Portuguese Version of the Arousal Predisposition Scale: Preliminary Evidence for a Two-Factor Structure in a Nonclinical Sample

Abstract

It is known that there is significant variability in arousal levels of the individuals. The Arousal Predisposition Scale (APS) is a questionnaire intended to measure individual differences in arousability. In the current work, our aim was to present the initial psychometric properties of the Portuguese version of the APS. Three hundred forty-five undergraduate medical students from both genders were enrolled. All participants filled out a set of questionnaires—which contained the APS—at the end of their lectures and out of the evaluation period. The APS showed good internal consistency (α = .85) and discriminated individuals with extreme scores. Further, in general, the scale discriminated as well both genders pertaining to the individual items and total score. In terms of scale structure, two related factors were extracted (F1 = emotional reactivity and F2 = trait anxiety). Significant associations among APS and other sleep and psychological self-report variables were also observed. The APS seems to be a reliable and valid instrument to assess self-reported physiological arousability, at least in a sample of young adults. The two-factor composition will require more studies to be replicated in similar groups and, particularly, in clinical samples.