Myers-Briggs, DISC, StrengthsFinder and the Core Values Index Psychometric Assessments

In this article, we compare four of the top psychometric assessments on the market today, Myers-Briggs Type Indicator (MBTI), the DISC, StrengthsFinder, and the Core Values Index.

Reliability and Validity

Reliability and validity are the two keystone ways to measure the value and quality of a psychometric assessment. Test-retest consistency is the standard for reliability, and is fairly straightforward to understand. How similar are results from one assessment to another? A 100% reliability rating would indicate results are exactly the same between different assessments for a given individual over time.

Validity is a bit more difficult to measure. Validity refers to the accuracy of the assessment to measure the psychometric traits of the individual. It can also measure the ability of the assessment to predict the performance or behavior of the individual, such as in a new job or career track.

The value of a psychometric assessment can also be viewed by how easily the results can be deliberately or unintentionally skewed by the individual.

Skew

The way a psychometric assessment functions has a big impact on its validity. There are two types of assessment methodologies, question types and cue types.

Assessments that use phrased questions, such as asking the individual to rate how much they agree or disagree with the statement, "I am a natural-born leader," can easily be skewed because the intent of the question is clear.

Cue-type assessments use other feedback mechanisms that hide the intent or meaning behind the available options.

Essentially any psychometric assessment that uses phrased questions or discernible context can be skewed, thus reducing their reliability and validity. Only the Core Values Index of the four assessments we reviewed uses the cue-type mechanism — simple word choices. Results are nearly impossible to skew.

Myers-Briggs Type Indicator

• Reliability: 5/10
• Validity: 2/10
• Cost: $50
• Time: 45 minutes

The MBTI is a test that aims to identify where an individual falls on four different dichotomies—sensing or intuition, introversion or extroversion, thinking or feeling, and judging or perceiving—and comes up with 16 different personality types labelled by combinations of initials.

MBTI is based on eight hypothetical assumptions and until this day there has been no scientific proof to support the claims of the method.

Source: https://www.linkedin.com/pulse/mbti-serious-test-why-robbrecht-van-amerongen

Reliability

According to Myers-Briggs' own literature, their Type Indicator assessment has an overall repeat reliability ranging between 75% and 90%. However, many studies and anecdotal reports indicate the actual repeat reliability rating of the MBTI would struggle to reach 70%.

Validity

The Myers-Briggs Type Indicator was originally created by two individuals in the early 1900s that had no formal education or training in psychology. It was inspired by the work of Carl Jung, who admitted the basis of his research was anecdotal and has not been subjected to any control study.

Furthermore, despite the fact that it is estimated more than 75% of Fortune 500 companies use psychometric testing in recruitment:

There is no evidence to show a positive relation between MBTI type and success within an occupation.

Many traditional assessments [other than the Core Values Index] have been debunked by psychologists, such as the infamous Myers-Briggs Type Indicator.

Source: https://www.forbes.com/sites/forbestechcouncil/2019/07/19/is-hr-ready-for-the-new-age-of-psychometrics-testing/

For these reasons, we rate the validity of the MBTI at just 2 out of a possible 10 points.

Time and Cost

The MBTI takes about 45 minutes to complete and costs $50.

DISC

• Reliability: 4/10
• Validity: 4/10
• Cost: $29
• Time: 20 minutes

DISC is another personality assessment tool that is gaining fast popularity amongst the human resource professionals. DISC as a behavior assessment tool was developed by industrial psychologist Walter Vernon Clarke and is based on the theory of psychologist William Moulton Marston.

As an assessment tool it focuses on identifying four different behavioral traits: dominance, inducement, submission and compliance. Based on these behavior traits, the individuals may be categorized as either task-oriented or people-oriented.

Reliability and Validity

In the case of DISC assessments, the repeat reliability and validity of the results are both in question because the meaning behind the possible answers are obvious. The individual taking the assessment can choose to answer the questions honestly and without intent to skew the outcome, but their answers would still be subject to their mood and mindset at the time.

Time and Cost

The DISC assessment takes about 20 minutes to complete and costs $29.

StrengthsFinder / CliftonStrengths 34 Assessment

• Reliability: 4/10
• Validity: 4/10
• Cost: $50
• Time: 45+ minutes

Created by Donald Clifton, a former chairman of Gallup (the polling company), StrengthsFinder is a combination of a self-help book written by Marcus Buckingham and Donald O. Clifton, first published in 2001, and an online personal assessment test that attempts to outline the user's strengths.

Reliability and Validity

StrengthsFinder, now called CliftonStrengths 34, asks the user 177 questions and takes about 35-45 minutes to complete. The associated book takes much longer to read. Because the questions reveal the nature of what is being assessed, it is very easy for the individual to skew their results toward a desired outcome.

It is perhaps most telling when we review what one person commented on Quora.com about the validity and reliability of StrengthsFinder:

"Some people don't resonate with their [StrengthsFinder] results, which makes me wonder if ... those people aren't good at assessing personality (including their own)."

This implies that the person taking the assessment is somehow responsible for its results through deliberate will. Conversely, if an assessment is reliable and valid, it shouldn't be possible for the individual to influence the results.

See: Reliability and Consistency in Psychometrics

Time and Cost

The CliftonStrengths assessment itself takes about 45 minutes to complete, and the associated book takes much longer to read. The book and online assessment cost $50.

Core Values Index (CVI)

• Reliability: 10/10
• Validity: 9/10
• Cost: $50
• Time: 10 minutes

The Core Values Index is the newest psychometric assessment of the four reviewed here, created in the early 1990's by Lynn Ellsworth Taylor. Unlike the MBTI, DISC, and CliftonStrengths assessments, the CVI is cue-based rather than asking proper questions. This prevents the individual from gleaning the intent of the available choices and skewing their assessment toward a desired result.

Reliability

Of the four assessments reviewed, the CVI has the highest repeat reliability. Longitudinal studies have confirmed the CVI has a 97.7% average repeat reliability rating, the highest of any psychometric assessment on the market today.

Validity

The predictive validity of the Core Values Index psychometric assessment is unmatched. The CVI is often used as part of the pre-hiring screening process. The characteristics of the role are analyzed into a set of scores. Candidate CVI scores are compared against the role to determine a predictive level of fit. Individuals with highly matched profiles to a role often have 200% or higher productivity than their unmatched peers, and 50% or lower turn-over.

The Core Values Index presents the user with several sets of words in groups of four. They are asked to choose two of the four that resonate with them the most. This makes it nearly impossible to intentionally or unintentionally skew the assessment toward a particular result because the connection between the available words and their resultant outcome is indeterminable.

Time and Cost

The CVI takes 8-10 minutes to complete and costs $49.95.