JAMA September 6, 2016 2016 Powers BW, Rinefort S, Jain SH http://www-ncbi-nlm-nih-gov.ezp-prod1.hul.harvard.edu/pubmed/?term=Nonemergency%20Medical%20Transportation%3A%20Delivering%20Care%20in%20the%20Era%20of%20Lyft%20and%20Uber