Once again, an Illinois appellate court has ruled that there is nothing magic about the phrase "based upon a reasonable degree of medical certainty," which lawyers often use to preface their questions to experts about their opinions. In Hahn v. Union Pacific, No. 5-03-0466 (5th Dist. 2004), the court stated as follows--
There is no magic to the phrase itself. The phrase provides legal perspective to medical testimony and signals to the jury that a medical opinion is not based on mere guess or speculation. It is of no consequence that a medical expert witness fails to use this phrase if the expert's testimony reveals that his opinions are based upon specialized knowledge and experience and recognized medical thought.
Id. (citations omitted). This comment was made in the context of a decision reversing the trial court's grant of summary judgment for the defendant in an FELA case. The case also contains an analysis of the "might or could" standard for proving causation.