I’m going to use my survey results, research and practical experience of D&D to creative a list of skills that I think that I have developed from playing D&D. Then I will make a second list of skills that are specific to DMing, since although both sets of skills overlap, there are additional skills that being a DM both requires and develops, for example, organisational skills of keeping track of the whole world that you develop and run. You can use pre-existing worlds and campaigns from D&D books when you start, indeed I did, but most DMs end up wanting to create their own worlds. And even if you use a pre-created world, you still have to keep track to ensure consistency and continuity throughout the game.
I must remember to keep referring specifically to being a DM, rather than just general playing D&D. However, it is helpful to consider both aspects for my research.