Systematic Review of the Tools Used for Diagnosis of Attention-Deficit / Hyperactivity Disorder (ADHD) in Preschoolers

Given the importance of early diagnosis of Attention-Deficit / Hyperactivity Disorder (ADHD) on the one hand and the heterogeneity of ADHD among preschoolers, on the other hand, this study aimed at examining the tools used to diagnose ADHD in preschoolers. According to PRISMA guidelines, we searched for articles indexed in the Scopus, ProQuest, ScienceDirect, and Sage databases from 2015 to 2021, using a combination of expressions including "ADHD" or "ADD" or "Attention" Deficit Disorder ”(and“ preschooler ”or“ 3-6-year-olds ”) and (“ assessment ”or“ measurement ”). Eighteen empirical studies were identified as relevant to our research. The studies were evaluated in two stages: first, the agreement between the two reviewers was calculated using Cohen's Kappa coefficient (r=0.87), and none of the articles was removed. Secondly, each study was assessed based on bias, confounders, power, and strength of association between intervention and outcomes using the Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies. The findings demonstrated that the tools in this area can be divided into two general categories: questionnaires of reporting parents and teachers and observing children's actions and behavior. And tacks of observing children's actions and behavior are divided into two categories: cognitive inhibition and behavioral inhibition tests. In conclusion, the diagnosis of preschoolers with ADHD requires a multi-method approach with multiple information and must be based on both reporting and Nero-psychological methods.