A Longitudinal Study of the Impact of COVID-19 on Optimism Prediction.

This article focuses on a longitudinal study investigating changes in optimistic predictions, hopelessness, and depressive symptoms before and after the COVID-19 pandemic, as well as their causal relationships. The study developed a future prediction task based on Item Response Theory (IRT) to measure optimistic predictions—defined as expecting positive events and not expecting negative events within the next month—and validated it using data from Japanese adults aged 20–79 collected in 2019 and 2021. Results showed a significant decline in optimistic predictions after the pandemic, driven by reduced expectations of positive events, while negative-event predictions remained stable; higher COVID-19-related stress was associated with lower optimism. Structural equation modeling revealed a circular causal relationship among low optimistic predictions, increased hopelessness (measured by the Beck Hopelessness Scale, BHS), and depressive symptoms (measured by the Beck Depression Inventory-second edition, BDI-II), with diminished optimism contributing to hopelessness. The study suggests fostering positive future expectations may help prevent hopelessness and depression, highlighting the future prediction task as a valid tool for assessing optimism in mental health research.