This review article examines the prevalence and correlates of adult attention-deficit hyperactivity disorder (ADHD) through a meta-analysis of 12 population-based studies. The pooled prevalence of adult ADHD was found to be 2.5% (95% CI 2.1–3.1). The study used meta-regression analysis to identify demographic correlates, finding that gender and mean age significantly influenced ADHD prevalence. The prevalence of ADHD decreased with age, particularly when men and women were equally represented in the sample. However, the authors note that the DSM-IV diagnostic criteria may lead to underestimation of ADHD prevalence due to potential biases in diagnosis. The study highlights that ADHD persists into adulthood in a significant proportion of cases, with a strong genetic component and structural and functional brain abnormalities. Adult ADHD is associated with various comorbid psychiatric disorders and socio-economic challenges. The study also notes that prevalence estimates can vary significantly depending on diagnostic criteria and study methodology. The authors emphasize the importance of using appropriate diagnostic criteria and considering methodological limitations when interpreting prevalence data. They also discuss the impact of sample selection and diagnostic tools on the accuracy of ADHD prevalence estimates. The study concludes that while the prevalence of ADHD declines with age, this may be due to underestimation of true prevalence, particularly in women, and the need for further research to understand the natural course of the disorder. The findings suggest that ADHD is a complex disorder with significant implications for adult health and well-being.This review article examines the prevalence and correlates of adult attention-deficit hyperactivity disorder (ADHD) through a meta-analysis of 12 population-based studies. The pooled prevalence of adult ADHD was found to be 2.5% (95% CI 2.1–3.1). The study used meta-regression analysis to identify demographic correlates, finding that gender and mean age significantly influenced ADHD prevalence. The prevalence of ADHD decreased with age, particularly when men and women were equally represented in the sample. However, the authors note that the DSM-IV diagnostic criteria may lead to underestimation of ADHD prevalence due to potential biases in diagnosis. The study highlights that ADHD persists into adulthood in a significant proportion of cases, with a strong genetic component and structural and functional brain abnormalities. Adult ADHD is associated with various comorbid psychiatric disorders and socio-economic challenges. The study also notes that prevalence estimates can vary significantly depending on diagnostic criteria and study methodology. The authors emphasize the importance of using appropriate diagnostic criteria and considering methodological limitations when interpreting prevalence data. They also discuss the impact of sample selection and diagnostic tools on the accuracy of ADHD prevalence estimates. The study concludes that while the prevalence of ADHD declines with age, this may be due to underestimation of true prevalence, particularly in women, and the need for further research to understand the natural course of the disorder. The findings suggest that ADHD is a complex disorder with significant implications for adult health and well-being.