Notes: All figures are percentages. This table presents demographic composition and ADHD diagnosis rates for the nationwide Optum sample, the INPC sample, and comparisons to random sample of children from the 2019 National Health Interview Survey (NHIS). Each sample include children born between 2009 and 2014, not restricted to ADHD-naive subsamples. For comparison, the second column restricts sample to children covered by private insurance, whereas the fourth column includes all children, and all averages are weighted by the NHIS individual annual weights. For the NHIS samples, ADHD diagnosis rates are calculated as the percent of all children in the sample who report “current” ADHD diagnosis (either initially diagnosed in 2019 or continued diagnosis from the past). For Optum and INPC samples, we report analogous ADHD diagnosis rate as the percent of all children in sample who have an ADHD-related claim/encounter in 2019 (either initial diagnosis or treatment for continued diagnosis).