Methods
This study is a retrospective review of all pediatric patient (<18 years) electronic medical records who were diagnosed with IH at large, tiertiary medical center in the United States between August 2009 to July 2017. We adhered to the STROBE reporting guideline to insure our study follows the standards for reporting observational studies. Approval was obtained from our institutional review board with a waiver of informed consent due to the retrospective nature of this study. Patient demographics, IH clinical features, and treatment data were extracted from the electronic medical record. Race and ethnicity, self-reported in clinic intake forms, were gathered from the medical record. All electronic medical record data collected during the course of this research was stored within a secure REDCap database, using a unique, encrypted identifier for each patient.
Descriptive statistics, including percents and frequencies for categorical variables, are presented and chi-square test was used for the comparison between groups. Logistic regression was applied to identify risk factors for outcomes of interest with the adjustment of location.