A Psychometric Evaluation and Validation of the Preferences Scale

Abstract

The Preferences Scale (PS) is a new measure of morningness and therefore requires intensive investigation to establish its measurement properties and validity. A confirmatory factor analysis (CFA) of Smith and colleagues (2002) posited model structure was not optimal in both a student (n=731) and working sample (n=218). However, significant differences (p<0.01) were found for times to sleep and wake between morning and evening types. Principal components and reliability analyses were used to develop a 6‐item model comprising 2 factors using a student sample (n=368). Cronbach's α for the PS was 0.73 and the factors explained 61% of the variance. The revised model was replicated via CFA in a separate student sample (n=363). A subsequent CFA confirmed the model structure in the working sample. Cronbach's α was 0.74 and the factors explained 64% of the variance. Significant differences (p<0.01) in self‐reported alertness ratings between morning and evening types were obtained by time‐of‐day. These results provide preliminary support for the PS. The predictive efficacy of the PS requires further validation against a number of health and work‐related variables.

• Alertness
• Circadian
• Preferences
• Morningness
• Eveningness