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Statistical moderation of school-based assessment in GCSEs

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Williamson, Joanna 


Moderation of school-based assessment (SBA), such as coursework, is required in order to ensure the comparability of marks across different centres. Under current procedures for GCSEs, moderators re-mark a sample of SBA from each centre in order to check whether any adjustment should be made to that centre's marks. This article explores statistical moderation, an alternative form of moderation that calibrates SBA marks on the basis of a statistical relationship with another assessment, such as an exam component. The article outlines methods of statistical moderation that are used in jurisdictions around the world, and explores the effect of applying these methods to results data from three GCSEs. The analysis focuses on comparing the statistically moderated results to operational results (moderated under existing, non-statistical procedures) in terms of marks, grades, and the rank-order of candidates and centres.



Examination statistics, Marking, GCSE/IGCSE

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Research Matters

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Research Division, Cambridge University Press & Assessment

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