Identifying as Autistic Without a Formal Diagnosis: Who Self-Identifies as Autistic and Why?

Background: Adults increasingly self-identify as autistic without a formal diagnosis, yet little research has systematically investigated (a) the unique characteristics, experiences, and needs of self-identifying adults and (b) their preferences regarding diagnosis. Understanding the unique needs and preferences of self-identifying adults is necessary to better support them. Method: We conducted a cross-sectional, mixed-methods study of U.S. autistic adults who either self-identified as autistic ( n = 147) or had a formal autism diagnosis ( n = 115), recruited via the survey platform Prolific. Participants were compared on (a) demographic characteristics, (b) autistic traits and experiences, (c) psychosocial outcomes, (d) support needs, and (e) beliefs about autism. Moreover, self-identifying participants reported whether they wanted a diagnosis, why or why not, and what barriers they faced. Results: Self-identifying autistic adults were similar to diagnosed adults in autistic traits, including diagnostic traits (>93% of both groups scored ≥14 on the Ritvo Autism and Asperger Diagnostic Scale-14 Screen). However, self-identifying autistic adults differed from diagnosed adults in significant ways. Self-identifying adults were more likely to be cisgender female (53.5% vs. 27.0%), experienced worse mental well-being ( d s = −0.41), were more likely to experience unmet support needs (71.4% vs. 47.0%), and faced unique barriers to receiving support (most frequently a lack of resources). The majority (68.7%) of self-identifying adults wanted a formal diagnosis but faced barriers in doing so. Self-identifying adults named a number of reasons for wanting a diagnosis (e.g., validation, access to certain services), but also grounds for hesitation (e.g., fear of stigma and discrimination). Conclusion: Adults who self-identify as autistic are similar to diagnosed adults in their autistic traits but face more barriers to accessing services and may be uniquely vulnerable to experiencing adverse psychosocial outcomes. Psychosocial outcomes in self-identifying autistic adults may be improved by increasing access to diagnosis and/or psychosocial services.