Development of a Short Version of the ADHD Rating Scale-IV.es (sADHD-RS-IV.es).

OBJECTIVE: To develop a short version of the Spanish 18-item ADHD-Rating Scale IV.es (sADHD-RS-IV.es) to be used as a potential screening tool in pediatric population. METHODS: We recruited 652 subjects, ages 6 to 18 (mean ± SD = 11.14 ± 3.27): 518 patients with ADHD (per DSM-IV criteria); and 134 healthy controls. We performed a stepwise logistic regression to select the best subset of ADHD-RS-IV.es items to create a short-form. We calculated internal consistency reliability (Cronbach's and ordinal alphas) and diagnostic accuracy using receiver operating characteristic (ROC) curve. RESULTS: Six items were found to enter the stepwise analysis significantly. Internal consistency was high (Cronbach's alpha = 0.86; ordinal alpha = 0.90) and offered a good concordance with clinician diagnosis and a high discriminatory power (AUC = 0.98) with an optimal cut-off at a score of six points. CONCLUSIONS: This shorter questionnaire (six items) was able to discriminate ADHD cases from healthy controls.

Time discrimination and change detection could share a common brain network: findings of a task-based fMRI study.

Introduction: Over the past few years, several studies have described the brain activation pattern related to both time discrimination (TD) and change detection processes. We hypothesize that both processes share a common brain network which may play a significant role in more complex cognitive processes. The main goal of this proof-of-concept study is to describe the pattern of brain activity involved in TD and oddball detection (OD) paradigms, and in processes requiring higher cognitive effort. Methods: We designed an experimental task, including an auditory test tool to assess TD and OD paradigms, which was conducted under functional magnetic resonance imaging (fMRI) in 14 healthy participants. We added a cognitive control component into both paradigms in our test tool. We used the general linear model (GLM) to analyze the individual fMRI data images and the random effects model for group inference. Results: We defined the areas of brain activation related to TD and OD paradigms. We performed a conjunction analysis of contrast TD (task > control) and OD (task > control) patterns, finding both similarities and significant differences between them. Discussion: We conclude that change detection and other cognitive processes requiring an increase in cognitive effort require participation of overlapping functional and neuroanatomical components, suggesting the presence of a common time and change detection network. This is of particular relevance for future research on normal cognitive functioning in the healthy population, as well as for the study of cognitive impairment and clinical manifestations associated with various neuropsychiatric conditions such as schizophrenia.