ABCD SW: Autistic Behavior & Computer-based Didactic Software
M. Claudia Buzzi, Marina Buzzi, Davide Gazzè, Caterina Senette, Maurizio Tesconi · 2012 · Proceedings of the International Cross-Disciplinary Conference on Web Accessibility (W4A) · doi:10.1145/2207016.2207037
Summary
This demo paper from IIT-CNR in Pisa presents ABCD SW, an open-source web application designed to support Applied Behavior Analysis (ABA) intervention with low-functioning autistic children. The software implements Discrete Trial Training (DTT) — a structured teaching method where skills are broken into small components and taught through repeated trials with reinforcement — combined with Augmentative and Alternative Communication (AAC) principles. The system uses a distributed two-device architecture: a tutor controls the session from a laptop, setting up exercises and recording data, while the child interacts with trials on a separate tablet with a simplified, distraction-free touchscreen interface. The devices synchronise in real time via a shared database using Ajax polling every second. The software adapts content based on the child's profile — presenting words for non-receptive children and word choices for non-verbal children in expressive trials — and allows tutors to select appropriate reinforcements (rewards) for each child. Built on Drupal CMS with PHP, AJAX, HTML5, and SVG graphics via the Raphaël JavaScript library.
Key findings
The distributed architecture solved several practical problems encountered during development. An early version using a large horizontal touchscreen to simulate a table surface suffered from touch sensitivity issues that caused dragged objects to be lost — a critical failure for autistic children who require rapid and unambiguous feedback. Tablets (iPad and Android) proved more reliable for drag-and-touch interactions and had the added benefit of being wireless (children were observed unplugging cables from connected displays). The real-time synchronisation between tutor and child devices freed the tutor from having to memorise trial data, allowing them to focus cognitive resources on the intervention itself and the child's behaviour. The tutor control panel tracked prompt levels (0-100%), child behaviours (errors, non-collaboration, self-stimulation), tutor errors, and provided running statistics on correct responses, prompts, and errors. The system was being piloted with 7 children at the time of publication. The web-based approach using a CMS enabled multilingual support, content management by non-technical users, and anywhere/anytime access.
Relevance
ABCD SW demonstrates how accessibility extends beyond traditional web content concerns into specialised educational and therapeutic contexts. The design decisions — separate simplified interfaces for different user types, adaptive content based on ability profiles, reliable touch interaction with immediate feedback, distraction-free environments — reflect deep understanding of the sensory and cognitive needs of autistic children. For accessibility practitioners, this project illustrates several transferable principles: the importance of matching interaction modality to user capability (touchscreen over mouse for fine motor challenges), the value of separating complex control interfaces from simplified user-facing interfaces, and how real-time device synchronisation can redistribute cognitive load between users. The open-source, web-based approach also makes the tool more accessible to under-resourced schools and therapy centres than proprietary alternatives.
Tags: autism · cognitive accessibility · augmentative and alternative communication · educational technology · assistive technology · touchscreen accessibility · adaptive interfaces
Standards referenced: HTML5