Table 5. Associations Between ADHD Medication Use and SweSAT Scores in Sensitivity Analyses^a.

Types of Cohort, Medication	No. of Patients	No. of Tests	Test Score Difference, Mean (95% CI)	P Value
ADHD diagnosed in the National Patient Register
Within patients only using stimulantsb	665	1816	3.81 (0.94 to 6.69)	.009
Within patients using nonstimulants or a combination of medicationsb	265	708	6.93 (1.81 to 12.05)	.008
Within patients without coexisting LD	844	2264	5.05 (2.47 to 7.62)	<.001
SSRI use and test scores
Not adjusted for ADHD medication	556	1475	2.71 (−0.57 to 5.99)	.11
Adjusted for ADHD medication	445	1207	2.37 (−0.88 to 5.63)	.15

Abbreviations: ADHD, attention-deficit/hyperactivity disorder; LD, learning disability; SSRI, selective serotonin reuptake inhibitor; SweSAT, Swedish Scholastic Aptitude Test.

^aEstimates of medication effect (ie, estimated mean difference in the test scores during medicated periods compared with nonmedicated periods) were from the within-patient analysis and adjusted for both linear and quadratic effects of age and the number of previous tests.

^bThe significance of the interaction of medication status and type of medication users was tested to indicate whether the mean test score differences during medicated vs nonmedicated periods were significantly different between patients only using stimulants and those using nonstimulants or a combination of medications (P = .23).