ESJ Featured Article of the Month – August 2025

The Mini-Oxford Cognitive Screen – A Very Brief Cognitive Screen for Use in Chronic Stroke

Cognitive impairment is common after stroke, affecting 30-50% of stroke survivors.¹ Few validated tools exist to assess cognition after stroke. Commonly used tools like MoCA (Montreal Cognitive Assessment) were designed for dementia. Post-stroke cognitive deficits differ from dementia. Key domains which may be affected by stroke, for example neglect, apraxia, reading, and writing could be missed by dementia screening tests. Furthermore, MoCA relies on intact verbal skills and expressive language. Stroke patients with residual language impairments may score poorly on MoCA- appearing to have memory impairment when they actually have language impairment. The Oxford Cognitive Screen (OCS) was developed as a screening tool to detect cognitive deficits after stroke. It was designed for use acutely after stroke and focuses on neglect, apraxia, reading and writing and can be adapted for patients with aphasia. However, it takes approximately 20 minutes to administer, this timeframe maybe prohibitive for primary care physicians. In this month’s issue of European Stroke Journal, Webb and colleagues describe a new cognitive screen, the Mini-OCS, a brief 8-minute post-stroke cognitive screening tool, designed for use in chronic stroke survivors by primary care physicians.²

Firstly, Webb and team developed the Mini-OCS based on the full OCS with the goal of assessing all cognitive domains which may be affected by stroke including language, memory, attention, praxis, numerical processing and executive function, but condensing them into a tool which could be administered in less than 10 minutes. Next, they recruited two test populations: 164 healthy controls and 89 chronic stroke survivors. All were community dwelling and at least 6 months had passed since their stroke. All participants were able to concentrate for 20 minutes and provide informed consent. All participants were tested with a comprehensive battery of tests including MoCA, OCS, the Comprehensive Aphasia Test (CAT) number multiple-choice calculations, the Boston Diagnostic Aphasia Examination pretend objects and 10 sentence reading subtasks, the Cognitive Linguistic Quick Test symbol trails, and the Behavioral Inattention Test star cancellation test, along with the newly derived Mini-OCS.

Healthy controls and stroke survivors were of similar ages (mean 68.6 years and 69.8 years respectively) and had on average between 14-15 years of education. For stroke patients, the median NIHSS score was 6.5, indicating mild to moderate severity stroke. Approximately a third had no significant post-stroke disability (represented by a mRS of 0-1), over half had mild to moderate disability (mRS 2-3), and one in eight had severe disability (mRS 4 or 5). By contrast, the vast majority (95%) of healthy controls had no disability (mRS 0).

It took people in the healthy control group on average 7.3 minutes (±SD 1.63, range 4-13) to complete the Mini-OCS, and only slightly longer (8.7minutes ±SD 2.63) for patients with prior stroke, indicating that the investigators achieved their goal of designing a score which could feasibly be performed in under 10 minutes.  Scores from specific Mini-OCS domains were compared to the corresponding domains in the reference cognitive tests. Each domain correlated appropriately indicating that Mini-OCS was a valid screening tool and performed comparably to those reference cognitive tests.

The investigators then defined normal values for the Mini-OCS based on the healthy control cohort. They found that age had an effect on these cut-offs and have provided age-adjusted normal value cut-offs in a table in this paper. Finally, the investigators compared differences in Mini-OCS performance between the healthy control group and the chronic stroke group. In this cohort, 7.9% of chronic stroke survivors had evidence of cognitive impairment using the Mini-OCS. This varied across domains with only 2.8% showing impairment in number calculations but 10.3% had impairment in executive function. The Mini-OCS was able to differentiate stroke survivors from control participants.

This study describes a new brief cognitive screening tool – the Mini-OCS -specifically for use in survivors of stroke. The test can be administered in less than 10 minutes and it assess a range of cognitive domains which may be affected by stroke. In this way, the Mini-OCS meets a need in stroke care for a brief screening test which can be quickly administered in primary care or outpatient clinic, which will allow clinicians to screen cognitive function after stroke and identify patients who require more detailed cognitive testing or neuropsychological assessment. The Mini-OCS can be found at https://www.ocs-test.org/ and a license can be obtained free of charge for publicly funded research or free/public clinical services. Further validation studies and assessments of feasibility of the implementation of Mini-OCS in routine stroke care are now needed.

The mini-Oxford Cognitive screen- a very brief cognitive screen for use in chronic stroke

Webb et al.

Online first 27 July 2025

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1. Pendlebury ST, Rothwell PM. Incidence and prevalence of dementia associated with transient ischaemic attack and stroke: analysis of the population-based Oxford Vascular Study. Lancet Neurol 2019; 18(3): 248-58.
2. Webb SS, Sun L, Tang EYH, Demeyere N. The mini-Oxford cognitive screen (Mini-OCS): A very brief cognitive screen for use in chronic stroke. European Stroke Journal; 0(0): 23969873251358811.