What are we measuring with the morningness-eveningness questionnaire? Exploratory factor analysis across four samples from two countries

Author(s)

Panjeh, Sareh ^[1] ; Pompeia, Sabine ^[2] ; Archer, Simon N. ^[3] ; Pedrazzoli, Mario ^[4] ; von Schantz, Malcolm ^[3] ; Cogo-Moreira, Hugo ^[1]

Affiliation

^[1] Univ Fed Sao Paulo, Dept Psiquiatria, Sao Paulo - Brazil

^[2] Univ Fed Sao Paulo, Dept Psicobiol, Sao Paulo - Brazil

^[3] Univ Surrey, Fac Hlth & Med Sci, Guildford GU2 7XH, Surrey - England

^[4] Univ Sao Paulo, Escola Arte Ciencias & Humanidades, Sao Paulo - Brazil

• Document type: Journal article
• Source: CHRONOBIOLOGY INTERNATIONAL; v. 38, n. 2, p. 234-247, FEB 1 2021.
• Web of Science Citations: 0

Abstract

Individual variability in diurnal preference or chronotype is commonly assessed with self-report scales such as the widely used morningness-eveningness questionnaire (MEQ). We sought to investigate the MEQ's internal consistency by applying exploratory factor analysis (EFA) to determine the number of underlying latent factors in four different adult samples, two each from the United Kingdom and Brazil (totalN= 3,457). We focused on factors that were apparent in all samples, irrespective of particular sociocultural diversity and geographical characteristics, so as to show a common core reproducible structure across samples. Results showed a three-factor solution with acceptable to good model fit indexes in all studied populations. Twelve of the 19 MEQ items in the three-correlated factor solution loaded onto the same factors across the four samples. This shows that the scale measures three distinguishable, yet correlated constructs: (1) items related to how people feel in the morning, which we termed efficiency of dissipation of sleep pressure (recovery process) (items 1, 3, 4, 5, 7, 9, 13, and 19); (2) items related to how people feel before sleep, which we called sensitivity to buildup of sleep pressure (items 2, 10, and 12); and (3) peak time of cognitive arousal (item 11). Although the third factor was not regarded as consistent since only one item was common among all samples, it might represent subjective amplitude. These results suggested that the latent constructs of the MEQ reflect dissociable homeostatic processes in addition to a less consistent propensity for cognitive arousal at different times of the day. By analyzing answers to MEQ items that compose these latent factors, it may be possible to extract further knowledge of factors that affect morningness-eveningness. (AU)

• FAPESP's process: 11/05804-5 - Phenotypic characterization of circadian rhythms in different genotype individuals for clock gene polymorphisms in different regions in Brazil: an emphasis on the effect of the gene PER3 and latitude
• Grantee: Mario Pedrazzoli Neto
• Support Opportunities: Regular Research Grants
• FAPESP's process: 13/17368-0 - Cardiovascular genomics: mechanisms & novel therapeutics - CVGen mech2ther
• Grantee: José Eduardo Krieger
• Support Opportunities: Research Projects - Thematic Grants