I wanted to do a little background prior to signing out this posting. The best link for an actual study that I have found is an actual research study. I can completely understand your frustration and I doubt there's an abundance of standardized measurement tools out there that you can readily use for your paper.
That said, the fact that it was published in a scholarly research publication indicates that has valid implications and may offer you a tool that could be replicated in your own research.
Here's the link I ...
This posting brainstorms instruments to measure teachers' attitudes toward autistic students.