Diagnosis provision by young people's mental health services: a comparison with epidemiological data

Background Little is known about the provision of diagnoses to young people with mental health disorders. We investigated diagnosis provision by NHS mental health services, focusing on 17-year-olds in South London between 2009-2024, and compared with estimated disorder prevalence. Methods To examine diagnosis provision in the population, we extracted diagnosis data from records of the NHS mental healthcare provider serving South London, using the Maudsley Biomedical Research Centre Clinical Record Interactive Search application; we then compared these data with the corresponding population size, obtained from the Office for National Statistics. To assess diagnosis provision in those with mental health disorders, we compared diagnosis data with the number of young people estimated to have met criteria for a disorder, derived from epidemiological interview data collected in the Environmental Risk (E-Risk) Longitudinal Twin Study and weighted according to characteristics of 17-year-old South Londoners. To assess diagnosis provision in those with mental health disorders within health services, we compared diagnosis data with the number estimated to have met criteria for a disorder and used any health service for their mental health, again derived from weighted E-Risk Study data. Findings Of 17-year-olds from South London in 2009-2024, 4.0% (n=8,958/223,404) had a diagnosis in mental health records during the previous year. This diagnosis provision covered <1 in 16 of those estimated to have had a mental health disorder, and <1 in 4 of those estimated to have also used health services. Diagnosis provision was lower in girls than boys and in young people with Black/Asian/Mixed/Other ethnicity than those with White ethnicity, in those estimated to have had a mental health disorder and used health services. Interpretation These findings demonstrate gaps and biases in mental health diagnosis provision for young people, including within health services, and reveal the imperative need to strengthen young people's mental healthcare.