The experimental protocols were approved by Institutional Review Board (IRB) of each participating centers of COGA: University of Connecticut; Indiana University; University of Iowa; SUNY Downstate; Washington University in St. Louis; University of California at San Diego; Rutgers University; University of Texas Health Science Center at San Antonio, Virginia Commonwealth University, Icahn School of Medicine at Mount Sinai, and Howard University. Data were collected from the first six of these eleven centers. All participants signed an IRB approved written consent form. Parents or legal guardians signed for their minor children. Consent was obtained by research personnel who had adequate training and competency in ethical guidelines and consent process. Study procedure, risks and benefits were explained to each participant and/or the parent/guardian before collecting data. It was also ascertained that participants were not disadvantaged in any way by not participating in the study.
