Neurodevelopmental diagnoses delayed in girls

Takeaway

• Girls tend to be diagnosed with several neurodevelopmental conditions later than boys, suggesting some delay in detection.
• Overall, 15.01% of children received a neurodevelopmental or mental health-related diagnosis by age 18 years.

Why this matters

• The prevalences and sex-based differences in diagnoses and their timing form a basis for public health care and planning of services, the authors say.
• Clinicians can be alert to these differences and the potential for sex bias in the timing of diagnosis.

Key results

• 15.01% (95% CI, 14.98%-15.17%) were diagnosed with at least 1 mental health/neurodevelopmental condition by age 18 years.
• 14.63% (95% CI, 14.48%-14.77%) girls were diagnosed compared with 15.51% (95% CI, 15.18%-15.84%) boys.
• Anxiety was most common among girls (7.85%; 95% CI, 7.74%-7.97%).
• ADHD was most common among boys (5.90%; 95% CI, 5.76%-6.03%).
• Girls had a higher risk for schizophrenia, obsessive-compulsive disorder, and mood disorders.
• Diagnostic rates of ADHD, autism, intellectual disability, and other neurodevelopmental diagnoses peaked at an earlier age among boys (early childhood) than among girls (teens).

Study design

• Danish cohort study, data for 1.3 million children born during 1995-2016.
• 99,926 (41,350 girls; 58,576 boys) had 1 diagnosis before age 18 years.
• Funding: Lundbeck Foundation; Aarhus University Research Foundation; Novo Nordisk Foundation; others.

Limitations

• Cohort effects are possible, including changing patterns of referral, social attitudes, resources.