“…It is difficult to explain this discrepancy. There are several possible explanations: inadequate clinical education on comorbid psychiatric assessment in older adults (Goodman, 2009;Goodman & Thase, 2009;Weisler & Goodman, 2008), medical illnesses in older adults may consume clinicians' time not allowing for comprehensive psychiatric assessment (Adelman et al, 2000;Herndon et al, 1997), assumption that the likelihood of undetected mental health disorders is negatively correlated with duration/age (Buitelaar & Ferdinand, 2013;Chen et al, 2018;Soegaard, 2012), and ageism bias dismissing psychiatry symptoms in older adults (Asherson et al, 2012;Officer et al, 2016;Ribeiro-Goncalves et al, 2023;Temple et al, 2021). Previous studies also indicate that impairments related to ADHD (e.g., financial issues, unemployment, and social structure) can change with age (Anker et al, 2017;Brown et al, 2017;Holst & Thorell, 2020;L et al, 2022;Lensing et al, 2015;Michielsen et al, 2015), which could be related to our findings in that younger patients and older patients had different levels of documented impairment related to their ADHD.…”