“The main focus of our analysis is assessing access to primary-care physicians under the health-care law. The reason for this focus is twofold: first, we already know that we will be facing a primary-care shortage in the coming years, so understanding the role that Obamacare plays in affecting the shortage is important; second, much of the law was motivated by the argument that expanding access to inexpensive (or free) preventive care and primary care physicians would ultimately bend the curve of health-care spending.”