Prior to analysis, we did some initial data quality assurance, by excluding individuals who did not complete at least two blocks of trials and individuals who responded less than click here chance across multiple blocks. Analytic approach To establish construct validity of our Web-based adaptations of these widely used lab paradigms beyond face validity, we used a convergent validity approach frequently used in other forms of psychological testing (Messick 1989; McDonald 1999). We sought to determine: (a) if the pattern of association between the different tasks matches the pattern predicted by the relationship between the constructs they are Inhibitors,research,lifescience,medical assumed to tap into; (b) if the pattern of association

between the different cognitive task and attention symptoms matches the pattern of association predicted by the relationship between the underlying constructs; and (c) use the dyadic nature of the data to determine if the relationship between the child’s score on the different cognitive test and the

Inhibitors,research,lifescience,medical parents score on the same test matches the degree to which neurocognitive endophenotypes are assumed to be heritable. Results Web sample characterization Our initial goal was to characterize a large completely Web-recruited community sample without Inhibitors,research,lifescience,medical a diagnosis of ADHD on cognitive and symptom characteristics related to cognitive control. These data help provide normative data for Web-based cognitive test studies and begin to characterize those families who participate in Web-based studies. Table ​Table22 highlights the cognitive test performance and the association with attention symptoms as well as the correlation in scores Inhibitors,research,lifescience,medical between parents and their offspring. Figure ​Figure22

shows the distribution of symptom sums for the children and adolescents in our sample. Table 2 Performance characteristics on cognitive measures shows the raw scores for cognitive tests and statistics for comparison between family members Figure 2 Distribution of symptoms shows the histogram for symptom sum in our adolescent Web sample. Y-axis shows frequency and X-axis shows sum total symptoms for each participant. Inhibitors,research,lifescience,medical Data report symptom scores for 219 adolescent participants TCL as filled out by the … Construct validation We examined the relationship between working memory and response inhibition measures to demonstrate an inverse relationship between the constructs in both children and parents (Table ​(Table3).3). The overall pattern of results is consistent across parents and their children: The expected correlation between the constructs of about 0.35 holds true for the relationship between response inhibition and working memory RT across all four load conditions. The data show internal validity with increased RT for higher working memory load and decreased accuracy (Fig. ​(Fig.3).3). Both tasks also showed strong reliability. The working memory task produced alphas that ranged from 0.81–0.