Initial psychometric characterization for the Portuguese version of the Morningness-Eveningness-Stability-Scale improved (MESSi)

ABSTRACT

This work reports the initial psychometric characterization of the Morningness-Eveningness-Stability-Scale improved (MESSi) for Portuguese young-adults (N = 466). A confirmatory factor analysis confirmed a three-factor model (i.e. Morning Affect, Eveningness and Distinctness) in our data, as originally proposed. Furthermore, construct validity evidence in relation to external variables (i.e. morningness/eveningness and satisfaction with life), as well as adequate reliability (i.e. internal consistency and test-retest reliability), were found. Finally, sex-based invariance and between-sex differences were investigated for the three subscales, as were correlations with age. Results point to the suitability of the MESSi for multi-cultural research on relevant and multiple aspects of chronotype.

KEYWORDS:

• MESSi
• distinctness
• morning affect
• eveningness
• psychometric characterization
• European Portuguese

Declaration of interest

The authors declare that they have no conflict of interest.

Notes

1. We should note that, in Portugal, there are a couple of other questionnaires to assess chronotype in adults, such as the MEQ (Silva et al. 2002) or the Composite Scale of Morningness (Martins et al. 1996).

2. A small percentage of the participants were not of Portuguese origin (specifically, 12.2% of the total sample and 9.9% of the test-retest subsample), but they were attending a Portuguese University and had been living in the country for several months.

3. Considering that higher scores on the MEQ refer to higher morningness, it would be expected that the correlations between scores on the MEQ and the external variable under consideration would be similar to those obtained with the Morning Affect measure of the MESSi. Concordantly, the scores on the MEQ correlated positively (though only marginally) with satisfaction with life (rs = 0.19, p = 0.06).

4. The same result was found when measuring Morningness using the MEQ within the current sample (i.e. z = −1.23, p = 0.22).

5. A similar pattern of results was found when the comparisons between males and females were based on similar-sized groups. To this end, a random subsample of the female participants (n = 126) was compared with the sample of the male participants (n = 124). No significant differences were found for Morning Affect (M = 14.47, DP = 4.24 and M = 14.89, DP = 4.43, for males and females, respectively; z = −0.87, p = 0.38, Cohen’s d = 0.097), and men scored significantly lower than women on Distinctness (M = 15.35, DP = 4.37 and M = 17.98, DP = 3.98, respectively; z = −4.86, p < 0.001, Cohen’s d = 0.63). Finally, males scored marginally significantly higher on Eveningness than females (M = 17.27, DP = 4.19 and M = 16.19, DP = 4.83, respectively; z = −1.89, p = 0.059, Cohen’s d = 0.24). Although the latter result just missed the conventional statistical level of significance, it should be noted that the effect size is similar to that obtained when comparing the full sample.

Additional information

Funding

The Portuguese Science Foundation provided partial support to Pedro F. S. Rodrigues (PhD Fellowship, ref. SFRH/BD/84279/2012) and to Josefa N. S. Pandeirada (Research and Investigator Grant, ref. IF/00058/2012/CP0172/CT0002). This article was also supported by the European Regional Development Fund through the operation POCI-01-0145-FEDER-007746 funded by the Programa Operacional Competitividade e Internacionalização – COMPETE2020 and by National Funds through FCT within CINTESIS, R&D Unit (Ref. UID/IC/4255/2013).