Toward a unified understanding of climate anxiety: Examining measures of climate and eco-anxiety

PLOS One | https://doi.org/10.1371/journal.pone.0339562 December 29, 2025 10 / 19 fit. To test this, we estimated a third model incorporating a higher-order factor—a second-level g-factor indicated by all four first-level factors from the four-factor model. This model met all fit thresholds for good fit. Given the high correlation between factors in the four-factor solution and the strong saturation of the higher-order factor (⍵ = .940), we concluded that the higher-order model was the most appropriate. It offers a more parsimonious structure while maintaining good model fit. Therefore, we recommend the use of the higher-order model for the Hogg Eco-Anxiety Scale. Joint model of climate and eco-anxiety. To examine the overlap between the Climate Anxiety Scale (CAS) and the Hogg Eco-Anxiety Scale (HEAS), we estimated joint measurement models incorporating all items from both scales. The first joint model combined the final measurement models of the CAS (g-factor) and the HEAS (higher order), allowing both general factors to correlate (M1). This model showed good fit (χ² (294) = 1294, p < .001, CFI = .965, TLI = .962, RMSEA = .038, SRMR = .027), with a high correlation between the two factors (r = .831). Given this strong Fig 2. Scheme plots of all tested models for the Hogg Eco-Anxiety Scale (HEAS). Note. HEAS-as = affective symptoms; HEAS-r = rumination; HEAS-bs = behavioral symptoms; HEAS-npi = anxiety about negative personal impact. https://doi.org/10.1371/journal.pone.0339562.g002