results don’t lend themselves to creating a clear and distinct profile. If I’m measured on 25 traits, and have percentiles associated with each, what’s my profile? There’s no clear answer.
3. The tests are easy to purchase. MBTI and DISC can be purchased and administered by anyone. You don’t have to take any certification training, and you don’t have to have any advanced psychology training. From a practical perspective, this just makes it easier for folks in organizations to access and use these tools. By contrast, selection-grade tests may require certification and/or a graduate degree in psychology to purchase and use.
4. Finally, the person providing feedback might be more experienced and confident using a non-selection grade tool. For example a consultant with a great deal of experience with the MBTI may be more confident that they can use that tool to unlock self-insight in the client, compared to a FFM tool. If the chance of having a high impact conversation is judged to be greater with MBTI (or DISC), based in part on the skill/experience of the facilitator, then it may be worth trading some of the inventory’s accuracy for that benefit.

My recommendation for any executive going through a leadership development process, is to use a FFM-based personality test.

However if you are going to use a non-selection grade test, here are some caveats that you should keep in mind:

1. Anyone can buy and/or use this type of tool regardless of psychological or statistical training.
2. These tests may not measure the dimensions (e.g., introversion, extraversion, etc.) that they claim to measure. They also may not measure those things consistently over time or across multiple administrations.
3. These tests are not used in research by world leading experts in the measurement of personality. Those researchers use FFM-based tests.
4. These tools can be used to spark self-insight, but not for decision-making. If you’re using the tool for selection or staffing, use a selection-grade tool. If you’re using the tool for development AND diagnostic purposes (e.g., for talent mapping, such that results may impact personnel decisions) use a selection-grade tool. If your purpose is just development, then you have more choice.

If you ever want to check the quality of a psyhometric test, you can go to Buros (https://buros.org) to view/purchase reports on test quality.

Finally if you want to take a free FFM test, here is a good site where you can do it (run by a researcher). You will receive a useful report summarizing your profile, and you can choose to take a long or short version.

Personality testing is an extremely valuable tool that can be used to support leadership development. I hope this post offers some insights in choosing the best tool for yourself and for your organization.

I would like to thank several members of the Society for Consulting Psychology whose input I benefited from in writing this post: Thor Levgold, Vicki Vandaveer, Michael Frisch, Allan Church, and Judith Walters.