English to Spanish Marketing Marketing software/hardware evaluation survey

it's the heading to an email invitation for an online survey; the full title is:

"Invitation to the PAID business research study you agreed to participate in"

I'm just wondering how to translate "paid" in this context, so that it's clear that participants will get paid/compensated for their participation, not that the study itself has been paid for.

Also, "business" refers to the fact that it's a business-to-business study (i.e. the company conducting the study is surveying businesses, NOT the general consumer population).