ed. There were also tremendous local differences in the amount and type of training required, and how it would be provided. This ranged from in service training in local systems, through community colleges, and ultimately even to universities. In the U.S. the community college training model remains the most common, although university-based paramedic education models continue to evolve. These variations in both educational approaches and standards led to tremendous differences from one location to another, and at its worst, created a situation in which a group of people with 120 hours of training, and another group (in another jurisdiction) with university degrees, were both calling themselves 'paramedics'. There were some efforts made to resolve these discrepancies. The National Association of Emergency Medical Technicians (NAEMT) along with National Registry of Emergency Medical Technicians ((NREMT) attempted to create a national standard by means of a common licensing examination, but to this day, this has never been universally accepted by U.S. States, and issues of licensing reciprocity for paramedics continue, although if a EMT obtains certification through NREMT (NREMT-P, NREMT-I, NREMT-B), this is accepted by 40 of the 50 states in the United States. This confusion was further complicated by the introduction of complex systems of gradation of certification, reflecting levels of training and skill, but these too were, for the most part, purely local. The only truly common trend that would evolve was the relatively universal acceptance of the term 'Emergency Medical Technician' being used to denote a lower lever of training and skill than a 'Paramedic'.
During the evolution of paramedicine, a great deal of both curriculum and skill set was in a state of constant flux. Permissible skills evolved in many cases at the local level, and were based upon the preferences of physician advisers and medical directors. Treatments would go in and out of fashion, and sometimes, back in again. The use of certain drugs, Bretylium for example, illustrate this. In some respects, the development seemed almost faddish. Technologies also evolved and changed, and as medical equipment manufacturers quickly learned, the pre-hospital environment was not the same as the hospital environment; equipment standards which worked fine in hospitals could not cope well with the less controlled pre-hospital environment. Physicians began to take more interest in Paramedics from a research perspective as well. By about 1990, most of the 'trendiness' in pre-hospital emergency care had begun to disappear, and was replaced by outcome-based research; the gold standard for the rest of medicine. This research began to drive the evolution of the practice of both paramedics and the emergency physicians who oversaw their work; changes to procedures and protocols began to occur only after significant outcome-based research demonstrated their need. Such changes affected everything from simple procedures, such as CPR, to changes in drug protocols. As the profession of paramedic grew, some of its members actually went on to become not just research participants, but researchers in their own right, with their own projects and journal publications.
Changes in procedures also included the manner in which the work of paramedics was overseen and managed. In the earliest days of the field, medical control and oversight was direct and immediate, with paramedics calling into a local hospital and receiving orders for every individual procedure or drug. This still occurs in some jurisdictions, but is becoming very rare. As physicians began to build a bond of trust with paramedics, and experience in working with them, their confidence levels also rose. Increasingly, in many jurisdictions day to day operations moved from direct and immediate medical control to pre-written protocols or 'standing orders', with the paramedic typically only calling in for direction after the options in the standing orders had been exhausted. Medical oversight became driven more by chart review o