Convergent, Discriminant, and Incremental Validity of the Nightmare Proneness Scale

The Nightmare Proneness Scale (NPS) shows promise as a measure of a personality trait that makes people more likely to have frequent nightmares. In a sample of 140 university students, the scale's scores correlated with nightmare frequency, distress from nightmares, effects of nightmares, general psychological distress, neuroticism, and trauma symptoms, supporting its convergent validity. Discriminant validity was shown by weak or absent correlations with feminine gender role, habitual sleep length, and social desirability. The NPS also predicted additional variance in nightmares beyond that explained by general distress, neuroticism, and trauma symptoms combined, as well as beyond nightmare distress and effects.

Study at a glance

Abstract

The current study examined the validity of the Nightmare Proneness Scale (NPS; Kelly, 2018) as measuring a personality disposition that predisposes individuals to experience frequent nightmares. The NPS and measures to estimate its convergent and discriminant validity were administered to a sample of 140 university students. The convergent validity of the scale was supported through significant correlations with nightmare frequency, nightmare distress, nightmare effects, general psychological distress, neuroticism, and trauma symptoms. Discriminant validity was demonstrated through nonsignificant correlations with feminine gender role, habitual sleep length, and social desirability. Regression results indicated that the NPS significantly predicted incremental variance in nightmares above general distress, neuroticism, and trauma symptoms combined as well as above nightmare distress and nightmare effects. The results and suggestions for additional research on the NPS and nightmare proneness were suggested.