noun
cooperation fee; compensation; reimbursement
A payment made to someone for their participation or cooperation, such as in a clinical trial, survey, or study. Often used in formal or institutional contexts.
治験に参加すると、協力費として謝礼が支払われます。
If you participate in a clinical trial, a gratuity will be paid as a cooperation fee.
アンケートに回答した方には、協力費として図書カードを進呈します。
Those who complete the survey will receive a book card as compensation for their cooperation.
報酬 is a broader term for remuneration or compensation for work or services, whereas 協力費 is narrower, often used for participation incentives.
Compound of 協力 (cooperation) and 費 (expense, cost). The term is a modern coinage used in administrative and research contexts.