In a medical malpractice case, can an expert's professional judgment be based solely on third-hand information?

In Regina v. Lavallee, [1990] S.C.J. No. 3666 at para. 83 Sopinka J. stated: …an expert arrives at an opinion on the basis of forms of inquiry and practice that are accepted means of decision within that expertise. A physician, for example, daily determines questions of immense importance on the basis of observations of colleagues, often in the form of second or third hand hearsay. For a court to accord no weight to, or to exclude, this sort of professional judgment, arrived at in accordance with sound medical practices, would be to ignore the strong circumstantial guarantees of trustworthiness that surround it. And would be, in my view, contrary to the approach of this court taken to the analysis of hearsay evidence in general…