Initial HR phone screening interview with standard experience questions: you'll go through your resume and ensure you meet the minimum qualifications per the job description. If you do not fit the job description to a tee, you will not pass this step--i.e. if it requires a PhD and you have a MS + 20 years of research experience you still will not pass.
Interview day: depending on your anticipated role, you may or may not be asked to give a research talk (45 min. presentation, 15 min Q&A). You will be notified of this well in advance.
You will meet with 4-5 individual interviewers during the day. No group interviews will be held (from what I know). The panel selected will certainly include your direct supervisor, most likely his/her superior, and one or two members of varying rank in the research group. Everyone will ask questions about your research experience. Some may be more technical than others. Some will stick mostly to culture questions/ask you things to get a better feel for your personality. Just be yourself! The interviews were very relaxed and the people here are extremely friendly. Everyone seems to want to know you as a person first--your skills and experience they can tell more readily through your education, work experience and job references, and seem to be less of a concern on interview day.
Good luck! Abbott is a great company!!