As a counter-anecdote, I have an early September birthday, but the 1st Sept cut-off was advisory rather than strictly enforced. So I was a “year ahead” of where

As a counter-anecdote, I have an early September birthday, but the 1st Sept cut-off was advisory rather than strictly enforced. So I was a “year ahead” of where I should have been for my exact age up until I was 13. At which point I repeated a year, going from the youngest of my classmates to the oldest. Exactly the sort of child the article implies would at risk of being over-diagnosed with ADHD as a pre-teen. Except I wasn’t diagnosed until almost 25 years later. Of course I’m just one data-point, but I’d be curious whether the developmental age differences might potentially _cause_ ADHD development among younger classmates rather than just indicate misdiagnosis.