It is possible to run diary studies on Prolific. These can be complex to set up, so below we have outlined possible options for how these studies can be run on Prolific.
It's important that you make the requirements of your study as clear as possible in your study description so that participants can make an informed decision as to whether they wish to commit to the study. You should also ensure that you obtain full informed consent from participants before they complete the first diary session.
We recommend following a similar two-step approach as used when recruiting a custom sample.
This study would be used to describe the full procedure, obtain full informed consent from participants, and allow them to answer any screening questions to determine their eligibility for the diary study.
The reward for this study can be small if the study is short, and you should ensure that you collect participant IDs so that you can invite eligible participants back to your main diary study.
You'll need to approve all submissions to this initial study, even if they indicate that they don't wish to take part in the main diary study.
Main diary study set up
You can invite eligible participants back to your main diary study by using a custom allowlist.
You should ideally run one study on Prolific per timepoint in the study. If the diary study requires participation at multiple times throughout the day, you may set up one study on Prolific per day, rather than per time point. You can then manage the completion of multiple sessions on each day within your external study software or using our messaging system.
For example, when you launch your study at the beginning of the day on Prolific this would direct participants to the study URL for the first session. You would then send the URLs for the subsequent sessions that day to the participants in a bulk message using our messaging system.
You have two options for paying participants for the main diary study:
Set the reward for each diary study on Prolific to reflect the payment for session one only. Once participants complete further studies throughout the day (using the links provided via the messaging system), you can then award bonus payments to cover the payments for these submissions.
An advantage of this approach is that you can approve the submission after completion of session one, but a disadvantage is that you would need to calculate the bonus payments to ensure that they pay at least our minimum reward rate of £5 / $6.50 for the time participants spent on further submissions
Set the reward for each diary study on Prolific to reflect payment for all sessions that day. This way, you would wait until all sessions had been completed that day and then approve the participants' submissions on Prolific.
An advantage of this approach is that you would need to make fewer bonus payments, assuming that most participants complete all sessions on that day. A disadvantage is that you may need to award partial payments to those participants who partially complete the day's sessions. Furthermore, these partially completed submissions will need to be returned, rather than approved or rejected. This can only be done by the participant or by the Prolific Support Team.
Pilot your study
We strongly recommend that you run a pilot study. This will give you an opportunity to check that everything is working as expected, and that participants understand what they need to do.