Understanding the Diagnostic Process of Autism Spectrum Disorder in Females: The Role of Initial Diagnosis and Comorbidities

Background: To ensure early intervention, it is important that children with autism spectrum disorder (ASD) receive a diagnosis as early as possible, as identifying and diagnosing ASD early can improve an individual’s quality of life and reduce social, emotional, and behavioural problems (Bargiela, Steward, & Mandy, 2016). ASD can be diagnosed as young as two years of age; however, there are many children that do not receive a diagnosis until school age, defined here as five years of age and older (Pringle et al., 2012; Hiller, Young, & Weber, 2015). It has been suggested that the heterogeneity of symptoms and the presence of comorbid mental and physical health disorders can contribute to a late diagnosis (McMorris et al., 2013). Sex also contributes to late diagnosis, as females typically receive a diagnosis later than males (Duvekot et al., 2017; Hiller, Young, & Weber, 2016). Inconsistencies in the current literature have lead to equivocal conclusions related to the role of sex in children receiving a late diagnosis of ASD. Thus, it is unclear if females experience more instability in their diagnostic process than males.

Objectives: Given the inconsistencies in the existing literature, the primary objective of this study is to determine how sex impacts the diagnostic process of females with ASD. In particular, the study will first investigate if females, compared to males, have more instability in their diagnostic process, as indicated by a) taking longer to receive their ASD diagnosis; and b) receiving numerous initial diagnoses prior to their ASD diagnosis. A secondary aim of the study is to determine whether the existence of co-occurring mental health disorders may impact these sex differences in the diagnostic process.

Methods: Caregivers of children 18 years of age or younger, and who have a primary diagnosis of ASD are asked to complete a questionnaire that collects information about: 1) demographic information (i.e. age and sex); 2) initial diagnosis; and 3) multiple diagnoses and comorbid psychiatric or health conditions. Participants are recruited through: 1) autism-specific community agencies in Calgary, Alberta, who support children; 2) the University of Calgary external research page; 3) Facebook ASD support groups; and 4) the ASD Diagnostic Clinic at Alberta Health Services.

Results: We currently have 18 male and 14 female participants, and anticipate 35 males and 35 females by Spring 2019. Descriptive statistics will be conducted for all variables, including frequencies, means, standard deviations, and ranges. To answer the aforementioned research questions/aims, multiple regression models will be used.

Conclusions: Understanding whether sex impacts the process of receiving an ASD diagnosis can inform diagnostic tools for clinicians to determine early signs for diagnosis, particularly in females. The importance of determining sex differences in the first diagnosis a child receives can provide information as to whether clinicians are misdiagnosing females at a higher rate than males. These findings will aid health practitioners in their awareness of early ASD symptoms in both sexes, developing community outreach and intervention programs, and ultimately improve outcomes for these children and their families.