Rencently I've got the opportunity to observe the following situation that I'd like to share with you:
QA colleagues (one or two people) have been attending the events of several scrum teams. I remark that they attend and not participate, but observe and take notes. The events I've been aware of are mostly daily scrums and sprint reviews, and for the daily scrum they do this 3-4 times randomly throughout a sprint .
They write the gathered data into a document by scoring their observations against some criteria, for example: