Journal of the American Academy of Child & Adolescent Psychiatry
ReviewWhat Is the Male-to-Female Ratio in Autism Spectrum Disorder? A Systematic Review and Meta-Analysis
Section snippets
Method
We followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines for systematic reviews.
Overview
Figure 1 depicts the process by which studies were identified. Fifty-four met the inclusion criteria, consisting of 13,784,284 participants, 53,712 of whom were diagnosed with ASD (43,972 boys and 9,740 girls). Details of each study, including total risk-of-bias score, are presented in Table S1 (available online). Fourteen studies were conducted in North America, with 11 taking place in the United States21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31 and 3 in Canada.32, 33, 34 Twenty-four were
Discussion
We conducted the first meta-analysis of the ASD male-to-female ratio based on a systematic review of epidemiologic prevalence studies reported according to PRISMA guidelines. The overall weighted MFOR (4.20; 95% CI 3.84–4.60), derived from 54 prevalence studies, was consistent with DSM-5’s assertion that among diagnosed cases, there are 4 boys for every girl on the autism spectrum.1 However, there was significant and very substantial variability among the 54 studies, which calls into question
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Dr. Loomes was supported by Health Education England.
The authors thank Vyv Huddy, PhD, of the UCL Research Department of Clinical, Educational and Health Psychology, for his support with planning and conducting the meta-analysis.
Disclosure: Drs. Loomes and Mandy and Ms. Hull report no biomedical financial interests or potential conflicts of interest.