Wehby George L
University of Iowa, Departments of Health Management and Policy and Economics, 105 River St, CPHB, N248, Iowa City, IA, United States; National Bureau of Economic Research, United States.
Econ Hum Biol. 2014 Dec;15:13-22. doi: 10.1016/j.ehb.2014.05.004. Epub 2014 May 28.
Little is known about whether breastfeeding may prevent disabilities throughout childhood. We evaluate the effects of breastfeeding on child disability using data from the National Survey of Family Growth merged to the National Health Interview Survey for a large nationally representative sample of children aged 1-18 years from the U.S. including over 3000 siblings who are discordant on breastfeeding status/duration. We focus on a mother fixed effect model that compares siblings in order to account for family-level unobservable confounders and employ multiple specifications including a dynamic model that accounts for disability status of the prior child. Breastfeeding the child for a longer duration is associated with a lower risk of child disability, by about 0.2 percentage-points per month of breastfeeding. This effect is only observed on the intensive margin among breastfed children, as any breastfeeding has no effect on the extensive margin. We conclude that very short breastfeeding durations are unlikely to have an effect on reducing disability risk.
关于母乳喂养是否能预防儿童期的残疾，人们所知甚少。我们利用《全国家庭成长调查》与《国家健康访谈调查》合并后的数据，对美国1至18岁具有全国代表性的大量儿童样本进行研究，以评估母乳喂养对儿童残疾的影响，其中包括3000多名在母乳喂养状况/时长方面存在差异的兄弟姐妹。我们重点关注一种母亲固定效应模型，该模型通过比较兄弟姐妹来考虑家庭层面不可观察的混杂因素，并采用多种设定，包括一个考虑前一个孩子残疾状况的动态模型。母乳喂养孩子的时间越长，儿童残疾风险越低，每母乳喂养一个月，风险降低约0.2个百分点。这种效应仅在母乳喂养儿童的强度边际上观察到，因为任何母乳喂养对广度边际都没有影响。我们得出结论，极短的母乳喂养时间不太可能对降低残疾风险产生影响。
