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DISC Validity and Adverse Impact

DISC Validity

Leading the field in DISC validity

Since 1984, TTI/Success Insights have always used outside, independent statisticians to validate all of their questionnaires including the DISC Assessment for robust DISC validity. Revalidation takes place every few years with the latest DISC validity study dated as 2011.  The intent is to provide a verifiable pattern of evidence that establishes the Style Insights instrument as a sound, reliable, valid, and usable instrument for a variety of purposes in personal and organizational development and for organizational and corporate use in a number of venues.

The research and statistics have been written and conducted to the specifications published in Standards for Educational and Psychological Testing (1999) cooperatively by the American Educational Research Association, American Psychological Association and the National Council on Measurement in Education. The guidelines provide the standards against which many US-based and international assessments are designed and validated. It is the purpose to respect those specifications and to encourage the reader to explore the standards in more detail. The reader is also encouraged to ask active questions about other assessments in the marketplace and to discover the extent to which those assessments followed similar guidelines to the Style Insights instrument and reports.


DISC Validity UK

Adverse Impact with DISC validity

  • Adverse Impact has been defined as “A substantially different rate of selection in employment decision that adversely affects a protected group based upon colour, religion, race, sex or national origin. It is a prima facie evidence of discrimation”.
  • Ensure that your chosen DISC system has been tested and accepted by the relevant authorities for DISC validity and Adverse Impact.  Ask to see (and keep) the Adverse Impact report to protect your organisation from legal proceedings. This is especially relevant when using assessments within the United States of America.

Contact Us to talk about TTI Success Insights® superior DISC validity and Adverse Impact or click here for further reading on TTI Success Insights® DISC validity


Modern development of Marston’s theory with DISC validity-Book launch

DISC Validity UK

Thousands of people daily take DISC (dominance, influence, steadiness, compliance) assessments. But, only a handful of people have read the text that started it all. Emotions of Normal People by William Moulton Marston was released more than 80 years ago and TTI Success Insights® is re-issuing the book that is the basis for all meaning and interpretation of the DISC theory.

Many have tried to release versions of Emotions in the past. But only TTI Success Insights® is providing a complete, un-abridged version, complete with a new foreword and epilogue that add insight and meaning to Marston’s seminal text.