Hi,
That's no problem at all. A lot of people start their initial work in a solo review (especially as they can do this at no charge i.e. can have any number of solo reviews as they wish), and then - once they have set up their initial code sets / gathered their initial references - share it with co-screeners, other participants, etc.
All information is retained, as are codesets, any existing coding / screening information, etc. (Basically it is the same review, but now set so others can have access to it as well.)
The sharing can be done at various levels - you can allow others just to code existing references, have general access (import references, screen, code, etc.), or full administratrive access (whereby you can grant or rescind access for others.).
To change an existing solo review to a shared review,
You can do this at the Account Manager, at https://eppi.ioe.ac.uk/cms/Default.aspx?tabid=2935
Log in (and confirm your address, if you haven't done so), then click the Purchase tab. You can then share your review for the number of months you wish. (Select the number of months in the drop down box next to the review.)
There are videos detailing how to invite other users into your shared review online, available via https://eppi.ioe.ac.uk/cms/Default.aspx?tabid=2933
Do let us know if you require any further information or assistance. Our support email address is EPPISupport@ucl.ac.uk
Kind regarards,
Zak