Psychometric properties of the French version of the composite scale of morningness in adults.

The objective of this study was to provide a reliable instrument to measure morningness for upcoming studies in French samples, using the Composite Scale of Morningness (CSM), which has been translated into French. Nursing students (n = 356) completed the questionnaire between February and March 1997. The total score obtained was independent of age and gender, and normally distributed. The reliability was high (Cronbach's alpha = 0.85), and factorial analysis confirmed the unidimensionality of the scale. Evening-type subjects are thought to score under 31, and morning-type subjects are thought to score above 44. As an external validation, morningness was associated, on weekdays and weekends, with early rising times and bedtimes and early peak times of physical and mental performance. In conclusion, we found that the English and the French versions of the Composite Scale of Morningness gave identical results. The scale is reliable and can be used for French-speaking adult samples. Nevertheless, normative data and other external validity criteria are needed.