The Chinese Morningness-Eveningness-Stability-Scale improved (MESSi): validity, reliability, and associations with sleep quality, personality, affect and life satisfaction.

Individual differences in time of day preference have important correlates. Morningness is associated with greater well-being, while eveningness is associated with more maladaptive behaviors, psychological distress, and disorder. The availability of valid, reliable, questionnaire scales is central to this ongoing research. The recently developed Morningness-Eveningness-Stability-Scale improved (MESSi) utilizes items from previously established scales to assess the dimensions of Morning Affect (MA), Eveningness (EV), and amplitude of diurnal variation/distinctness (DI). The current study developed a Chinese version of the MESSi scale. A sample of 767 Chinese university students completed the translated MESSi, the reduced Morningness-Eveningness Questionnaire (rMEQ), and scales assessing sleep quality, positive and negative affect, the big five personality dimensions, and life satisfaction. An independent sample of 80 undergraduates completed the MESSi twice over a 14-19 day period. Exploratory and confirmatory factor analysis both supported the original three-factor structure of the MESSi, with the subscales of MA, EV, and DI. Internal consistency and test-retest reliability were acceptable/good, and expected correlations with other measures were found, including: MA correlated positively with the rMEQ, conscientiousness, positive affect, and life satisfaction; EV correlated negatively with rMEQ and conscientiousness; DI correlated positively with poor sleep quality, negative affect, and neuroticism. Overall, the results support the validity and reliability of the Chinese version of the MESSi.