Validation of Extended DISC®: Some interesting statistics


An ongoing validation process is an important function in the development process of any behavioural profile analysis or any psychological profiling method, although few developers publish their findings.

Extended DISC® International and FinxS systems are the exception and have recently produced their latest 2022 Validation Report as part of an ongoing and long-term validation process of the Extended DISC® Persona Management System, which, after several years of development, they released in 1994.  Importantly, the systems are continually enhanced, developed, and expanded.

This latest report is a continuation of previous two-yearly reports that summarise a continuing study of the Extended DISC® instrument and the four key dimensions which it assesses (Dominance, Influence, Steadiness and Compliance).  

The population was collected from the users of Extended DISC® and FinxS® Systems around the world and represents every age group, gender, organisation type and level in the same ratios that it is designed to be used. 

The total population used in the research was an impressive:

  • 1,237,505 for Behavioural Analysis,
  • 51,202 for the Sales Capacity Assessment,
  • 151,960 for Reasoning Analysis,
  • In a total of 86 languages for Behavioural Analysis.

Reliability and validity characteristics of the Extended DISC® Persona Management System are analysed by using various statistical methods. The results, methods and basic theory are also briefly discussed in the report and compared with related earlier reports. This report is based on data collected in both normal training and consultancy situations and during special data collection processes conducted by Extended DISC® International Ltd. and its associate consultants.

Would you like to know more? 

Contact Us

Reliability and Validity of Extended DISC® Behavioural Analysis

Internal consistency is a measure based on the correlations between different items on the same test (or the same subscale on a larger test). It measures whether several items that propose to measure the same general construct produce similar scores. It is usually measured with Cronbach’s alpha, a statistic calculated from the pairwise correlations between items. Internal consistency ranges between zero and one. A commonly accepted rule of thumb is that 0.6-0.7 indicates acceptable reliability, and 0.8 or higher indicates good reliability. High reliabilities (0.95 or higher) are not necessarily desirable, as this indicates that the items may be entirely redundant.

The global Cronbach’s alpha for the Extended DISC® Behavioural Analysis version 2022 (previous study) was:   

  • D = 0.81 (0.81)
  • I   = 0.79 (0.79)
  • S = 0.82 (0.82)
  • C = 0.78 (0.78)

The results prove that the instrument continues to have a very high validity.

Population statistics and interesting research findings

Behavioural Analysis is the most used Extended DISC® assessment because of its many applications and it is also the foundation of other assessments. Compared to other DISC based tools, Extended DISC® Behavioural Analysis goes more deeply into an individual’s personality, measuring something more unconscious, stable and natural than DISC tools have traditionally done.  Part of the reason for this, is that the process recognises and reports on 160 different styles, 40 in each quadrant, but for ease of comparison, given the large number of reports measured, the study has summarised these down into the four basic styles, choosing the major style in the reports to complete the analysis.  

Let’s take a look at some of the findings.

Global Distribution by Year

Global Distribution by Gender

These percentages have remained remarkably consistent over recent years with a trend in both genders towards an increase in ”S” styles and a decrease in ”D” styles.

Global Distribution by Generation

The stability of the instrument (proved by the very high correlation between the different years) supports the claim that the instrument has been able to maintain its reliability.


Global Distribution of 100% D, I, S and C Behaviours

The simplicity of many DISC systems has created a lack of credibility in the four quadrant model, but Extended DISC® ‘s identification of 40 styles within each quadrant provides a much deeper understanding of an individual’s behaviour.  The latest study shows that only a small percentage of global behavioural styles are 100% of one of the four styles.  The rest are a mixture of two or three styles.  In fact, only:

This is important to understand as oversimplification can provide misleading reports.

Book a FREE Consultation

Book a complimentary consultation with one of our team to discuss how Extended DISC® profiling can enhance your organisational performance.

Book Now

Invalid Profiles

Another method of monitoring the influence of the environment on the results is to follow the percentage of Invalid Profiles.  The Extended DISC® System has the strictest internal rules for identifying, and not processing, results that do not carry the required reliability.  Most, if not all, other DISC based programmes print every report, regardless of the consistency of the answers to their questionnaires.

The number of Invalid Profiles produced in a society is dependent on the assessment system processing, the environmental climate of the organisation and the stability of the society.

As a matter of comparison, Australian and New Zealand results are similar.  The percentages of Invalid Profiles are recorded for 34 countries in the Validation Report; below are some comparisons.

  • Australia
  • Brazil                        
  • China 
  • Finland                      
  • Germany 
  • India              
  • Korea                        
  • New  Zealand
  • Poland
  • Spain                         
  • United Kingdom
  • United States 

The report provides a comparison with the previous year and the results are similar to the 2022 percentages for each country.  The world average is 3.73%


National Stress Indicator™

The National Stress Indicator™ (NSI) is one outcome of Extended DISC® ’s continuous global research, and their interest in understanding not only individuals, teams, and corporations, but also whole nations.

In a behavioural sense, stress is the external pressure an individual feels that forces them away from their comfort zone.  A certain amount of stress comes with normal everyday tasks and responsibilities within a work environment.  The NSI does not measure stress that the individual has control over and accepts.

For this reason, the NSI measures the amount of negative stress pressure a group of individuals feels the environment is causing them.

Again, although the report has measured the NSI of 52 countries and detailed the stress recorded for the four main behaviours in each country, below are some simplified comparisons.


  National Male Female  
Australia 1.6 1.55 1.64
Brazil 1.24 1.22 1.27
China 1.7 1.68 1.75
Finland 1.7 1.65 1.76
Germany 1.58 1.56 1.63
India 1.41 1.39 1.48
Korea 1.81 1.79 1.82
New Zealand 1.57 1.52 1.63
Poland 2.19 2.37 2.21
Spain 1.53 1.52 1.55
United Kingdom 1.6 1.57 1.65
United States 1.59 1.58 1.63


The NSI gives society a lot to consider, and its purpose is to raise discussion within the country.  It clearly reflects not only the stress in the work environment but also the general attitude towards work and individualism.

Do you have questions?

Contact Us


Extended DISC® assessments are based on concepts of human behaviour accepted widely around the world, but they are not purely psychological tools.  They have a commercial focus and are used by management to increase the efficiency of an organisation.  They are utilised as part of daily management systems by thousands of organisations around the world.  They provide extremely important information about people involved in the organisation; information that would otherwise be much more expensive and time-consuming to obtain.

For a behavioural assessment to be considered reliable, it must provide dependable, repeatable, and consistent results over time.

Extended DISC® ’s focus on the continued collection of data and its regular comparison with previous statistics ensures that the users of Extended DISC® and FinxS® Systems know they have the most up to date and valid assessment instruments available.

As the study involves all countries using the systems and the comparison populations consist of randomly selected persons representing the normal target group of tools, it is a very compelling document. We are not aware of any similar study.

Anyone wishing to know more about the Validation Study or who requires samples of any of the multitude of Extended DISC® tailored reports available, should email or phone 1800 518 217 (Australia) or 0800 333 668 (New Zealand).  We know you will be impressed with the depth of the reporting.