Dr. Stella Chess and her husband Dr. Alexander Thomas spearheaded the classic New York Longitudinal study in the early 1950s to track hundreds of children over a 30-year period to understand the tendencies that babies are born with and how they influence their lives, and from that research they developed the 9 Temperamental Traits.[i]

The traits are:

  1. Activity Level: how active is your child most of the time?
  2. Distractibility: how easily do outside influences distract your child?
  3. Intensity: how much intensity does your child have in her responses?
  4. Regularity: does your child vary in her eating or sleeping patterns?
  5. Sensory Threshold: how sensitive is your child to physical sensations?
  6. Approach/Withdrawal: how does your child respond to strangers?
  7. Adaptability: how easily does your child adapt to changes in his day?
  8. Persistence: how long will your child work to solve something that is hard?
  9. Mood: is your child a glass half empty or half full kind of person?


5 Chess, Dr. Stella, and Dr. Alexander Thomas. TEMPERAMENT: Theory and Practice. Psychology Press, 1996.

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