Transient environmental effects detected in sibling correlations.
Detection of environmental effects in sibling correlation is difficult. Mueller (1978) has proposed that transient environmental effects should be associated with a decrease in the sibling correlation with increasing age difference between members of a pair of adult sibs. The present report suggests that an environmental effect can also be detected by partialing out environmental indicators from correlations between sibs measured at the same chronological age. Correlations for 12 variables were computed between 208 pairs of 10-year-old French-Canadian sibs from Montreal. Partialing out seven socio-economic indicators from these correlations resulted in significant changes for three skeletal measurements as well as for body weight and triceps skinfold. These results differ from those reported earlier. The proposed method may be sufficiently sensitive to detect environmental effects, provided simple assumptions are met.
D000886:Anthropometry; D002648:Child; D002657:Child Development; D005190:Family; D006801:Humans; D012959:Socioeconomic Factors