People decide to do research for various reasons. In order to do good research you have to have decent questions to ask. Having decent questions requires knowledge of your subject. It’s a kind of classic catch 22, you have to know what you don’t know in order to find out about what you don’t know when you try to look into it.
I have seen a few doctoral and master’s dissertations in my travels. Some of them have been really excellent but others have been so poor as to be scary. I have to wonder, how is this document worthy of a doctorate????? Who is confirming on this individual that they are so expert when this is written so badly?
Research carried out in a vacuum is hard to understand. It doesn’t apply to real life situations and it isn’t helpful to non-scientists. That doesn’t mean it has no purpose. Science for science’s sake has to exist. We need to prove that water is wet and rocks are hard in order to know that the “real world” is real. But research on voice is done largely in the medical community on throat cancer and vocal fold injury or related topics, not on high level singers who are quite well. There is no financial motive for drug companies to develop drugs that will make lots of money in looking at singing. There may be some motivation for makers of life saving devices that help people survive (remember, the vocal folds have to open and close in order for you to breathe properly and stay alive) while looking at vocal fold function. There is little motivation for finding out how high belters maintain long careers or how sopranos spin out soft stratospheric notes. There may be motivation for doctors to develop new and different techniques in surgery, thereby boosting the success rate of recovery in singers and, thereby boosting the reputation of the hospital, attracting more patients. And, through this heightened reputation, charge more for medical services and make more money for investors.
Research done by singing teachers, typically found in music programs, may be done on students or faculty by students or faculty. This, too, is probably necessary, but it isn’t  always helpful since it hardly reflects real world conditions that singers face in their careers.
It is very difficult to understand the relevance of research without the proper context. At a recent  medical conference there was a paper comparing the vibrato rates of jazz singers to those of  classical singers. This research was full of measurements and statistics. The conclusion was that classical singers use vibrato more consistently and that the vibrato rate was slower and the extent wider than the jazz singers.  OK. We needed a study to tell us this? This is helpful to whom? So much time and energy was put into this study and its presentation by its author (a doctor from Europe). Should we conclude that listening to the two styles extensively would not have been enough to draw this conclusion without any formal research?
When reading voice research, think about its relevance. If you are doing voice research, think about its relevance. If you don’t know that you don’t know, you can at least try to find someone who does know who could give you some guidance. Please don’t tell us things we can conclude on our own if we use our eyes, ears and common sense.