What is the best operational definition of shortness of breath?  Is it: shortness of breath is respiratory rate of greater than 25 and a score of greater than three on the "Perceived SOB Scale" or is shortness of breath is a reflection of systemic hypoxia?
Thanks for your question on Chat Doctor. I can understand your concern. Shortness of breath is defined in many ways. There is no particular definition for this. But as doctors, we call it shortness of breath when patient is having rapid breathing, (respiratory rate more than 24 per minute), with use of accessory respiratory muscles with hypoxia (low oxygen saturation). Patient usually describe shortness of breath as breathing difficulty on climbing stairs or fast walking. Some patients describe this as labored breathing. So there is no specific definition for shortness of breath. Hope I have solved your query. I will be happy to help you further. Wish you good health. Thanks.