Some medical procedures have been characterized as "halfway technologies", while at least some are close to being completely effective. what accounts for the difference? what "halfway technologies" of the past have become much more effective today? why has this advance occurred?

In the health care world, there are three levels of health care and one of them is known as "halfway technologies". Halfway technology is a term which Lewis Thomas used to  describe an obviously unsatisfactory situation that is still  the best available choice. These technologies include methods or therapies which do not get rid of diseases but at least postpone their effects. For example, the iron lung was a a typical halfway technology. It was definitely an improvement for those suffereing from lung diseases but it wasn't even close to offer a serious solution.  

Nowadays, just like in most fields, technology has gained a key role in the health of most human beings. Organ transplantation is a great example of how a "halfway technology" from the past took a step forward saving thousands of lives all throughout the world.  The explanation of why this advance has occured could be justified with the technical change in medicine and the advances in the biological sciences.

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