Researchers develop first autism symptom self-assessment for adults

Questionnaire measures repetitive and restricted behaviors; adults already diagnosed with autism invited to help evaluate test online

August 12, 2015

A new test may be one of the first effective self-assessments for a core symptom of autism in adults.

As described in the Journal of Autism and Developmental Disorders, the Adult Repetitive Behavior Questionnaire (RBQ-2) measures the extent to which adults are affected by repetitive and restricted behaviors. Restricted and repetitive behaviors make up one of the core symptoms of autism, alongside social and communication challenges.

"Many measures used for research and diagnoses of autism rely on parents, teachers or caregivers to report the behaviors of individuals with the condition," says study leader Sue Leekam, director of the Wales Autism Research Centre, at Cardiff University in the United Kingdom. "What our research has done is develop a test where individuals can report on their own behaviors.”

The challenge of adult diagnosis

Psychologists diagnose autism through direct observation and questionnaires that record the observations of parents and other caregivers. But the behavioral checklists they use are designed for assessing children, not adults – who often become adept at hiding their symptoms. In addition, parents of adults are frequently deceased or distant and, so, not available to fill out questionnaires about early childhood behaviors.

As a result, it’s difficult to find psychologists who feel qualified to evaluate adults for autism, and those who do tend to use their own untested methods.

Assessing repetitive and restricted behaviors

Repetitive and restricted behaviors include such habits and routines as lining up objects or arranging them in patterns, fiddling obsessively with objects or insisting that aspects of a daily routine remain exactly the same. The RBQ-2 test is designed to indicate when such behaviors are unusually frequent or severe.

To determine the test’s reliability, autism experts at Cardiff University and La Trobe University, in Melbourne, asked 311 British and Australian adults to complete the test. Around half had already been diagnosed with autism. The other half were not.

Though some adults without autism showed a high tendency for repetitive behaviors, those with an autism diagnosis scored significantly higher on the test.

Repetitive behaviors just one aspect

By itself, the test cannot diagnose autism. Repetitive and restricted behaviors are just one core symptom of autism – alongside social and communication challenges and, often, sensory issues. Repetitive behaviors are also associated with other conditions including obsessive-compulsive disorder, Parkinson's disease and Tourette syndrome.

Nonetheless, the new test represents an important advance, many experts agree.

“This new self-report measure is a great addition for adult health care, not just autism,” comments Kara Reagon, Autism Speaks associate director for dissemination science. “Adults wondering if they exhibit excessive restricted or repetitive behaviors now have a tool to help them determine if they do and then get help.”

“Too often people don’t realize that help is available for these types of behaviors,” Dr. Reagon adds. “Hopefully, by understanding their behavior and seeking help they will live happier, fuller lives.”

The investigators are now evaluating RBQ2 with more adults across the lifespan. If you’re 18 and older with a diagnosis of autism spectrum disorder (ASD), you are invited to participate by completing the test online.

Also see: Getting Evaluated for Autism as an Adult: Where to Go? Who to See?