Department of Biostatistics, University of Pittsburgh Graduate School of Public Health, Pittsburgh, PA, USA.|Division of Pulmonary Medicine, Allergy and Immunology and Department of Pediatrics, Childrens Hospital of Pittsburgh of UPMC, University of Pittsburgh, Pittsburgh, PA, USA.|Center for Statistical Science, Tsinghua University, Beijing, China.|Department of Quantitative Health Sciences, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, OH, USA.|Division of Rheumatology and Clinical Immunology, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.|Department of Biostatistics, University of Pittsburgh Graduate School of Public Health, Pittsburgh, PA, USA.|Department of Quantitative Health Sciences, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, OH, USA.|Department of Biostatistics, University of Pittsburgh Graduate School of Public Health, Pittsburgh, PA, USA.