1. Center for Observational and Real-World Evidence, Merck & Co. Inc., 351 North Sumneytown Pike, North Wales, PA 19454, USA
2. Center for Observational and Real-World Evidence, Merck & Co. Inc., Rahway, NJ, USA
3. Center for Cough, Largo, FL, USA
4. Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
5. RTI Health Solutions, Research Triangle Park, NC, USA