In Marso v. Novak (42 AD3d 377, 840 NYS2d 53 [1st Dept 2007]) the court refined its earlier pronouncement in Nonnon. In Marso, the plaintiff suffered a stroke and sued his doctor claiming the stroke was caused by a slow heart rate (bradycardia) which his doctor failed to address. Indeed, the plaintiff sought to introduce expert testimony that the stroke was caused by bradycardia, although the expert conceded that there was no acceptance within the scientific community that a stroke is a risk factor of bradycardia. The conclusion reached by the expert was therefore based upon a differential diagnosis, a process of elimination which excludes all other causes. The court rejected the reading of Nonnon v. City of New York as permitting the introduction of any expert evidence provided the methodology is acceptable. The court stated that the "plaintiff interprets Nonnon to mean that generally accepted methodology such as differential diagnosis when properly performed leads to admissible expert conclusions. This case prompts us to add \`but not when there is a generally or widely held view in the scientific community rejecting such conclusions outright.' In this case, plaintiff's expert's own unambiguous answer at trial was that the result generated, which purportedly confirmed the expert's initial theory, was not accepted in the medical community." (Id. at 378, 840 NYS2d 53.)