The rate of handedness conversion and related factors in left-handed children

Abstract

The rate of handedness conversion was 2.7% to 11.8% in prior studies based on the total population including innately right-handed people. However, the conversion rate of innately left-handed people has not been reported. The purpose of this study was to investigate the percentage of handedness conversion in children who are innately left-handed. The data in the present study showed that 59.3% (121/211) of left-handed children had been forced to convert to right-handedness. Current handedness was also reported by 114 of the 121 informants, and the rates of right-, left-, and mixed-handedness were 56.1% (64/114), 26.3% (30/114), and 17.5% (20/114) respectively. More than half had successfully changed from left to right. Some variables, especially the educational level of the parents and the child's grade level, were related to this conversion intention. The children whose parents had less education were more likely to be forced to change handedness. Additionally, the rate of handedness conversion in younger children was lower than in older children. However, even for the children whose parents had higher education, or for the children who were younger, there was a high percentage (45.7% and 41.8% respectively) who had changed their handedness. Therefore, preventing the possible side effects for children who have undergone hand conversion should be emphasised in the future.

Acknowledgments

The author thanks the caregivers and teachers who responded to the questionnaire. The author would also like to thank the teachers and children of Shyr-Jiann elementary school, Muzha kindergarten, and Jingmei kindergarten included in this study for their help in questionnaire collection. This research was supported in part by two grants from the National Science Council (NSC 94-2413-H-182-003) and the Chang Gung Memorial Hospital (BMRP 424) in Taiwan.