An ASHA EBP crosswalk.

ASHA defines evidence-based practice as the integration of three sources of knowledge: the best available external research evidence, the clinician's expertise, and the values and preferences of the individual and family. The framework is meant to be applied as an integration, not as a hierarchy in which the first pillar trumps the other two.

Applied honestly to Assisted Communication (AC) — the umbrella term used in the contemporary literature for S2C, RPM, the Spellers Method, supported typing, and FC — the crosswalk looks like this. A note on framing: ASHA's position statement treats all AC approaches as if they were the same thing. They are not, and the evidence base differs across them. Reading the pillars below with that in mind matters.

Pillar 1 — Best available external evidence

The most-cited critiques rely on a small body of older message-passing studies and on professional position statements that draw on them. Both are part of the evidence base. Neither is the whole of it.

The contemporary evidence base also includes:

• Eye-tracking work documenting target-anticipatory gaze.
• A large motor-planning literature on praxis differences in autism.
• Outcomes data from adult nonspeaking communicators.
• The principles-of-motor-learning literature that responsible practice now draws on.
• First-person testimony from nonspeaking authors, which is data even when it is not a controlled trial.

EBP requires the best available evidence, not only the evidence that confirms a prior position. A clinician who has read Jaswal et al. (2020), the motor-planning literature, and the position statements is doing the work of EBP. A clinician who has only read the position statements is not.

Pillar 2 — Clinical expertise

The clinicians with the most direct experience of motor-based supported communication — SLPs and OTs who have worked with these learners over years — are systematically under-represented in the published critique literature. Their expertise is not the same as peer-reviewed evidence, but it is not nothing either, and the EBP framework explicitly asks for it.

The exclusion of practitioner expertise from "the evidence" — when that expertise is uncomfortable for a prior position — is itself a methodological choice that the framework was designed to resist.

Pillar 3 — Client and family values

This is the pillar that the conventional critique most often skips entirely. Nonspeaking communicators and their families have unambiguous, repeatedly stated values: access to a method that lets the communicator be heard, presumption of competence, and the opportunity to fail safely on the way to fluency.

A position statement that overrides this pillar — that effectively tells a family they may not use the only method through which their child has produced text — is not practicing the EBP framework it cites. It is using one pillar to silence the other two.

What integration actually looks like

Integrated EBP in this context looks like a clinician who:

• Has read the older critiques and the newer literature.
• Brings their own clinical experience to bear without pretending it is irrelevant.
• Engages the family's values explicitly and respectfully.
• Documents outcomes, builds fading into the plan, and stays curious about authorship without treating it as settled in either direction.
• Coordinates rather than competes with the family's existing AAC and motor supports.

One more thing

EBP was designed to protect patients from clinicians who would substitute personal preference for evidence. It was not designed to protect institutions from updating their position when the evidence moves. Both failure modes are real. The current conversation about supported communication has more of the second than of the first.