Cannabis: a Trojan horse for nicotine?

The paper by Smith et al., 'Birthweights and growth of infants in five Aboriginal communities', examines the effect of an intervention on two important characteristics -birthweight and child growth. 1 Various aspects of this paper are worth commenting on.Although there is much discussion of the differences in growth between term and preterm children, the authors could rarely determine the actual basis of the gestational age estimate. 1In the pre-intervention phase, the mean birthweight of term non-low birthweight girls was 30 g higher than boys, which is unusual.There were also twice as many preterm girls as boys when there should be no association between sex and preterm delivery. 2These observations suggest misclassification of small babies as preterm.However, the debates surrounding the determination of gestational age in Aboriginal infants in rural and remote locations cannot be resolved using routinely collected data, such as the Perinatal Collection, with estimates made by many different individuals using unstated methods.The presentation of the growth data and the various comparisons discussed by the authors are difficult to follow owing to the multiplicity of tables and small graphs.Because weight is used, separate charts and tables are needed for boys and girls.