If you have concerns about academic integrity, you may wish to add an academic integrity statement to your exam. An academic integrity statement could be a request for the student to acknowledge that they are completing the exam without any help from a third party and/or without consulting their notes, the textbook or other sources (unless, of course, it is an open book exam).
To see an example of how an academic integrity statement can be set up in Moodle consult the following document.