Recent studies estimate the prevalence of autism-spectrum conditions in the UK to be 1%. A study in Cambridgeshire used multiple methods to estimate the prevalence, including previously undiagnosed cases. The study involved a survey of autism-spectrum conditions using the Special Educational Needs (SEN) register and a diagnosis survey distributed to parents of children aged 5–9 years. The prevalence estimates generated from the SEN register and diagnosis survey were 94 per 10,000 and 99 per 10,000, respectively. After screening and assessment, 11 children received a research diagnosis of an autism-spectrum condition. The ratio of known:unknown cases was about 3:2, leading to an estimated prevalence of 157 per 10,000, including previously undiagnosed cases. The study found that autism-spectrum conditions are diagnosed based on social and communication difficulties, along with unusual interests and repetitive behaviors. The prevalence of autism-spectrum conditions has increased over the past four decades, with estimates for classic autism being 4 in 10,000 in 1978 and approximately 1% today. This increase is attributed to improved recognition, changes in study methods, increased diagnostic services, and greater awareness. The study used a novel approach by screening the mainstream primary school population to detect potential undiagnosed cases. The Autism Spectrum Screening Questionnaire (ASSQ) was used to identify children with high or borderline scores. The study found that 11 children were diagnosed with autism-spectrum conditions, with 4 meeting criteria for childhood autism. The study also found that the prevalence of autism-spectrum conditions in the population was estimated to be 157 per 10,000, including previously undiagnosed cases. The study highlights the importance of considering the continuous distribution of autistic traits in the general population and the need for more accurate diagnostic criteria. The study also notes that the prevalence estimates may vary due to differences in methodologies and sampling. The study concludes that the prevalence of autism-spectrum conditions is slightly above 1%, and that the findings support the need for appropriate services to meet the needs of between 1–2% of the primary school-aged population.Recent studies estimate the prevalence of autism-spectrum conditions in the UK to be 1%. A study in Cambridgeshire used multiple methods to estimate the prevalence, including previously undiagnosed cases. The study involved a survey of autism-spectrum conditions using the Special Educational Needs (SEN) register and a diagnosis survey distributed to parents of children aged 5–9 years. The prevalence estimates generated from the SEN register and diagnosis survey were 94 per 10,000 and 99 per 10,000, respectively. After screening and assessment, 11 children received a research diagnosis of an autism-spectrum condition. The ratio of known:unknown cases was about 3:2, leading to an estimated prevalence of 157 per 10,000, including previously undiagnosed cases. The study found that autism-spectrum conditions are diagnosed based on social and communication difficulties, along with unusual interests and repetitive behaviors. The prevalence of autism-spectrum conditions has increased over the past four decades, with estimates for classic autism being 4 in 10,000 in 1978 and approximately 1% today. This increase is attributed to improved recognition, changes in study methods, increased diagnostic services, and greater awareness. The study used a novel approach by screening the mainstream primary school population to detect potential undiagnosed cases. The Autism Spectrum Screening Questionnaire (ASSQ) was used to identify children with high or borderline scores. The study found that 11 children were diagnosed with autism-spectrum conditions, with 4 meeting criteria for childhood autism. The study also found that the prevalence of autism-spectrum conditions in the population was estimated to be 157 per 10,000, including previously undiagnosed cases. The study highlights the importance of considering the continuous distribution of autistic traits in the general population and the need for more accurate diagnostic criteria. The study also notes that the prevalence estimates may vary due to differences in methodologies and sampling. The study concludes that the prevalence of autism-spectrum conditions is slightly above 1%, and that the findings support the need for appropriate services to meet the needs of between 1–2% of the primary school-aged population.