I presume you are wanting to investigate performance based on different shoeing techniques.
I cannot see how this survey will help in any way shape or form. All the end questions completely eliminate horses that are shod regular, sound and owners have never felt the need to change shoeing. They are all eliminated from your survey as they cannot answer the last questions, and cannot be used to compare before and afters.
There will be a small number of people who can answer your survey based on changing shoeing techniques but without the complicated factor of physical issues with the horse.
What you need to consider is that the majority of people changing shoeing will have done so for a specific reason, now is the change in performance related directly to the shoeing or is it possibly that it could be partly due any concurrent changes to horse management/feeding/drugs etc.
For that reason I fear you may be completely wasting your time with this survey and it is really worrying that this is part of a degree