This study followed 228 girls for 10 years. Of these, 140 had a careful childhood diagnosis of ADHD and 88 were matched comparison girls. The group was diverse in ethnicity and income. The girls were ages 6 to 12 when their executive function was tested (average 9.6 years). Nearly all took part again at ages 17 to 23 (216 of 228, or 95%).
Childhood executive function predicted several young adult outcomes. Errors when copying a complex figure predicted later math scores and being suspended or expelled. A working memory task, repeating digits backward, predicted later math and reading. When IQ was controlled instead of ADHD status, the reading link fell just short of significance.
Three childhood measures each predicted whether a young woman had a job: the figure task, missed targets on an attention test, and the digit task. But when the 42 participants under age 18 were left out, only the figure task still predicted employment.
ADHD status changed only two links. Working memory predicted reading, and the figure task predicted suspensions or expulsions, in the ADHD group but not the comparison group.
The links were small to medium. The sample was all female and mostly drawn from clinics. The tests were designed about 15 years earlier, and other factors cannot be ruled out.
The numbers Stats and what the terms mean
The statistics behind the plain-language claims above.
- Miller, 2011: reading link when IQ was controlled instead of ADHD status, p = 0.056.
- Miller, 2011: size of the links between childhood measures and young adult outcomes, correlations (r) of 0.1 to 0.3.
What the terms mean:
- p is the chance of seeing a gap at least this big if there were no real difference. Below .05 is usually read as unlikely to be chance alone.
- r is a correlation, from -1 to 1. 0 means no link, and values nearer -1 or 1 mean a stronger link.
Source: Miller M, Nevado-Montenegro A, Hinshaw S. Childhood Executive Function Continues to Predict Outcomes in Young Adult Females with and Without Childhood-Diagnosed ADHD. Journal of Abnormal Child Psychology (2011). doi:10.1007/s10802-011-9599-y