The prevalence of DSM-IV attention-deficit/hyperactivity disorder:
A meta-analytic review
Erik G. Willcutt
Citation: Willcutt, E. G. (2012). The prevalence of DSM-IV attention-deficit/hyperactivity disorder: A meta-analytic review. Neurotherapeutics, 9, 490-499.
Abstract / Overview. This article describes a comprehensive meta-analysis that was conducted to estimate the prevalence of DSM-IV ADHD. A systematic literature review identified 86 studies of children and adolescents (N = 163,688 individuals) and 11 studies of adults (N = 14,112 individuals) that met inclusion criteria for the meta-analysis, over half of which were published after the only previous meta-analysis of the prevalence of ADHD was completed. Although prevalence estimates reported by individual studies varied widely, pooled results suggest that the prevalence of DSM-IV ADHD is similar whether ADHD is defined by parent ratings, teacher ratings, or a best estimate diagnostic procedure in children and adolescents (5.9 - 7.1%), or by self-report measures in young adults (5.0%). Analyses of diagnostic subtypes indicated that the predominantly inattentive type is the most common subtype in the population, but individuals with the combined type are more likely to be referred for clinical services. Additional research is needed to determine the etiology of the higher prevalence of ADHD in males than females and to clarify whether the prevalence of ADHD varies as a function of socioeconomic status or ethnicity. Finally, there were no significant prevalence differences between countries or regions of the world after controlling for differences in the diagnostic algorithms used to define ADHD. These results provide important support for the diagnostic validity of ADHD, and argue against the hypothesis that ADHD is a cultural construct that is restricted to the United States or any other specific culture.
Relation of this paper to the DSM-5 Workgroup. Dr. Willcutt is a consultant to the DSM-5 ADHD and Disruptive Behavior Disorders Work Group. The current review is an extension of a comprehensive meta-analysis of the validity of DSM-IV ADHD symptom dimensions and subtypes that was completed in collaboration with several members of the work group and additional co-authors (http://psych.colorado.edu/~willcutt/dsmiv.htm). I thank the co-authors of the larger meta-analysis (Joel Nigg, Bruce Pennington, Rosemary Tannock, Mary Solanto, Luis Rohde, Keith McBurnett, Caryn Carlson, Sandra Loo, and Ben Lahey) for constructive feedback on earlier versions of this article. The opinions expressed in the final version of this article are mine alone, and do not reflect official positions of the American Psychiatric Association, the DSM-5 Workgroup, or my co-authors on the overall meta-analysis.
Acknowledgements. The author was supported during the preparation of this manuscript by NIH grants R01 HD 68728, HD 47264, R01 MH 63207, P50 HD 27802, P50 MH 79485, R01 DA 24002, R01 MH 63941, and R01 MH 62120. I thank Cinnamon Bidwell and Sena-Hitt Laustsen for their assistance with the literature search and data consolidation, and thank Nomita A. Chhabildas for helpful comments on the manuscript.
Preprints. To provide timely access to the results of the review, links to PDF versions of the main paper and supplemental materials are provided below.
Body of the paper: PDF
Supplemental tables: PDF