Reconsidering the construct validity of self-reported chronic stress: A multidimensional item response theory approach.

Emerging evidence shows that the construct validity of commonly used chronic stress measures is questionable. Item response theory was used to evaluate the psychometric properties of the Perceived Stress Questionnaire (PSQ), the Perceived Stress Scale (PSS), and the Screening Scale of Chronic Stress (SSCS). Using multidimensional item response modeling of data from two population-based samples (N₁ = 5,379, N₂ = 504), we identified and conceptually replicated a five-dimensional model combining items of chronic stress, neuroticism (i.e., Big Five Inventory Neuroticism scale; BFI-N), and depressiveness (i.e., Patient Health Questionnaire depressiveness scale; PHQ-9). The findings suggested a major overlap of variance between items of the applied instruments forming a pronounced common latent scale, which appeared to be mainly based on the perceived extent of freely available energy (i.e., vitality vs. fatigue). Accordingly, the overlap between items of the PSQ, PSS, and SSCS was larger with PHQ-9 items than BFI-N items. Specifically, items of chronic stress seem to discriminate subclinical manifestations of fatigue, a core symptom of depressiveness. Subsequently estimated person parameters were used to predict hair cortisol concentrations (HCC), a physiological indicator of chronic stress. Controlling for potential confounders, only the common latent scale showed a weak association with HCC, whereas residual variance components were not predictive of HCC. This finding further supports the notion that instruments like PSQ, PSS, and SSCS show an impaired construct validity. (PsycInfo Database Record (c) 2020 APA, all rights reserved).