Handedness and allergic disorders in a New Zealand cohort.

Studies of the proposed association between handedness and allergic disorders have shown results which appear contradictory. In view of differences in the procedures of these studies, further tests of the strength of this association are warranted. Results from this study of a large birth cohort of children showed no support for an association between handedness measured at age 7 years and reports of eczema, urticaria, rhinitis, or asthma in late childhood or early adolescence. There was no significant association found between handedness and reported frequency and duration of symptoms of wheezing, or parental help-seeking for these symptoms. Apparent differences in the results of these studies could possibly be reconciled by the view that preference for use of the left hand may be associated with increased help-seeking behaviour in later life for a range of problems or difficulties. Further tests of the association between handedness and disorder in clinical samples require more rigorous control procedures.