Does impression management impact the relationship between morningness–eveningness and self-rated sleepiness?

We examined the psychometric properties and construct validity for the Morning Affect (MA) scale; this scale is a subset of the morningness factor from the Composite Scale of Morningness (CSM). We also addressed some problems with this literature. First, we employed an older working sample that was not gender biased. Second, we argued whether self-reported dependent variables that are used to assess construct validity may be biased by impression management; an intentional attempt to be perceived favourably. The psychometric properties of the MA were comparable to the CSM. Confirmatory factor analysis supported the four-item posited model structure of the MA scale. As expected morning types were more alert during the early hours of the day and evening types toward the latter period of the day (p < .001). Participants that scored high on impression management also rated themselves to be significantly more alert during the morning hours only (p < .05). No interaction was observed between morningness–eveningness and impression management suggesting that the self-reported sleepiness ratings were an appropriate indicator to demonstrate construct validity.

► Structural equation modelling confirmed the factor structure of the Morning Affect scale. ► The psychometric properties of the Morning Affect scale were strong. ► Construct validity was demonstrated against self-rated sleepiness by time of day. ► Self-reported sleepiness ratings were not distorted by impression management.