Estimated Prevalence of Nonverbal Learning Disability Among North American Children and Adolescents

This secondary analysis of a cross-sectional study estimates the prevalence of the nonverbal learning disability cognitive profile in children and adolescents from studies centered around brain imaging in the US and Canada.


eMethods. Supplemental Methods
Population rates for known disorders Rates were selected from published prevalence reports using data obtained through diagnostic interview data or child performance measures, rather than parent report of a diagnosis via interview, whenever possible.
Rate of Attention Deficit Hyperactivity Disorder (ADHD) was obtained from the NIMH website (https://www.nimh.nih.gov/health/statistics/attention-deficit-hyperactivitydisorder-adhd.shtml). Data from National Comorbidity Survey-Adolescent Supplement (NCS-A) documents the lifetime prevalence of ADHD among U.S. adolescents aged 13 to 18 years as 8.7 percent.
Rate of Specific Learning Disability (SLD) was calculated based on information obtained from the National Center for Education Statistics website (https://nces.ed.gov/programs/coe/indicator_cgg.asp). The site reported that in 2017-18, 7 million children (14% of all public school students) received special education services, and of these 34 percent had SLD. Accordingly, 2,380,000 children (34% of those receiving special education services) of the total population of 50 million public school children had an SLD classification, yielding a prevalence of 4.8 percent.
Rate of Autism Spectrum Disorder (ASD) was obtained from the Center for Disease Control (CDC) website (https://www.cdc.gov/ncbddd/autism/addm.html). Data from the Autism and Developmental Disabilities Monitoring (ADDM) Network documents that 1 in 59 8-year old children met criteria for ASD.
Rate of anxiety was obtained from the NIMH website (https://www.nimh.nih.gov/health/statistics/any-anxiety-disorder.shtml). Data from National Comorbidity Survey Adolescent Supplement (NCS-A), documents that 31.9 percent of adolescents had any anxiety disorder.
Rate of major depression was obtained from the NIMH website (https://www.nimh.nih.gov/health/statistics/major-depression.shtml). Data from Substance Abuse and Mental Health Services Administration (SAMHSA) documents that in 2017, 13.3 percent of adolescents had had at least one major depressive episode.
Coding R code used for sample weighting procedures is available upon request.
Demographic characteristics of children who met criteria for NVLD The distribution of NVLD (N = 137) in HBN across demographic groups is similar to the overall breakdown of HBN (Table S3). The highest proportion of participants with NVLD were non-Hispanic White (42%) followed by Hispanic (24%), then Non-Hispanic Black (22%), and male participants made up 65% of those with NVLD. Participants above the poverty line made up the largest proportion of NVLD (69%) followed by those missing income (24%). Last, the age group with the most participants with NVLD was the 10-14 year olds (43%), followed by the 6-9 year olds (30%).