Diagnostic Gap

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The gap between IQ and adaptive functioning in autism spectrum disorder: Disentangling diagnostic and sex differences (2022)

Authors: Goldie A. McQuaid, Kevin A. Pelphrey, Susan Y. Bookheimer, Mirella Dapretto, Sara J. Webb, Raphael A. Bernier, James C. McPartland, John D. Van Horn, Gregory L. Wallace, and GENDAAR Consortium

Summary:

This study explores how children with autism spectrum disorder (ASD) often have a significant gap between their IQ and they handle daily tasks and challenges. A phrase to describe how people deal with tasks and challenges is adaptive functioning. Adaptive functioning includes skills needed for daily living, communication, and socialization. This research included 177 children with ASD and 178 children without ASD between the ages of 8 and 17. The researchers asked the children questions and assessed them using an adaptive functioning level scale and an IQ scale. The study found that this gap exists more in children with ASD compared to children without ASD and that this gap increases with age. It also showed that while both males and females with ASD have fewer adaptive skills, the gap between IQ and adaptive functioning is found more in males. The study shows how important it is to consider both diagnostic and sex differences when assessing adaptive functioning in children with ASD.

Do Biological Sex and Early Developmental Milestones Predict the Age of First Concerns and Eventual Diagnosis in Autism Spectrum Disorder? (2020)

Authors: Clare Harrop, Erin Libsack, Raphael Bernier, Mirella Dapretto, Allison Jack, James C McPartland, John D Van Horn, Sara J Webb, Kevin Pelphrey, and GENDAAR Consortium

Summary:

Currently, the average age people receive an autism diagnosis is 4 years old. This age is often later in females. There are usually differences between males and females in how autism develops early in life. The goal of this study was to explore these differences and understand how they are related to how old someone is when they are diagnosed with autism. The results of the study showed that even though females usually get an autism diagnosis later, just being female or male does not predict the age of diagnosis. However, sex and language development significantly impact the age that autistic traits are noticed. The study also showed that parents reported that females learned language faster than males. It also showed that parents observed autistic traits later for females compared to males. This study shows the importance of considering both biology and behavior in diagnosing autism early.

Preliminary Validation and Feasibility of the Autism Detection in Early Childhood-Virtual (ADEC-V) for Autism Telehealth Evaluations in a Hospital Setting (2022)

Authors: Elizabeth M Kryszak, Charles M Albright, Kevin G Stephenson, Rose E Nevill, Darren Hedley, Claire O Burns, Robyn L Young, Eric M Butter, Kerrigan Vargo, and James A Mulick

Summary:

The COVID-19 pandemic highlighted the need to be able to correctly diagnose autism spectrum disorder (ASD) online through telehealth. Researchers tested a new online test called the Autism Detection in Early Childhood-Virtual (ADEC-V). They did this to see how good it was at diagnosing children with ASD. The researchers chose the ADEC-V because it is short, easy to use online, and simple for parents to do from home. The study included 121 children who were 18-47 months years old. The results showed that the ADEC-V diagnosed autism correctly and can be a really good tool for diagnosing ASD. Researchers encourage others to study the ADEC-V in the future with more children (with and without ASD).

Who, When, Where, and Why: A systematic review of “late diagnosis” in autism

Authors: Alison S Russell*, Tyler C McFayden*, Margaret McAllister, Kimberly Liles, Sophie Bittner, John F Strang, Clare Harrop

Summary:

This study systematically reviewed 420 research articles on late diagnosis of autism. The articles were published around the world, between 1989-2024. The authors’ goal was to understand how researchers describe a “late diagnosis” of autism and how they decide whether a diagnosis is early, on time, or late. They found that the definition of a “late diagnosis” of autism has changed over time and differs between people and places. The authors recommended including community members’ ideas in future research and also studying how age of diagnosis affects people's quality of life. They also suggested using a flexible definition of “late diagnosis" that reflects the specific community and needs that are being studied.

Borderline Personality as a Factor in Late, Missed, and Mis-Diagnosis in Autistic Girls and Women: A Conceptual Analysis (2024)

Authors: Goldie A. McQuaid, John F. Strang, and Allison Jack

Summary:

Autism without intellectual disability is often diagnosed later and with more difficulty in girls and women compared to boys and men. Autistic girls and women are frequently misdiagnosed, with borderline personality disorder (BPD) being a common misdiagnosis. This review looks the differences between BPD and autism in girls and women, focusing on traits that may lead to confusion between the two. It highlights the need to carefully examine an individual's symptoms to differentiate between autism and BPD accurately. Understanding these differences is important for providing the right treatment and support.