Informing the pediatric mental health recovery plan: evaluating delays to diagnoses and changing characteristics of children and adolescents with new neurodevelopmental and mental health disorders in Ontario, Canada during the COVID-19 pandemic.

Neurodevelopmental and mental health disorders frequently emerge and are diagnosed in childhood and adolescence. Early detection and treatment are critical to ensure optimal health outcomes across the lifespan. During the COVID-19 pandemic, widespread closures of in-person activities and learning for children and adolescents as well as changes in access to health care have posed new challenges for early identification of neurodevelopmental (e.g. developmental delay, autism spectrum disorder, and attention deficit hyperactivity disorder) and mental health disorders (e.g., mood, anxiety, psychotic, substance use, eating, and other mental disorders). In addition, pandemic-related stressors (e.g., loss of connection with peers, increased screen time, reduced physical activity) may have triggered or worsened symptoms of mental health disorders among those who have not previous sought care. With our mental and developmental health systems already at capacity, the consequences of population-wide delays in diagnoses and shifts in who is affected and for which mental health disorders during a critical window of development may have profound implications on service provision needs downstream following the pandemic. Using well-established linked administrative and health datasets in Ontario, our study aims to understand the extent of delays to diagnosis and changing socio-demographic (e.g. age at diagnosis, sex, social vulnerability) and clinical characteristics (e.g. type of disorder, acuity of presentation) of children and adolescents with new neurodevelopmental and mental health disorders during the pandemic. We will compare the rates and characteristics of all children/adolescents with new diagnoses of neurodevelopmental and mental health disorders in the two years before and after the onset of the COVID-19 pandemic. This information is critical to informing our pandemic recovery plan across health, education, and community sectors to ensure adequate and targeted supports.