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The information requested is not available centrally. However, a project undertaken by the Dyslexia Institute in Yorkshire and Humberside looked at the incidence of dyslexia and related learning disabilities among the prison population. The findings suggested that 20 per cent. of the prison population have some form of unseen (hidden) disability which will affect and undermine their performance in both education and work settings. A further 32 per cent. of the sample who were given an in-depth assessment had literacy difficulties but did not show positive evidence of the characteristics of dyslexia, dyspraxia or other unseen disabilities.