Abstract
<sec> <title>BACKGROUND</title> <p>The loss of the ability to communicate is consistently ranked as one of the 3 worst aspects of amyotrophic lateral sclerosis (ALS), a neurodegenerative disease of the upper and lower motor neurons of the brain and spinal cord that commonly results in impaired speech and loss of functional communication. Traditional single-stroke text entry can remain slow and effortful for people with advancing ALS, particularly when users must select letters individually to generate novel messages. Faster Output Through Simplified Text Entry and Response (FOSTER) is a novel text input program that combines a frequency-ranked word-generation algorithm with an eye-tracking–compatible interface to improve communication efficiency and reduce keystroke burden.</p> </sec> <sec> <title>OBJECTIVE</title> <p>The objective of this feasibility study is to evaluate the acceptability, usability, and preliminary effect of FOSTER compared with a control condition using traditional single-stroke eye-tracking text input among individuals with ALS.</p> </sec> <sec> <title>METHODS</title> <p>This prospective, single-center study is currently being conducted at the University of Vermont Medical Center ALS Clinic. Adults ≥ 18 years with a confirmed diagnosis of ALS who have sufficient ocular motility and visual acuity to operate an eye-tracking device are being recruited. Participants complete typing tests under two conditions in randomly assigned order: FOSTER-enabled text input and a control condition using traditional single-stroke eye-tracking text input. The primary preliminary effect outcome is mean typing time per prompt and feasibility outcomes include participant enrollment, calibration and task completion, and data capture reliability. Secondary outcomes include keystrokes per prompt, keystrokes per word, message efficiency, participant-reported usability and satisfaction, qualitative feedback, clinician-reported usability, and error-related outcomes. Paired within-participant comparisons will be used to evaluate differences in typing time between conditions, and descriptive analyses will be used for feasibility and exploratory outcomes.</p> </sec> <sec> <title>RESULTS</title> <p>Recruitment began in April 2026. As of July 2026, 2 participants have been enrolled. Data collection is expected to be completed in fall 2026, with analysis and dissemination of feasibility, usability, and preliminary effect results expected in winter 2026.</p> </sec> <sec> <title>CONCLUSIONS</title> <p>This protocol describes a feasibility study evaluating the acceptability, usability, and preliminary effect of a frequency-ranked text input program designed to improve communication efficiency and reduce keystroke burden during eye-tracking communication for individuals with ALS. The study findings will inform future refinement of FOSTER and guide forthcoming clinical trials assessing assistive communication programs and technologies for individuals with progressive motor and communication impairment.</p> </sec>