Just a small comment from my own experience devising surveys. Don't ask
for the age of people. If you really need that information, ask for
birth YEAR. People will fill that in more readily than fill in age. (This
is true, I don't know why.)
And if you can (although I know it's a misery for coding), leave as many
questions as you can open-ended--e.g., ask for ethnic background, and
suggest that it can be mixed, or diverse or simply whatever the participant
wants to say. (Some will say "Human Race" and that's fine, too.) But don't
make an "identity question" one that's precoded. People hate being slotted
into categories.
Best wishes,
Maureen Korp, Ph.D.
University of Ottawa