EB1B Job change

If I really need to change employer, do I only need to make sure the job code on Supplement J provided by the new company is identical to my current company? Do I have to obtain a research position? And would USCIS ask for other documents apart from the Supplement J form?
I just really hate my current job so much and can't wait to leave my current employer.

It would be the best if you secure a researcher/scientist position. But I don't think it is necessary.