Guidelines to Assist in Autism Diagnostic Assessments with Females: A Delphi Study

Purpose: While growing evidence highlights the challenges faced by autistic females during diagnostic assessments, it remains unclear how well this research is applied in clinical practice. This study aimed to gather consensus among clinicians on recommendations for autism assessments to improve diagnostic validity for cis-gendered females. Method: A three-round Delphi study was conducted with registered healthcare professionals experienced in conducting autism diagnostic assessments with females. Results: Thematic analysis of Round 1 responses identified five themes: Attributes of the Assessor, Post-Clinical Qualification Education and Learning, Diagnostic Tools, Questions Asked, and Sources of Information. These themes produced 28 statements evaluated in Rounds 2 and 3. Eighteen reached 80% consensus in the final round. Experts emphasized the important of assessors having strong knowledge of research into autism in women, co-occurring conditions, other developmental conditions, and masking. Ongoing professional development on autism in women was considered essential and it was recommended that new assessors shadow female assessments. Experts agreed the ADOS-2 is not always useful for females, whereas screening tools can provide valuable narrative insights, though these need to be interpreted carefully due to potential male bias. Experts supported including more prompts to explore subtle differences in social communication and repetitive patterns of behaviour and stressed the importance of masking behaviours and experiences across different relationships. Masking should also be considered when interpreting informant information. Conclusions: Findings reveal inconsistencies in how clinicians consider sex-related factors in autism assessments, highlighting the need for formal guidance. The next steps will be to develop this guidance, incorporating research evidence, the perspectives of autistic women and girls, and Delphi results. This aims to improve the experience, and accuracy of diagnosis for girls and women undergoing autism assessment, increasing consistency across services, and supporting clinicians.