Objectives Spatial neglect, a debilitating cognitive syndrome and predictor of poor functional outcome, affects attention and awareness after stroke. Early rehabilitation is essential but neglect itself may impede participation in therapy. In a proof-of-concept study nested within an RCT, we investigated whether the oft-reported immediate effects of prism adaptation training (PAT) might enable engagement if introduced at the start of an occupational therapy session. Methods Early after stroke we video-recorded in-patients carrying out a standardised activity in their first RCT occupational therapy session, before and after PAT (or a control therapy activity). Level of engagement was later scored by a video-rater, experienced in therapy, blind to arm allocation (intervention/control) and whether randomly presented videos were recorded pre- or post-therapy. The rater recorded engagement scores on a 100mm visual analogue scale. Treating therapists also reported, on a 3-point Likert scale, whether or not engagement changed. Results 49 of the RCT's 53 patients were recruited (37 PAT, 12 control), 43 of whom consented to be video-recorded. Regression analysis did not suggest improvement in engagement following one session of PAT, using the blinded expert video scoring method: mean difference (95% CI) = -0.5 (-7.4 to 6.4) mm; p=0.89). Similarly, post-hoc re-rating of engagement scores (the video-rater viewed paired pre- and post-therapy recordings but remained blind to arm allocation) excluded any material difference in engagement following PAT: mean difference (95% CI) = 1.2 (-2.5 to 4.9) mm; p=.52). Impressions of level of engagement provided by the treating occupational therapists also suggested no change: OR (95% CI) = 1.3 (0.13 to 13); p=0.81). Conclusions Despite the need to enable neglect patients to engage in the therapy they are offered, we are confident that a single session of PAT at the start of a therapy session does not enhance immediate engagement in occupational therapy early after stroke. Our study does not address the alternative definition of engagement as a longitudinal, rapport-building process which could meaningfully be explored. Keywords Spatial neglect; inattention; rehabilitation; engagement; therapy; stroke

Dysarthria after stroke is when speech intelligibility is impaired, and this occurs in half of all stroke survivors. Dysarthria often leads to social isolation, poor psychological well-being and can prevent return to work and social lives. Currently, a variety of outcome measures are used in clinical research and practice when monitoring recovery for people who have dysarthria. When research studies use different measures, it is impossible to compare results from trials and delays our understanding of effective clinical treatments. The aim of this study is to develop a core outcome set (COS) to agree what aspects of speech recovery should be measured for dysarthria after stroke (COS-Speech) in research and clinical practice. The COS-Speech study will include five steps: (1) development of a long list of possible outcome domains of speech that should be measured to guide the survey; (2) recruitment to the COS-Speech study of three key stakeholder groups in the UK and Australia: stroke survivors, communication researchers and speech and language therapists/pathologists; (3) two rounds of the Delphi survey process; (4) a consensus meeting to agree the speech outcomes to be measured and a follow-up consensus meeting to match existing instruments/measures (from parallel systematic review) to the agreed COS-Speech; (5) dissemination of COS-Speech. There is currently no COS for dysarthria after stroke for research trials or clinical practice. The findings from this research study will be a minimum COS, for use in all dysarthria research studies and clinical practice looking at post-stroke recovery of speech. These findings will be widely disseminated using professional and patient networks, research and clinical forums as well as using a variety of academic papers, videos, accessible writing such as blogs and links on social media. COS-Speech is registered with the Core Outcome Measures in Effectiveness Trials (COMET) database, October 2021 https://www.comet-initiative.org/Studies/Details/1959 . In addition, “A systematic review of the psychometric properties and clinical utility of instruments measuring dysarthria after stroke” will inform the consensus meeting to match measures to COS-Speech. The protocol for the systematic reviews registered with the International Prospective Register of Systematic Reviews. PROSPERO registration number: CRD42022302998 .