For this bit of research, I’m going to be looking at the survey that explains where the 97% value comes from.
I’ve created a video that is basically an easier way to look at this article. The details and links are the same as this written version, but a lot of people find watching easier to understand than the reading.
Also, underneath are the links to the actual article, so that you can read at your leisure etc. They’re in pdf and word (zipped) versions.