We conducted this trial between November 2006 and March 2009 at the Children's Hospital of Pittsburgh and Armstrong Pediatrics, an affiliated private practice in Kittanning, Pennsylvania. The study protocol was approved by the institutional review board at the University of Pittsburgh; written informed consent was obtained from a parent of each enrolled child. The protocol, including the statistical analysis plan, is available with the full text of this article at NEJM.org. The authors attest that the study was performed in accordance with the protocol and the statistical analysis plan.
研究実施計画は、ビッツバーグ大学治験審査委員会によって承認されました:書面による同意書は登録するそれぞれの子供の親から得られました。統計上の分析計画を含む実施計画は、MEJM.orgにてのこの記事の全文とともにご覧いただけます。著者は、研究が実施計画と統計上の分析計画に従って実施されたことを証明しています。