Handedness and dyslexia: a meta-analysis.

The question whether there is an association between handedness and dyslexia has been investigated in many studies spanning more than 50 years. In 1990, Bishop reviewed studies which met stringent methodological criteria and concluded that there was little support for an association. A reanalysis of the same studies using newer procedures of meta-analysis shows that there is a small but reliable increase in the proportion of nonright-handers among dyslexics as expected by the right-shift theory of handedness of Annett.