When can I take an online survey?

You can take an online survey at any time before the deadline shown in the invitation. However, we recommend completing it as soon as possible, as studies may close once enough participants have responded.

If the study is already full or no longer available, you will see a message when you try to access it.

We also recommend completing the survey in one sitting. As many people may be responding at the same time, we cannot guarantee that a place will still be available if you leave and return later.