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Updated: May 12, 2026

Human Circadian Phenotyping and Diurnal Performance Testing in the Real World
10:16

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Published on: April 7, 2020

A Journey Through Chronotype Changes in University Students.

Esther D Domenie1,2, Davide Erminelli1, Gianluca Giusti1,3

  • 1Department of Medicine, University of Padova, Padova, Italy.

Journal of Biological Rhythms
|May 11, 2026
PubMed
Summary

Chronotype shows relative stability in young adults but can shift, especially with behavioral advice. About 30% of students changed their self-assessed chronotype category over time.

Keywords:
assessmentchronotypemidsleepsocial jetlagstudents

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Area of Science:

  • Chronobiology
  • Sleep Science
  • Behavioral Science

Background:

  • Chronotype, an individual's preferred sleep-wake timing, is generally considered stable but can fluctuate.
  • University students experience unique academic year constraints impacting sleep patterns.
  • Circadian hygiene education aims to improve sleep timing and consistency.

Purpose of the Study:

  • To investigate the temporal stability of self-assessed chronotype in university students.
  • To examine how behavioral advice on sleep, meal, and exercise timing affects chronotype.
  • To analyze changes in chronotype measures like midsleep and social jetlag over time.

Main Methods:

  • A large cohort of university students participated in a 2-arm circadian hygiene education initiative.
  • Chronotype was assessed using the Self-Morningness/Eveningness (Self-ME) question and the Ultrashort Munich ChronoType Questionnaire (μMCTQ).
  • Repeated assessments were conducted over 2-22 months, with sample sizes ranging from 1902 to 2820 participants.

Main Results:

  • Good agreement was found between subsequent Self-ME assessments (Cohen's k between 0.6-0.8), with ~70% confirming their initial category at 2 months.
  • Approximately 30% of participants changed chronotype categories, with those who moved once being more likely to move again.
  • Midsleep and social jetlag showed yearly variations, and circadian hygiene interventions had slight, differential effects on chronotype stability.

Conclusions:

  • Chronotype in young adults is relatively stable but exhibits plasticity within certain limits.
  • Chronotype stability is influenced by measurement methods and behavioral interventions.
  • The academic year's structure impacts student sleep timing, affecting chronotype measures.