Researchers compared 30 adults with ADHD (combined type) with 30 adults without ADHD. Each group had 14 women and 16 men. The groups were matched on IQ, education, income and gender. The 7 people who took stimulant medicine went without it for at least 24 hours before testing. The ADHD group scored higher on anxiety and low mood, and the analysis adjusted for this. Seventeen adults with ADHD who first qualified were excluded after testing.
Everyone did two computer tasks. The first was a slow, boring attention test that gave no feedback on mistakes. The second was a fast, game-like task that copied the work of a home-based accountant, with constant feedback on errors.
On the slow test, the ADHD group made more impulsive errors, meaning they responded when they should not have. This gap was unlikely to be down to chance. On the fast, work-like task, the two groups did about the same. They did not differ on impulsive errors, missed items, total time, planning or memory. The ADHD group did check the task's virtual clock more often than the control group.
The authors read this pattern as fitting best with the idea that boredom drives impulsive errors in adults with ADHD. They concluded that impulsiveness could be offset in a work-like setting. They said it is still unknown whether this holds in real workplaces, and that they could not tell which feature of the fast task helped.
The numbers Stats and what the terms mean
The statistics behind the plain-language claims above.
- Delisle, 2011: impulsive errors on the slow, boring test (T scores, adjusted for anxiety and low mood scores), ADHD 56 (13) versus controls 46 (10), F = 7.54, p = .008.
- Delisle, 2011: impulsive errors on the fast, work-like task, ADHD 14.4 (5.8) versus controls 13.2 (4.3), F = 0.47, p = .494.
- Delisle, 2011: missed items on the fast, work-like task, 9.5 (4.3) versus 10.0 (3.1), p = .873.
- Delisle, 2011: total time on the fast, work-like task, 55.6 (11.1) versus 54.8 (12.6) minutes, p = .727.
- Delisle, 2011: whether the gap in impulsive errors differed between the two tasks, F(1, 58)= 5.63, p = .021.
- Delisle, 2011: checks of the virtual clock on the fast task, ADHD M = 21.2, SD = 11.8 versus controls M = 15.2, SD = 10.4, t = 2.1, p = .042.
What the terms mean:
- p A number from a statistical test that shows how unusual a result would be if there were really no group difference. It depends on the study's own assumptions being right.
- F and t Test results used to work out the p-value; a bigger number means a bigger gap compared with the spread in scores.
- M and SD M is the average. SD (and the number in brackets after each score) shows how spread out the scores were.
- T score A score scaled so that the typical person scores 50.
- Control group The group in a study that doesn't get the thing being tested, so the other group has something to be compared with. Here it was the 30 adults without ADHD.
Source: Delisle J, Braun C. A Context for Normalizing Impulsiveness at Work for Adults with Attention Deficit/Hyperactivity Disorder (Combined Type). Archives of Clinical Neuropsychology (2011). doi:10.1093/arclin/acr043