The childhood executive functioning inventory (CHEXI): a new rating instrument for parents and teachers.

Poor executive functioning has been shown to be of central importance in disruptive behavior disorders such as attention deficit hyperactivity disorder (ADHD), and a large number of laboratory measures of executive functioning have been developed. There are, however, few available questionnaires tapping executive functioning and those that exist also include items focused directly on the symptom criteria for ADHD, which makes it difficult to draw conclusions regarding executive functioning per se. In the present study, a new rating instrument, the Childhood Executive Functioning Inventory (CHEXI) was therefore introduced. This instrument was shown to have good test-retest reliability. Using factor analysis, two factors tapping working memory and inhibition emerged using parent ratings and these two factors were replicated using teacher ratings. Modest, yet mostly significant, relations to laboratory measures of working memory and inhibition were found. Ratings on the CHEXI were also found to be significantly related to ADHD symptoms as well as early academic achievement. Interestingly, ratings on the CHEXI and laboratory measures of working memory and inhibition were shown to explain independent variance in ADHD symptoms and academic achievement, which point to the importance of using a multi-assessment strategy when studying executive functioning.

Early concurrent and longitudinal symptoms of ADHD and ODD: relations to different types of inhibitory control and working memory.

BACKGROUND: The aim of the present study was to investigate how three different types of inhibitory control - interference control within task, interference control outside task, and prepotent response inhibition - and two types of working memory - verbal and spatial - would relate to early symptoms of attention deficit/hyperactivity disorder (ADHD) and oppositional defiant disorder (ODD), both concurrently and longitudinally. METHODS: Seventy-two preschoolers, 1/3 who had been identified as being at risk for developing ADHD and/or ODD, completed neuropsychological tasks designed to measure inhibitory control and working memory. Behavioral symptoms were measured through parental and teacher ratings of the DSM-IV criteria for ADHD and ODD. RESULTS: Our results suggest distinct types of inhibitory control as being good predictors of concurrent and longitudinal symptoms of ADHD, rather than ODD. However, no associations were obtained between working memory and ADHD or ODD symptoms either concurrently or longitudinally. CONCLUSIONS: This study emphasizes the need to isolate complex executive processes and break them down into components in order to properly understand the neuropsychological roots involved in ADHD and ODD.

Assessing Type A behavior in children: a longitudinal exploration of the overlap between Type A behavior and hyperactivity.

Child Type A behavior and its relation to hyperactivity were investigated developmentally using a longitudinal normal sample of 91 children (46 boys and 45 girls) between the ages of 4 and 8-9. In light of the overlap found in several studies between Type A behavior, as measured by the Matthews Youth Test for Health (MYTH) questionnaire, and hyperactivity measured by questionnaires, an attempt was made to measure Type A behavior as distinct from hyperactivity using behavioral observations. The MYTH questionnaire and behavioral observations were used to assess Type A behavior and questionnaire-based measures and behavioral observations were used to assess hyperactivity. Predictions were made regarding individual stability in phenomena and in measures. The results indicated considerable stability in the respective Type A and hyperactivity measures over time, and further, that behavioral observations make it possible to measure Global Type A behavior and Type A Competitiveness as distinct from hyperactivity, although the status of Type A Impatience at early ages is not yet settled. The MYTH and the observed Type A behavior showed differential relations to external criteria, such as achievement measures and problem behavior. This has implications for future measurement and perhaps conceptualization of Type A behavior in children, and thereby also for studying the developmental aspects of Type A behavior.

How well do measures of inhibition and other executive functions discriminate between children with ADHD and controls?

The aim of the present study was to evaluate the usefulness of Barkley's (1997a) model of inhibition and executive functioning in describing the deficits associated with Attention Deficit Hyperactivity Disorder (ADHD). Besides group differences, the present study addressed the question of independent effects of inhibition and the other executive functions in discriminating between children with ADHD and controls and how well, in terms of sensitivity and specificity, these measures can classify the children into the correct group. The results showed that children with ADHD differed significantly from controls with regard to measures of inhibition as well as all other executive function measures, except repetition of hand movements. In logistic regression models, three different measures tapping inhibition, working memory and emotion regulation were shown to be significant independent predictors of group membership. The sensitivity for these three variables as a set was 76.2, the specificity was 90.5, with a total of 86% of the sample correctly classified. When excluding the parental rating of emotion regulation, the overall classification rate decreased some, but was still relatively high in comparison with previous studies within this area of research.

Inhibition and executive functioning in Type A and ADHD boys.

The present study was aimed at clarifying the standing of Type A behavior, as measured by behavioral observations, relative to Attention Deficit Hyperactivity Disorder (ADHD), using measures of inhibitory control and executive functioning. The study sample included 20 boys exhibiting Type A behavior, 21 boys exhibiting Type B behavior and 14 boys diagnosed with ADHD, ranging in age from 7 to 12 years. The results of the present study showed that the Type A children differed from Type B children on two time-related variables, response latency and reaction time, in accordance with the view of Type As as time-urgent and impatient. Furthermore, in comparisons with the ADHD group, the Type A boys were found to be superior on several performance tasks, such as Go/no-go omissions, time reproduction, story recall and memory for sequences of hand movements, although similarities between Type A and ADHD boys were evidenced in terms of response latency and reaction time. In other words, although Type A boys were similar to ADHD boys in terms of overt displays of time-urgency and impatience, Type As do not display deficits with regard to executive functioning, of the kind often found when ADHD children are compared with normal controls. It may thereby be concluded that Type A behavior and hyperactivity/ADHD appear to be well differentiated except with regard to what may be interpreted as impatience. Speculations concerning differing origins of overtly similar characteristics of Type A behavior and ADHD should be considered in future research.