I want to ask for advise on how to improve the response rate of a running study.
I am currently running a study for German prolific users. Prolific estimates are that ~1300 users are eligible for the study and were recently active on the platform. I need about 1000 participants. However, the study is active for 14 days and I have yet received only little more than 500 responses. I am paying £2.2 for a 14 minutes survey, i.e. an hourly rate of £9.42. As of now the 500 users that participated received an average reward per hour of £14.
Is there any way to increase the scope of the study and the number of eligible participants?
When I pause the study, can I remove pre-screening factors?
Does it make sense to stop the study and run a new one to get the last 500 participants?
Thanks for your help.