Department of Biostatistics and Informatics, University of Colorado Anschutz Medical Campus, 13001 E. 17th Place, B119 Bldg. 500 W3128, Aurora, CO, 80045, USA. sharon.lutz@ucdenver.edu.|Department of Biostatistics and Informatics, University of Colorado Anschutz Medical Campus, 13001 E. 17th Place, B119 Bldg. 500 W3128, Aurora, CO, 80045, USA.|Department of Biostatistics and Informatics, University of Colorado Anschutz Medical Campus, 13001 E. 17th Place, B119 Bldg. 500 W3128, Aurora, CO, 80045, USA.|Department of Biostatistics and Informatics, University of Colorado Anschutz Medical Campus, 13001 E. 17th Place, B119 Bldg. 500 W3128, Aurora, CO, 80045, USA.|Department of Pediatrics and Pulmonary Medicine, Childrens Hospital Colorado, Aurora, CO, USA.|Department of Epidemiology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA.|Department of Epidemiology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA.|Department of Biostatistics and Informatics, University of Colorado Anschutz Medical Campus, 13001 E. 17th Place, B119 Bldg. 500 W3128, Aurora, CO, 80045, USA.