In Daubert: Very Convoluted, Usually Confusing to Many, Nevertheless Elegant, Armand Rossetti writes:
Pretrial Daubert hearings are essentially motions in limine that ultimately decide whether an expert is qualified, and whether that expert: 1) has based an opinion on sufficient facts or data; 2) will be able to testify using “reliable principles and methods,” and; 3) has applied the principles and methods reliable to the particular facts of a given case.
The Daubert factors are based Rule 702 of the Federal Rules of Evidence, which is used to examine an expert’s testimony as a whole. In addition under Rule 703, experts may reasonably rely on documents and information that may be inadmissible during trial. It is also Rule 703 that forms the basis for inquiry, concerning the reliability of any data that supports expert testimony. Furthermore, Rule 703 relaxes the requirement that experts need to acquire personal knowledge about the matter to which they testify. Finally, Rule 703 has little to do with whether an expert’s testimony, as a whole, meets Daubert standards. That determination rests with Rule 702.