A meta-analysis of 175 research studies worldwide on ADHD prevalence in children aged 18 and under found an overall pooled estimate of 7.2% (Thomas et al. 2015). The US Census Bureau estimates 1,795,734,009 people were aged 5-19 worldwide in 2013. Thus, 7.2% of this total population is 129 million—a rough estimate of the number of children worldwide who have ADHD.
Based on DSM-IV screening of 11,422 adults for ADHD in 10 countries in the Americas, Europe and the Middle East, the estimates of worldwide adult ADHD prevalence averaged 3.4% (Fayyad et al. 2007)
Children & Adolescents
Analysis of parent-reported data from the National Health Interview Survey (NHIS) 2011–2013 found the following (Pastor et al. 2015):
The same study found the rate of ADHD diagnosis increased from 7.0% in 1997–1999 to 10.2% in 2012–2014. During this period, prevalence increased among non-Hispanic white children from 8.5% to 12.5%, among non-Hispanic black children from 5.5% to 9.6%, and among Hispanic children from 3.8% to 6.4%.
The National Survey of Children’s Health (NSCH) 2003–2011—based on parent interviews—highlights the following data for children aged 4–17 (US CDC 2014):
Children in Elementary School
According to a recent population-based study using DSM-IV criteria, 15.5% of school children enrolled in Grades 1 to 5 have ADHD. The study combined the results of rating scales filled out by teachers and telephone interviews of parents for 7,847 children (Rowland et al. 2015).
According to a screen for ADHD in 3,199 adults aged 18–44 from the National Comorbidity Survey Replication (NCS-R), 4.4% of US adults have ADHD. Of these adults with ADHD, 38% are women and 62% are men (Kessler et al. 2006).
Fayyad J. et al. (May 2007). Cross-national prevalence and correlates of adult attention-deficit hyperactivity disorder. British Journal of Psychiatry, 190(5):402–409. http://dx.doi.org/10.1192/bjp.bp.106.034389
Pastor, Patricia N. (August 28, 2015). QuickStats: Percentage of Children and Adolescents Aged 5–17 Years with Diagnosed Attention-Deficit/Hyperactivity Disorder (ADHD), by Race and Hispanic Ethnicity — National Health Interview Survey, United States, 1997–2014, Morbidity and Mortality Weekly Report (MMWR) 64(33):925–925.
Pastor, Pastor N. et al. (2015). Association between diagnosed ADHD and selected characteristics among children aged 4–17 years: United States, 2011–2013. NCHS data brief, no 201. Hyattsville, MD: National Center for Health Statistics.
Ronald C. Kessler et al. (April 2006). The Prevalence and Correlates of Adult ADHD in the United States: Results From the National Comorbidity Survey Replication, American Journal of Psychiatry 163(5):71.
Rowland, Andrew et al. (September 2015). The Prevalence of ADHD in a Population-Based Sample. Journal of Attention Disorders v19(9):741–754.
Thomas, Rae et al. (April 2015). Prevalence of Attention-Deficit/Hyperactivity Disorder: A Systematic Review and Meta-analysis. Pediatrics, 135(4), pp. e994–e1001.
U.S. Centers for Disease Control and Prevention (2014). Key Findings: Trends in the Parent-Report of Health Care Provider-Diagnosis and Medication Treatment for ADHD: United States, 2003–2011.
US. Census Bureau, Population Division. World Midyear Population by Age and Sex for 2013