We compared the Wechsler scores of individuals with twice-exceptionality (2e) and giftedness using a three-level Bayesian meta-analysis. Ninety-five effect sizes were calculated from 15 studies (n = 2,106). Results show that individuals with 2e who have learning disabilities perform lower than individuals with giftedness in Full-Scale Intelligence…

Background: A body of literature has emerged that links inattentive symptoms of attention deficit hyperactivity disorder (ADHD) to poor academic achievement. Major variation across studies renders conclusions about this relationship complex. Purpose: This review will provide a qualitative synthesis of these studies that (1) use community samples…

Background: The efficacy of three dietary treatments for ADHD has been repeatedly tested in randomized controlled trials (RCTs). These interventions are restricted elimination diets (RED), artificial food colour elimination (AFCE) and supplementation with free fatty acids (SFFA). There have been three systematic reviews and associated…

Students with Attention Deficit Hyperactivity Disorders (ADHD) frequently experience significant difficulty mastering basic academic skills. This meta-analysis focuses on one specific potential area of learning difficulties for these students: namely, writing. To identify the extent and depth of the potential writing challenges faced by students…

Background: Evidence from Western countries indicates marked increases in diagnosis and treatment of childhood psychiatric disorders in recent years. These could reflect changes in prevalence of mental health problems, changes in their impact or increased clinical recognition and help-seeking. Epidemiological cross-cohort comparisons are required…

From different research perspectives, the cognitive and emotional characteristics associated with ADHD in children have been identified as risk factors for the development of diverse adjustment problems in the school context. Research in nonclinical population can additionally help in understanding ADHD deficits, since children with specific…

Objective: In recent years cohort studies have examined childhood attention-deficit/hyperactivity disorder (ADHD) as a risk factor for substance use disorders (SUDs) in adolescence and young adulthood. The long-term risk is estimated for development of alcohol, cannabis, combined alcohol and psychoactive SUDs, combined SUDs (nonalcohol), and…

Given the ongoing debate over whether giftedness is associated with mental health disorders, there is a great need to highlight and compare results from the most methodologically rigorous studies. Surprisingly, the vast majority of literature reviews and background sections of research articles include studies that do not directly compare gifted…

REL Appalachia conducted a systematic review of the research evidence on the effects of increased learning time. After screening more than 7,000 studies, REL Appalachia identified 30 that met the most rigorous standards for research. A review of those 30 studies found that increased learning time does not always produce positive results. However,…