More adults are getting assessed for possible autism. Here, we give an overview on what is already known about autism diagnosis in adulthood and find areas that need more research. We divided results from the studies we found into six topics of (1) rates of autism in different groups; (2) the process of getting an autism diagnosis in adulthood; (3) gender; (4) personality traits, abilities and behaviours of diagnosed adults; (5) mental and physical health conditions that occur together with autism; and (6) how adults think and feel about being assessed and diagnosed. We found that adults often have strong emotions after being diagnosed, the process of getting a diagnosis can be unclear and different for everyone, and not many support services are available for adults. More research on diagnosing adults with intellectual disability, differences between early and late-diagnosed adults, and support after diagnosis would be useful.
Keywords: adults; autism spectrum disorders; carers; diagnosis; gender; health services; psychiatric comorbidity.