Wildfires and mental health in adults and youth: Meta-analysis of prevalence estimates by assessment timing, diagnostic criteria, and assessment methods.

The increasing number of wildfires worldwide has drawn significant attention to their potential psychopathological consequences, primarily posttraumatic stress disorder (PTSD), depression, and anxiety. This meta-analysis aimed to quantify the prevalence rates of these disorders in wildfire-exposed adults and youth by quantitatively examining variations in prevalence estimates across measurement and methodological approaches, addressing a gap not previously explored in the literature. A systematic review was conducted following PRISMA guidelines. Several random-effects meta-analyses were conducted to estimate the overall pooled prevalence rates of each disorder. Subgroup analyses examined age group, assessment timing, diagnostic criteria, and assessment methods (self-report vs. clinician-administered). A total of 33 studies were included. Overall prevalence rates were 26.6%, 95% CI [19.7, 33.5] for PTSD; 28.9%, 95% CI [22.5, 35.2] for depression; and 25.2%, 95% CI [19.3, 31.1] for anxiety. Prevalence estimates for PTSD and depression significantly varied according to the time interval between wildfire exposure and assessment. Although PTSD prevalence estimates differed across assessment timing subgroups, depression followed a nonlinear pattern. Even several months after a wildfire, prevalence rates were higher than 14% for each disorder. Subgroup analyses showed no statistically significant differences according to age, diagnostic criteria, or assessment method. Overall, findings indicate that postwildfire prevalence estimates primarily reflect assessment timing rather than differences in age, diagnostic criteria, or assessment method. Clinically relevant levels of PTSD, depression, and anxiety persisted over time, highlighting the need for early intervention, sustained monitoring, and continued psychological support.