ADHD and autism spectrum disorder are neurodevelopmental disorders affecting millions of children worldwide. It is estimated that 1 in 100 people in Australia are on the autism spectrum and around 1 in 30 adults has ADHD.
Both are commonly diagnosed in childhood, with ADHD typically identified between the ages of five to nine and autism between three and six years. Diagnosis is based on observing a child’s behaviours and their developmental history, because there are no physical or biological tests for these disorders. Adding to the complexity is that each condition can present in various ways. Yet timely diagnosis and intervention are crucial for improved outcomes in a child’s social life, mental health and education.
A recent study focusing on Australian children sought to understand these diagnostic delays more comprehensively. The research involved caregivers of almost 700 children with ADHD, autism or both, aged between one and 16. Participants reported when developmental concerns were first detected in their child, when they received an autism or ADHD diagnosis, and who gave that diagnosis. Other demographic data, like socio-economic status, were also recorded.
The study found that most children received their diagnosis in a private setting (more than three quarters). The findings reveal the complex relationships between different developmental disorders – showing children with ADHD and autism received their ADHD diagnosis earlier than those children who just had ADHD, but that the delay for a diagnosis of autism was longer for those children diagnosed autism and ADHD, versus those diagnosed with autism alone. Girls were diagnosed later than boys for both autism and ADHD.
The longer diagnostic delays for children with multiple conditions occurring at the same time, and for young girls, suggests a need for improved education and training for healthcare professionals. GPs are often the first contact for concerned parents and play a crucial role in the referral process. The authors suggest guidelines for diagnosing ADHD and autism where they co-occur are lacking and point to a need for more specialised training and awareness.
Further information
Age at diagnosis and diagnostic delay across attention-deficit hyperactivity and autism spectrums: Sage Journals
