Do ‘Sleepy’ and ‘Tired’ Go Together? Rasch Analysis of the Relationships between Sleepiness, Fatigue and Nonrestorative Sleep Complaints in a Nonclinical Population Sample

Abstract

NRS complaints can simultaneously present with higher daytime fatigue and sleepiness levels but the associative relationships between fatigue and sleepiness remain relatively unaffected by NRS. Although participants might not present adequate differentiation, fatigue and sleepiness seem to relate to different underlying concepts.