Fig. 6From: Handedness in twins: meta-analysesa Moderating effect of publication year on twin-to-singleton ORs for left-handedness. The twin-to-singleton OR for left-handedness decreases as the publication year of the individual study increases. This effect could be due to a decrease in left-handedness prevalence in twins, an increase in left-handedness prevalence in singletons, or both. b Association between publication year and left-handedness prevalence in twins. c Association between publication year and left-handedness prevalence in singletonsBack to article page