Hans Christian Andersen's spelling and syntax: allegations of specific dyslexia are unfounded

Sources contemporary with Danish author Hans Christian Andersen claimed that he did not master the Danish language, which modern studies interpret as specific dyslexia. A systematic study of his diaries from age 20 to age 70 found a mean spelling error percentage of approximately 1.7 (SD = 1%, range = 0%-4%). A methodologically independent reliability study confirmed these figures. Andersen's error percentages in poems and letters from ages 11 to 19 show a typical initial part of a learning curve that, together with the results from the diaries, gives a life span curve of his spelling development. The diaries, letters, and poems contain only insignificant syntactic errors. Andersen's spelling in the above studies is compared with that of his contemporaries and with data from modern studies. His mean error percentages at different ages are equal to the figures from nondisabled participants, but between 2 and 15 times lower than the mean percentages in studies of individuals with dyslexia. A structural analysis of Andersen's spelling errors shows that they are mainly phonologically plausible from ages 11 to 70, and that the proportions of plausible/implausible errors match those of normal achievers, but not those of individuals with dyslexia.