Thanks, but if the the information of "participation" is important to disclose, isn't it better to use "participation". In some part of the world I think there is a wrong practice, such as: "Confirm your appearance in exam."
That's fine in BrE - you can take or, more formally sit an exam(ination). After the results come out, you know whether you have passed or failed it. What L7 may be needing is some form of official 'confirmation of attendance'. The candidate could then show this certificate to, for example an employer who had granted leave for the examination, confirming that s/he had indeed attended/sat/taken the examination.