Autism Spectrum Disorder (ASD) is a neurodevelopmental condition characterized by persistent difficulties in social communication and interaction, alongside restricted, repetitive patterns of behavior, interests, or activities. The presentation of ASD is highly variable, reflecting the concept of a spectrum. To capture this heterogeneity, the Diagnostic and Statistical Manual of Mental Disorders, 5th Edition (DSM-5), assigns severity levels based on the intensity of support an individual requires in daily life. This framework leads to questions about whether a person classified as Level 2 can transition to Level 1.
Defining Level 1 and Level 2 Support Needs
The DSM-5 classifies ASD into three severity levels, describing the current functional impact and the required intensity of aid. Level 1, designated as “Requiring Support,” applies to individuals who may have noticeable difficulty initiating social interactions and maintaining conversations. They may also show inflexibility of behavior that interferes significantly with functioning in one or more contexts, with difficulty switching between activities.
Level 2, or “Requiring Substantial Support,” is characterized by more pronounced symptoms across both core domains. Individuals at this level demonstrate marked deficits in verbal and nonverbal social communication skills, with social impairments apparent even when supports are present. Their restricted, repetitive behaviors interfere with functioning across various contexts, often involving distress or difficulty changing focus or action. The core difference lies in the degree of deficit and the substantial nature of the external support necessary for the individual to function.
Why Severity Levels Can Change Over Time
A severity level is not a fixed identity but a descriptor of an individual’s current functional capacity and the support they need at a specific point in time. Because the levels are based on observable behaviors and required support, they are inherently dynamic and subject to change. Evidence suggests that symptom severity can change substantially, with estimates of change ranging from 11% to 58%.
A transition from Level 2 to Level 1 is possible, typically occurring due to skill acquisition, maturation, and effective environmental adjustments. As a person develops new communication, social, and adaptive skills, their need for substantial external support decreases, which may warrant a formal re-assessment. This reclassification reflects an improved ability to manage symptoms and navigate the environment with less intensive aid. Cognitive ability, co-occurring conditions, and supportive environments also influence the potential for a change in the documented level.
Interventions That Support Functional Gains
Functional gains leading to a potential level change are often driven by early, intensive, and sustained intervention. Applied Behavior Analysis (ABA) is a widely recognized, evidence-based approach that focuses on modifying behaviors using positive reinforcement to improve social skills, communication, and adaptive functioning. Early Intensive Behavioral Intervention (EIBI), a form of ABA, has been associated with substantial gains in cognitive ability and adaptive behavior.
Speech and language therapy is essential for targeting deficits in social communication, enhancing both the understanding and use of language, including pragmatic social skills. For individuals with minimal verbal speech, Augmentative and Alternative Communication (AAC) methods, such as visual aids, are instrumental in developing functional communication. Occupational therapy addresses sensory processing difficulties and motor issues, focusing on enhancing daily living skills and independence. These interventions collectively target core deficits, teaching strategies that reduce the intensity of support required for daily life.
Understanding Improvement Versus Diagnostic Remission
It is important to distinguish between functional improvement and diagnostic remission in the context of ASD. A shift from Level 2 to Level 1 signifies a meaningful reduction in the intensity of support needed due to functional gains in communication and behavior management. However, this change does not mean the individual is “cured” or has “grown out” of the condition.
Autism Spectrum Disorder is considered a lifelong neurological condition; underlying differences in brain function persist even when symptoms are well-managed. While some individuals achieve what researchers term an “optimal outcome” and no longer meet the diagnostic criteria, the vast majority experience a reduction in severity rather than a complete loss of the diagnosis. The goal of intervention is to maximize functional independence and quality of life, understanding that the diagnosis itself remains, even if the required support level has decreased.