Researchers have discovered a disturbing link between over-diagnosis and the proliferation of standardized testing

“What the team found was that high rates of ADHD diagnoses correlated closely with state laws that penalize schools when students fail. Nationally, this approach to education was enacted into law in 2001 with No Child Left Behind, which makes funding contingent on the number of students who pass standardized tests. In more recent years, similar testing-based strategies have been championed by education reformers such as Michelle Rhee. But many states passed these accountability laws as early as the 1980s, and within a few years of passage, ADHD diagnoses started going up in those states, the authors found, especially for kids near the poverty line.”