Is an ACCME-accredited provider required to use a sign-in sheet at CME activities?

No!  Any method can be used, as long as some record of learner participation can be verified for at least 6 years, per the ACCME’s policies on Attendance Record Retention.   Another example of tracking physician attendance would be to include learners seeking credit to submit an application for credit including an attestation to the time the learner attended the activity.