1 Department of Pediatrics, Division of Allergy and Clinical Immunology, National Jewish Health, Denver, Colo.
2 Division of Biostatistics and Bioinformatics and Department of Immunology and Genomic Medicine, National Jewish Health, Denver, Colo; Department of Epidemiology, Colorado School of Public Health, Aurora, Colo.
3 Department of Pediatrics, Division of Allergy and Clinical Immunology, National Jewish Health, Denver, Colo. Electronic address: leungd@njhealth.org.