Mental health and affective intolerance of uncertainty across domains: A unique role for intolerance of social uncertainty across the lifespan.

Humans' physical and social environments are filled with uncertainty.Negative reactivity to uncertainty has detrimental health impacts, especially for mental health.Higher levels of intolerance of uncertainty, defined as more negative responses to uncertainty, are associated with a greater risk of experiencing affective and anxiety disorders.Yet little is known about whether affective responses to uncertainty are the same across domains of uncertainty and whether they show cumulative or domain-specific associations with mental health.To address these knowledge gaps, the present study developed and validated a novel scale assessing affective responses to common types of uncertainty: academic/professional, climate, financial, health, political, and social domains of uncertainty in three independent samples (Sample A: N = 371, 18-76 years; Sample B: N = 403, 18-74 years; Sample C: N = 192, 18-32 years).All data were collected in 2025.The 24-item Affective Responses to Daily Uncertainty Scale offered a reliable measure of affective responses to uncertainty across domains.Negative affective responses across domains generally decreased with age.Social uncertainty demonstrated the strongest association with affective and anxiety disorder symptoms across age.Improving individuals' tolerance to social uncertainty therefore offers a promising target for intervention.