DOES THE CHRONOTYPE CLASSIFICATION NEED TO BE UPDATED? PRELIMINARY FINDINGS

Abstract

Traditionally, chronotype classification is based on the Morningness-Eveningness Questionnaire (MEQ). It is implicit in the classification that intermediate individuals get intermediate scores to most of the MEQ questions. However, a small group of individuals has a different pattern of answers. In some questions, they answer as “morning-types” and in some others they answer as “evening-types,” resulting in an intermediate total score. “Evening-type” and “Morning-type” answers were set as A₁ and A₄, respectively. Intermediate answers were set as A₂ and A₃. The following algorithm was applied: Bimodality Index = (∑A₁ × ∑A₄)² − (∑A₂ × ∑A₃)². Neither-types that had positive bimodality scores were classified as bimodal. If our hypothesis is validated by objective data, an update of chronotype classification will be required. (Author correspondence: [email protected])

Keywords:

• Bimodal
• Chronotype
• Morning and evening oscillators

Declaration of Interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.