Summary scores from these nine items www.selleckchem.com/products/Lenalidomide.html create three scales (Hu, Davies, & Kandel, 2006; Pomerleau et al., 1998): (a) dizziness; (b) pleasant symptoms (pleasant sensations, relaxation, pleasurable rush, or buzz); (c) unpleasant symptoms (unpleasant sensations, nausea, coughing, difficulty inhaling, and heart pounding). Consistent with prior studies (Hu et al., 2006), these scales were grouped into pleasant (Cronbach’s alpha = .78) and unpleasant (Cronbach��s alpha = .79) initial reactions index scores for the analysis. ADHD Symptoms Participants retrospectively reported on DSM-IV ADHD symptoms in childhood (between 5 and 12 years) using a 4-point scale: never or rarely, sometimes, often, or very often. One DSM-IV impulsivity symptom (��often interrupts or intrudes on others��) was not included in the retrospective ADHD section.

Thus, our analyses included responses to nine inattentive (IN) and eight hyperactive�Cimpulsive (HI) symptoms. A symptom was considered present if it was experienced often or very often (Murphy & Barkley, 1996). For our primary analyses, individuals were classified into one of two groups for each symptom domain based on the number of symptoms reported at a level of ��often�� or ��very often��. The six-symptom cutoff was chosen to be consistent with DSM-IV ADHD criteria requiring the presence of six or more symptoms from either the IN or the HI symptom domains. Data Analyses Statistical analyses were conducted using SAS-callable SUDAAN (version 8.0) software. SUDAAN allows for control of survey design effects of individuals clustered in a sampling unit of school and stratification of geographic region.

Linear regressions were used to determine whether candidate genotypes predicted the pleasant or unpleasant initial reaction index scores. The specific genotypes were grouped for analysis according to the extant literature and are listed in Supplementary Table 1 (Hu et al., 2006; Munafo et al., 2004; Todd et al., 2005). Separate models were evaluated for each polymorphism using the Taylor Linearization method. The models were constructed to include main effects of the polymorphism, ADHD symptoms (IN or HI), and the interaction between polymorphisms and ADHD symptoms in predicting both pleasant and unpleasant initial reactions. Brefeldin_A Age, race, parental education level, and the presence or absence of CD were included as covariates. Results Results for all models are listed in Supplementary Table 1. No main effects were observed for any of the genotypes predicting either pleasant or unpleasant initial reactions. The following Genotype �� ADHD Symptom interactions were found: DRD2 We observed a significant Taq1A DRD2 �� HI interaction predicting pleasant initial reactions (p = .