many years ago now a cohort of our nursing auxiliaries (that is what they were called then) took the training and switched to being phlebotomists. I used to need regular blood tests and would always choose to go to one of them because they were so good at it. It was their only paramedical job, not an add on to other things, they all trained to do it because they wanted to do it and it mattered that they should do it well because it was the only thing they did. Not all of them were full time, some did other jobs as varying kinds of medical admin.