Therapy decision guide · Evidence status: Emerging

Sensory Integration Therapy: What It Is and What the Evidence Shows

Developed by occupational therapist Jean Ayres, SI therapy uses structured sensory activities to help regulate how the nervous system processes input. Here is what it involves, what the research does and does not support, and what to ask before starting.

In brief

In short

  • Delivered by occupational therapists trained specifically in the Ayres Sensory Integration (ASI) framework, not general pediatric OT experience
  • Considered when sensory processing differences interfere with daily participation at home, school, or in the community
  • Evidence is strongest for sensory and motor outcomes; weaker and more mixed for behaviour and social outcomes
  • Not a stand-alone substitute for core developmental, communication, or behavioural supports

General information only, not a diagnosis, treatment plan, crisis service, or individual estimate. Confirm your next step with the linked source or a qualified professional.

Functional goal

For children whose sensory processing gets in the way of daily life.

SI therapy is considered when a child is under- or over-responsive to sound, touch, movement, or other sensory input in ways that interfere with participation at home, school, or in the community, not simply because a child has sensory preferences.

What it is

Ayres Sensory Integration (ASI) is an occupational therapy approach developed by A. Jean Ayres, an OT and neuroscientist, in the 1960s and 1970s. Ayres proposed that many children with learning and developmental challenges, including autism, had underlying difficulties in how their brains organized and interpreted sensory information. Her Sensory Integration and the Child (1979) remains foundational to the field.

ASI uses child-directed, play-based activities involving specific sensory equipment to challenge and support the nervous system’s ability to process input. It follows the child’s lead and the “just right challenge” principle, sensory experiences slightly beyond the child’s current comfort zone, in a safe, supportive environment.

Evidence and effectiveness

SI therapy is emerging, not yet consensus-level evidence-based.

The evidence base has grown since the development of the ASI Fidelity Measure (ASI-FM) by Parham and colleagues, which lets researchers check treatment integrity across studies. A 2019 randomized controlled trial (Schaaf et al.) found significant improvements in goal attainment and daily living skills for autistic children receiving fidelity-based ASI compared to usual care, and a 2020 Cochrane-adjacent review found meaningful improvements in goal attainment. Systematic reviews show moderate evidence for sensory and motor outcomes; evidence for social and behavioural outcomes is more limited and mixed. ASI appears on the list of evidence-based practices for autism in several international guidelines, though strength-of-evidence ratings vary by outcome.

This label applies specifically to structured ASI delivered by a trained therapist following the fidelity framework, not to general “sensory activities” that use similar equipment without adhering to it.

Evidence status

Evidence-based

Emerging

Some quality studies show benefit, but evidence is limited or mixed.

Unproven / unsafe

Classified as emerging: credible RCT and systematic-review support exists for sensory and motor outcomes when delivered with fidelity, but the evidence base is smaller and more mixed than for established therapies, and does not extend uniformly to social or behavioural outcomes.

What a session may involve

Inside a fidelity-based ASI session.

A fidelity-based ASI session requires a purpose-built sensory gym equipped with:

  • Suspended equipment, platform swings, net swings, bolster swings, for vestibular and proprioceptive input
  • Crash pads and foam pits for deep pressure and proprioceptive input
  • Tactile bins, textured surfaces, and materials for tactile exploration
  • Climbing walls, scooter boards, and obstacle courses for motor planning
  • Lycra tunnels, weighted tools, and resistance equipment

The OT observes the child’s responses to sensory input and adjusts the activity in real time. Session length and frequency vary; ask how the therapist will explain the goal, monitor response, and review the plan.

Alongside direct therapy, trained OTs often provide a sensory diet, a schedule of targeted sensory activities through the day (e.g. 10 minutes of heavy work before homework), to extend session benefits into daily routines.

Who delivers it, and credentials to check

Not all OTs are trained in Ayres Sensory Integration. General pediatric OT experience is not the same credential.

  • Confirm the OT is registered with the College of Occupational Therapists of Ontario (COTO).
  • Ask whether they hold specific Ayres Sensory Integration (ASI) training, e.g. certification through the USC Chan Division (the Ayres Clinic) or the CLASI certificate program, not just general pediatric OT experience.
  • Ask whether they use the ASI Fidelity Measure (ASI-FM) to guide and check their practice.
  • Ask what a typical session structure looks like and whether they track goal attainment over time.

Cost, funding, and access in Ontario

Children’s Treatment Centres (CTCs) in Ontario often have OTs trained in ASI. Privately, autism-specialized OT clinics in urban centres frequently offer ASI, and some services are fundable through OAP Core Clinical Services or interim one-time funding.

See what OAP funding covers before booking, funding eligibility and coverage limits vary by budget category and change over time.

Questions to ask before starting

  • What functional goal are we targeting, and how will we know if it is working?
  • Are you using fidelity-based Ayres Sensory Integration, or general sensory activities that borrow the same equipment?
  • How many sessions before we should expect to see a measurable change?
  • Is this covered or fundable through OAP funding, and what will it cost if not?

Limitations and what this therapy can’t promise

  • Evidence is strongest for sensory and motor outcomes, weaker and more mixed for behaviour and social outcomes.
  • Benefits found in fidelity-based ASI research do not automatically apply to informal "sensory play" that skips the ASI framework.
  • SI therapy is not a stand-alone substitute for core developmental, communication, or behavioural supports, it is typically used alongside them.
  • Results vary by child; no therapy, including SI therapy, can promise a specific outcome or cure.

Frequently asked questions

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Citable facts from this page(2)

What does the WHO say about early autism intervention timing?

Verified

The WHO Fact Sheet on Autism Spectrum Disorders (updated Sept. 17, 2025) states that timely access to early evidence-based psychosocial interventions can improve the ability of autistic children to communicate effectively and interact socially. Dawson et al. (2010, Pediatrics; PMID 19948568) confirmed in an RCT that ESDM (Early Start Denver Model) at 18–30 months produced significant developmental gains.

Source: WHO Fact Sheet: Autism Spectrum Disorders (updated Sept. 17, 2025); Dawson et al., Pediatrics 2010 (PMID 19948568) · Open source record

What official government data tracks the Ontario autism waitlist?

Verified

The current province-wide waitlist record is the MCCSS FOI data published through the Ontario Autism Coalition data hub. As of May 2026, it shows 91,974 registered children and 22.5% with active funding agreements. Historical FAO, Auditor General, OHRC, and AccessOAP records provide separate context and should be cited for their own claims.

Source: MCCSS FOI via OAC May 2026 · Open source record

Sources on this page

The source chain stays visible.

Key claims are paired with their source, evidence tier, and verification date so readers can inspect the public record directly.

Facts3
Sources3

Early Start Denver Model (ESDM) delivered to children aged 18–30 months produced significant gains in IQ, adaptive behaviour, and autism severity — some children no longer met diagnostic criteria at follow-up

Primary sourceDawson G, Rogers S, Munson J, et al. (2010)Verified 2010-01-01

Cochrane systematic review finds evidence that early intensive behavioural intervention (EIBI) may produce positive effects on adaptive behaviour and communication for young children with ASD (low certainty of evidence)

Primary sourceReichow B, Hume K, Barton EE, Boyd BA (2018)Verified 2018-05-09

WHO recommends accessible, community-based early interventions for children with autism. Timely evidence-based psychosocial interventions improve communication and social engagement

Primary sourceWorld Health Organization (2025)Verified 2025-09-17
Last system verification: 2026-08-10. Next scheduled update: 2026-11-05.
View methodologyBrowse every source

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Parent of autistic child navigating OAP system