The objective of this study was to begin to assess the difficulty level of items from the two alternate MoCA versions in relation to their corresponding content items from the original MoCA (Version 1). We hypothesized that inadequate matching of the difficulty of questions in the alternate MoCA tests could explain in part the low sensitivity to change in cognitive ability over time that was recently reported for alternate MoCA versions. Although the problem could be solved by establishing separate cut-offs with comparable sensitivity/specificity for each of the MoCA test forms, high inter-form reliability is ensured by selecting alternate items that are matched to the original items by their difficulty. Any differences in difficulty level between the new and original items would lead to discrepancies in screening properties among the parallel forms, affecting the inter-form reliability that is a prerequisite for monitoring cognitive changes longitudinally. To be interchangeable with the original MoCA, items from alternate versions of the MoCA must be of comparable difficulty to their content-matched originals. ( 6) The results of that analysis showed that items with equal scoring values on the original MoCA differ from each other significantly in their difficulty level and can be summed to yield a reliable estimate of cognitive ability across a wide range. In a previous study we presented the ranking of the original MoCA items by their difficulty level using the Rasch methodological approach. The reliability of these two alternate MoCA versions has not yet been demonstrated although German-language translations of the original version and two alternate versions were shown to yield similar total scores and to effectively discriminate MCI patients from healthy controls. ( 4) Recently, two alternate English versions of the MoCA (i.e., Alternate Version 2 and Alternate Version 3), in which items from the original MoCA were replaced by alternate items with similar content, were developed with the goal of avoiding practice effects when the test is administered repeatedly within a short period of time ( ). However, it is increasingly used in settings and with populations far different from those for which it was developed, including younger populations who may be more likely to show practice effects with repeated administration. ( 1, 2) Practice effects in mixed groups of older persons with Alzheimer’s dementia, mild cognitive impairment, or no cognitive impairment appear to be minimal, with estimates of around 1 point increase over a 1 month interval, ( 2, 3) suggesting that the MoCA could be used to monitor cognitive status over time. The MoCA test was developed to detect mild cognitive impairment (MCI) in older populations with suspected cognitive decline. Key words: cognition, geriatrics, MoCA, cognitive impairment, alternate forms INTRODUCTION The results suggest that better match of the items from different MoCA forms by their difficulty would result in higher sensitivity to changes in cognitive function over time. This study demonstrates the potential benefits of a Rasch analysis-based approach for selecting items during the process of development of parallel forms. None of the five items from the alternate versions matched the difficulty level of their corresponding original items. ![]() Rasch analysis was used to estimate the difficulty level of the items. Methodsįive selected items from alternate versions of the MoCA were included with items from the original MoCA administered adaptively to geriatric outpatients (N = 78). ![]() The objective of this study was to compare the difficulty of the alternate MoCA items to the original ones. We hypothesized that measurement error when using the new alternate MoCA versions to monitor change over time could be related to the use of items that are not of comparable difficulty to their corresponding originals of similar content. ![]() The Montreal Cognitive Assessment (MoCA) is a screening tool for mild cognitive impairment (MCI) in elderly individuals. Comparison of Alternate and Original Items on the Montreal Cognitive Assessment Comparison of Alternate and Original Items on the Montreal Cognitive AssessmentĮlena Lebedeva, PhD 1, Mei Huang, BSc 1, Lisa Koski, PhD 1, 2ġThe Research Institute of the McGill University Health Centre, Montreal, QC ĢDepartment of Neurology & Neurosurgery, McGill University Health Centre, Montreal, QC
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