Confirmatory factor analysis applied to Matthews adjective checklist of self-reported activation: effect of time of day

Of the instruments devised for measuring self-reported activation, those that consider arousal dimensions (energy and tension) and a third dimension (hedonic tone, or pleasure/displeasure) allow a complete evaluation of the subjective mood. The inventory prepared by Matthews (1987a), which also incorporates a composite general arousal scale made up of items from the principal arousal scales, is one of the most frequently used. The present study assesses the consistency of the four scales of the inventory by means of a confirmatory factor analysis model and version VIII of the Lisrel computer package, and also its stability at different times of day (09:00, 13:00, 17:00 and 21:00). The study sample was made up of 671 healthy university students (236 men/435 women) aged between 17 and 38. Our results confirm the accuracity of fit/goodness of fit of the inventory's three principal factors. However, in our view, the secondary arousal factor should be defined or omitted, since its configura tion was poor at all times of day that the inventory was tested.