Young adult outcomes in the follow-up of the multimodal treatment study of attention-deficit/hyperactivity disorder: symptom persistence, source discrepancy, and height suppression.

BACKGROUND: The Multimodal Treatment Study (MTA) began as a 14-month randomized clinical trial of behavioral and pharmacological treatments of 579 children (7-10 years of age) diagnosed with attention-deficit/hyperactivity disorder (ADHD)-combined type. It transitioned into an observational long-term follow-up of 515 cases consented for continuation and 289 classmates (258 without ADHD) added as a local normative comparison group (LNCG), with assessments 2-16 years after baseline. METHODS: Primary (symptom severity) and secondary (adult height) outcomes in adulthood were specified. Treatment was monitored to age 18, and naturalistic subgroups were formed based on three patterns of long-term use of stimulant medication (Consistent, Inconsistent, and Negligible). For the follow-up, hypothesis-generating analyses were performed on outcomes in early adulthood (at 25 years of age). Planned comparisons were used to estimate ADHD-LNCG differences reflecting persistence of symptoms and naturalistic subgroup differences reflecting benefit (symptom reduction) and cost (height suppression) associated with extended use of medication. RESULTS: For ratings of symptom severity, the ADHD-LNCG comparison was statistically significant for the parent/self-report average (0.51 ± 0.04, p < .0001, d = 1.11), documenting symptom persistence, and for the parent/self-report difference (0.21 ± 0.04, p < .0001, d = .60), documenting source discrepancy, but the comparisons of naturalistic subgroups reflecting medication effects were not significant. For adult height, the ADHD group was 1.29 ± 0.55 cm shorter than the LNCG (p < .01, d = .21), and the comparisons of the naturalistic subgroups were significant: the treated group with the Consistent or Inconsistent pattern was 2.55 ± 0.73 cm shorter than the subgroup with the Negligible pattern (p < .0005, d = .42), and within the treated group, the subgroup with the Consistent pattern was 2.36 ± 1.13 cm shorter than the subgroup with the Inconsistent pattern (p < .04, d = .38). CONCLUSIONS: In the MTA follow-up into adulthood, the ADHD group showed symptom persistence compared to local norms from the LNCG. Within naturalistic subgroups of ADHD cases, extended use of medication was associated with suppression of adult height but not with reduction of symptom severity.

Development and validation of a streamlined autism case confirmation approach for use in epidemiologic risk factor research in prospective cohorts.

The cost associated with incorporating standardized observational assessments and diagnostic interviews in large-scale epidemiologic studies of autism spectrum disorders (ASD) risk factors can be substantial. Streamlined approaches for confirming ASD case status would benefit these studies. We conducted a multi-site, cross-sectional criterion validity study in a convenience sample of 382 three-year olds scheduled for neurodevelopmental evaluation. ASD case classification as determined by three novel assessment instruments (the Early Video-guided Autism Screener E-VAS; the Autism Symptom Interview, ASI; the Screening Tool for Autism in Toddlers Expanded, STAT-E) each designed to be administered in less than 30 minutes by lay staff, was compared to ADOS scores and DSM-based diagnostic assessment from a qualified clinician. Sensitivity and specificity of each instrument alone and in combination were estimated. Alternative cutpoints were identified under different criteria and two-stage cross validation was used to avoid overfitting. Findings were interpreted in the context of a large, prospective pregnancy cohort study utilizing a two-stage approach to case identification. Under initial cutpoints, sensitivity ranged from 0.63 to 0.92 and specificity from 0.35 to 0.70. Cutpoints giving equal weight to sensitivity and specificity resulted in sensitivity estimates ranging from 0.45 to 0.83 and specificity ranging from 0.49 to 0.86. Several strategies were well-suited for application as a second-stage case-confirmation. These included the STAT-E alone and the parallel administration of both the E-VAS and the ASI. Use of more streamlined methods of case-confirmation in large-scale prospective cohort epidemiologic investigations of ASD risk factors appears feasible. Autism Res 2017, 10: 485-501. © 2016 International Society for Autism Research, Wiley Periodicals, Inc.