Background: This meta-analysis was designed to determine the relationship between reduction of attention-deficit/hyperactivity disorder (ADHD) symptoms and improvement in functioning by examining short-term changes in functional and symptomatic scores in children and adolescents with ADHD. Methods: Search of atomoxetine's clinical trial database identified four studies involving a symptomatic measure, the ADHD Rating Scale-IV-Parent Version:Investigator-administered and -scored (ADHDRS-IV-Parent:Inv), and a functional measure, the Life Participation Scale for ADHD (LPS). Results: Correlation analysis revealed a moderate-to-strong association between changes in the LPS total versus ADHDRS-IV-Parent:Inv total (r: -0.68). The LPS "Self-control" subscale showed higher correlations than the "Happy/Social" subscale with the symptomatic measures. Regression analysis also showed high sensitivity for functional measures to changes in symptom severity. Stratified analysis of mean changes in ADHDRS-IV-Parent:Inv scores corresponding to standardized changes in LPS functional scores indicated that a threshold reduction of 16-18 points on the ADHDRS-IV-Parent:Inv total score was needed for functional improvements to become evident. Conclusions: Subjects' symptomatic improvements appear to be reflected in improvements in their social and behavioral function as measured by the LPS. These initial findings warrant verification by replication with other outcome measures.