Autism Diagnostic Observation Schedule (ADOS) scores in males and females diagnosed with autism: a naturalistic study

Many tools are available for assessing autism in an adult population; however, few have been studied for the effects of gender on diagnostic scores. The purpose of this paper is to evaluate the Autism Diagnostic Observation Schedule (ADOS) assessment for gender bias in a clinical population, specifically whether the ADOS favours a “male-type” of autism.

The ADOS scores of patients referred to an NHS specialist autism assessment service were retrospectively examined for significant gender differences. The combined ADOS scores and diagnostic outcome were grouped by gender for each participant. The data were analysed in SPSS using independent t-tests to look for significant gender differences between combined ADOS scores and diagnostic outcomes.

A significant difference was observed in the mean combined ADOS scores for those participants who later received an autism diagnosis (male=10, female=6, t (13)=3.34, p=10; 0.005). However, no significant difference was observed between mean scores of those who did not receive an autism diagnosis (t (26)=1.21, p=0.237).

The ADOS is a popular assessment used for autism diagnosis. These results provide support for a male gender bias. This could have clinical implications for autism assessment services, whereby lower diagnostic thresholds could be considered for female patients. This could allow more females with autism to receive a diagnosis, and access support services.