Proof-reader checks, edit and reviews a document, article or a dissertation before it is published. Generally, the duty of a proof-reader is to check if the document stands upon the requirement of publication or not. However, he/she might also suggest some changed before the final publication of the paper. On the other hand, we have UK top proof-readers by our end who are proficient in proofreading dissertations under very short deadlines.
It highly depends on the person editing the dissertation. Generally, 15000 words of a dissertation take about 2 to 4 weeks to be written and approx. a week to be edited (if it’s being edited by a professional). However, if an amateur or a student is editing 15000 words of a dissertation it might take more than a week.