Download This Paper
Preprints with The Lancet is part of SSRN´s First Look, a place where journals identify content of interest prior to publication. Authors have opted in at submission to The Lancet family of journals to post their preprints on Preprints with The Lancet. The usual SSRN checks and a Lancet-specific check for appropriateness and transparency have been applied. Preprints available here are not Lancet publications or necessarily under review with a Lancet journal. These preprints are early stage research papers that have not been peer-reviewed. The findings should not be used for clinical or public health decision making and should not be presented to a lay audience without highlighting that they are preliminary and have not been peer-reviewed. For more information on this collaboration, see the comments published in The Lancet about the trial period, and our decision to make this a permanent offering, or visit The Lancet´s FAQ page, and for any feedback please contact preprints@lancet.com.
Autism in the UK: Investigating Underdiagnosis in a Population-Based Cohort
27 Pages Posted: 1 Nov 2022
More...Abstract
Background: Autism has long been viewed as a paediatric condition, resulting in a ‘lost generation’ of autistic adults not diagnosed as children when autism was little known. We estimated numbers of diagnosed and undiagnosed UK autistic people, and examined how diagnostic rates differed by socio-demographic factors.
Methods: This population-based cohort study of prospectively collected primary care data from the IQVIA medical research database compared prevalence of diagnosed autism to community prevalence to estimate underdiagnosis. 1,840,036 individuals registered at a UK primary care practice in 2018 and 8,292,873 individuals registered between 2000 and 2018 were included.
Findings: As of 2018, 0.74% of people in the database were diagnosed autistic: 1.15% of males and 0.33% of females. Diagnostic rates were higher in children/young people vs. adults and older adults: 2.84% of 10-14-year-olds were diagnosed (1 in 35), vs. 0.02% aged 70+ (1 in 5,000). As of 2018, an estimated 526,700 people (0.79% of the UK population) were diagnosed autistic, and an estimated 509,700 to 1,436,300 were autistic but undiagnosed (59-73% of autistic people, 0.76%-2.14% of the population). Efforts to improve access to adult diagnostic assessments have not yet been effective: in 2018, c.1 in 200 5-9-year-olds were newly diagnosed vs. 1 in 3,400 20–49-year-olds, and 1 in 15,000 aged 50+.
Interpretation: Major age-related inequalities in access to autism diagnoses necessitate a step-change in access to diagnostic services.
Funding: Dunhill Medical Trust, Economic and Social Research Council, Medical Research Council, National Institute of Health Research, the Wellcome Trust, and the Royal College of Psychiatrists.
Declaration of Interest: P, RC, CC, AC, FH, JM, and RS declare no support from any organisation for the submitted work. EO received a post-doctoral fellowship from the Dunhill Medical Trust which funded completion of the work (grant awarded to JS and WM). JS was supported by the ESRC and NIHR. MR was supported by the Medical Research Council and JB was supported by the Wellcome Trust and the Royal College of Psychiatrists. CZ received honoraria for consultation on the AUDIT-50 project. All authors declare that they have no financial relationships with any organisations that might have an interest in the submitted work in the previous three years, and no other relationships or activities that could appear to have influenced the submitted work
Ethical Approval: IMRD holds ethical approval to collect and supply data for research purposes from the NHS London – South East Research Ethics Committee (reference 18/LO/0441). Use of the IMRD for this study was obtained and approved by IQVIA World Publications Scientific Review Committee in June 2021 (reference 21SRC014).
Keywords: autism spectrum condition, primary care, underdiagnosis, under-diagnosis, incidence, prevalence
Suggested Citation: Suggested Citation