SPACEY for ADHD in Primary Schools: Study-Protocol for a Randomised Waitlist-Controlled Trial with an Embedded Randomised Single-Case AB Design

SPACEY-ADHD is a school-based intervention study evaluating the effectiveness and feasibility of SPACEY, a low-threshold “room-within-a-room” classroom arrangement designed to reduce distracting stimuli, enable structured withdrawal, and support attention and self-regulation in pupils with ADHD. The project addresses the need for pragmatic, scalable supports that can be implemented in everyday teaching to improve engagement and reduce ADHD-related classroom difficulties. We will recruit N = 40 pupils from 2–3 primary schools. Twenty pupils have a documented ADHD diagnosis; a further twenty will be identified through elevated scores on the SDQ Hyperactivity scale in a class-wide screening. Pupils will be randomised to SPACEY or a waitlist control (n = 20 per condition). The group component follows a randomised pre–post design over approximately three months, with the waitlist group receiving SPACEY after post-test. Within the SPACEY condition, we additionally implement a controlled single-case AB design comprising a three-week baseline (A) and a 3–4-week intervention phase (B); the onset of phase B is randomised across pupils. Daily Direct Behaviour Ratings (DBR) will capture on-task behaviour, concentration, and impulse control. ADHD-related difficulties will be assessed pre–post using the SDQ. Implementation quality will be documented via a brief fidelity checklist. Analyses will integrate (a) group-level comparisons of pre–post change and (b) single-case visual analysis with non-overlap indices (e.g., NAP) and aggregated estimates across cases. Expected outcomes are improved academic engagement and self-regulation and reduced ADHD-related difficulties, yielding practice-relevant evidence and effect-size estimates for planning a larger confirmatory trial.