The Russian version of the Oxford Cognitive Screen: validation with stroke survivors

Abstract

Introduction: We present the adaptation of the Oxford Cognitive Screen into Russian (Rus-OCS). The Rus-OCS measures attention, memory, praxis, language and number processing and generates a unique cognitive profile. Rus-OCS is designed to detect cognitive impairment using nonverbal responses and is suitable when aphasia is present (see Kuzmina et al., 2016, 2017). Study aims and hypotheses: The present study has two goals: (1) to establish the concurrent validity and the reliability of the Rus-OCS; and (2) to compare performance of seniors on the Rus-OCS. The hypothesis is that Rus-OCS will show good reliablity and convergent validity. Method: The Rus-OCS was administered to 79 stroke patients and 42 neurologically healthy adults aged between 18 and 91 years. Convergent validity of the Rus-OCS was established via correlations with subscales from the Montreal Cognitive Assessment (MOCA), Star Cancellation Test and the Lurian Neuropsychological Battery. Validity data from the clinical sample were complemented with neuropsychological notes. Control participants were invited to participate in an alternative version of the Rus-OCS several days after the first assessment. Results: Pearson correlation coefficients (p<.01) with established tests varied from moderate (0.30-0.49) to high (0.50-1.00). Wilcoxon signed rank tests found no significant differences between test and retest scores on any subtest (p<.01). Cronbach’s alpha (α) coefficients for internal consistency ranged from good α = 0.74 to excellent α = 0.91 (Cronbach, 1951). Kruskal-Wallis tests revealed significant differences (p<.05) in performance for the stroke and control samples on all Rus-OCS subtests except for a measure of space asymmetry called the Hearts test. Preliminary normative data are summarised for the control group in Table 1. Conclusion: The Rus-OCS is reliable, valid and suitable for Russian speakers. Convergent validity, test-retest reliability, internal consistency, and discriminative power are established. However, demographic constraints must be considered for valid clinical interpretation. Given the lack of quantitative neuropsychological scales for Russian speaking aphasia patients, the impact of the Rus-OCS for diagnosis and post-stroke rehabilitation is significant. Rus-OCS is therefore recommended for more research with Russian-speaking stroke patients with aphasia. The results complement similar research with the OCS in Cantonese (Kong, et al., 2015; Lam et al., 2014) and show non-verbal cognitive assessment is reliable and valid for individuals with aphasia.