In my experience in the UK we do not pass over testimonials, work samples, exam certificates at an interview.
In my experience in the US some of this is appropriate to have
available at an interview but not necessarily to hand out immediately upon entering the room. It's always helpful to have a few copies of your resume/CV with you, especially if you're at a panel interview. Often it's just the head of the interviewing committee who will have a copy so if you want to reference something (i.e. "as you can see by my resume...") it's helpful to make sure everyone has a copy to look at. However, things like certifications, letters of reference, exam results are usually given to the HR department once a job offer has been made.