If the average reward per hour for your study falls below the minimum rate required (£6 / $8 per hour), you will need to adjust the participant payments to bring this up to at least the minimum rate:
If the average reward per hour drops below your estimated rate but is still above the minimum, we recommend adjusting the payment to be in line with the estimate, however this is not required.
Prolific uses the median completion time to work out your study's average reward per hour so that extreme completion times do not skew the data. In order to help avoid your studies being underpaying we recommend running a pilot study with a small number of participants.
What happens if my study falls below the minimum payment rate?
If your study is still active:
- We’ll pause it, and contact you.
- We’ll ask you to pay the appropriate adjustment payment amount to participants who have completed your study.
If your study is complete:
- We’ll contact you, and ask you to pay the adjustment payment amount to participants who have completed your study.
- If you need more participants for your study, mark the initial study as “complete”.
- Then duplicate the initial study and increase the estimated completion time and reward.
- You'll need to add the ‘exclude participants from previous studies’ prescreener to your study to avoid participants taking both versions of the study
If there is no response to the message we send you within a reasonable amount of time:
- Your account might be temporarily frozen.
- If we receive a response indicating that appropriate steps have been taken to resolve the issue, we will reinstate the account.
How to resolve an underpaying study with adjustment payments
If one of your studies is paying below the prolific minimum, you will see an alert on the study submissions page and also receive an email from Prolific:
If a study is paying below your original estimated reward rate, you will also see an alert on the submission page, but will not receive an email:
The option to pay adjustment payments will only appear once at least one submission has been approved, or at least 50% of the study places have been filled.
In order to address this, you can adjust the reward per hour to either the minimum reward per hour (if applicable), or your original estimate, which is the price you initially selected when publishing the study. Simply click the 'Adjust reward per hour' link and you will see the following screen where you can choose between these two options:
Please note that you may need to top up your account to make these adjustment payments as they will not have been factored into your original study cost calculation.
If you increase the reward rate before approving submissions, no money will be immediately paid. Instead, money will be reserved from your total Prolific balance for payments you'll make to participants after approving submissions, or automatically 21 days after submissions are received.
If you’ve already approved submissions, these participants will be awarded an additional payment to bring their reward in line with the new rate you have selected. If some of your submissions are unapproved, money will be reserved from your total Prolific balance for these payments. These participants will receive one payment of the new total reward value.
Below is what a participant will see if their submission was approved before the adjustment:
When you adjust your reward per hour, you might find that you need to top up your balance. You'll see a notification at the top of the adjustment screen where you can top up with the indicated amount. You will need to have enough money in your account in order to adjust your reward per hour.