There are several stages which are detailed on the GSK website; application form, online assessment, motivational questions, video interview and then AC. Online assessment has both a SJT and numerical mixed in, motivational questions for me was just two questions about why GSK and my chosen programme. Video interview (which is the stage I am at, haven't heard back) was the most difficult of all. Most questions are competency based but if you are doing something science-y or technology related you will also have technical questions.