You’re going to analyse each paper against the same themes. It’s up to you to come up with those themes, based on what you already know of your subject. You can have as many themes as you want, but don’t over do it. You don’t want to end up with a theme that is only used for one of the ten papers you’re comparing.
The trick is, you might not know, when you begin, exactly what your themes are going to end up being. So you need to be flexible. If you see a new theme emerging, add it to your table, and go back to the previous papers you’ve read to check if you can add any interesting information about it in the new cell.
And if you end up not having that much information about one of the themes you had previously written down, do not hesitate to delete it. Or ask yourself how come there is no info on this… Maybe you should search for other papers on this topic?
You’re also allowed to leave cells blank. It happens. Not every papers talks about everything.
The note taking matrix – How To Do A Literature Review