An Individual Participant Data Meta-analysis: Behavioral Treatments for Children and Adolescents With Attention-Deficit/Hyperactivity Disorder

Objective Behavioral interventions are well established treatments for children with attention-deficit/hyperactivity disorder (ADHD). However, insight into moderators of treatment outcome is limited. Method We conducted an individual participant data meta-analysis (IPDMA), including data of randomized controlled behavioral intervention trials for individuals with ADHD Results For raters most proximal to treatment, small- to medium-sized effects of behavioral interventions were found for symptoms of ADHD, inattention, hyperactivity/impulsivity (HI), ODD and CD, and impairment. Blinded outcomes were available only for small preschool subsamples and limited measures. CD symptoms and/or diagnosis moderated outcome on ADHD, HI, ODD, and CD symptoms. Single parenthood moderated ODD outcome, and ADHD severity moderated impairment outcome. Higher baseline CD or ADHD symptoms, a CD diagnosis, and single parenthood were related to worsening of symptoms in the untreated but not in the treated group, indicating a protective rather than an ameliorative effect of behavioral interventions for these children. Conclusion Behavioral treatments are effective for reducing ADHD symptoms, behavioral problems, and impairment as reported by raters most proximal to treatment. Those who have severe CD or ADHD symptoms, a CD diagnosis, or are single parents should be prioritized for treatment, as they may evidence worsening of symptoms in the absence of intervention

Picophytoplankton in freshwater ecosystems: the importance of small-sized phototrophs

About 40 years have passed since the discovery of picophytoplankton; the present knowledge of the taxonomy, physiology and ecology of these tiny photoautotrophic cells offers new perspectives on the importance of the microbial contribution to global biogeochemical cycles and food webs. This review focuses on the relationships among the components of picophytoplankton (picocyanobacteria and the picoplanktic eukaryotes) and biotic and abiotic environmental factors. The dynamics of picophytoplankton in aquatic ecosystems are strictly dependent upon basin size and trophy, temperature, and nutrient and light limitation, but they are also regulated by grazing and viral-induced lysis. The review considers: the pros and cons of the molecular approach to the study of the taxonomy of freshwater Synechococcus spp.; the importance of ecological aspects in understanding the puzzle of picophytoplankton phylogeny (genotype vs ecotype); and the role of biotic vs abiotic interactions in controlling picophytoplankton dynamics. Biotic, top-down control mechanisms are reviewed as well as knowledge of other biological interactions