What is responsive evidence in a medical malpractice case?

In that decision at para. 51, the court refers to a different form of responsive evidence recognized in Stainer v. Plaza, 2001 BCCA 133 and the judgment quotes from para. 15 of that decision: The third condition in the order is directed to the third party calling an independent medical examiner "for rebuttal evidence". I understand from counsel that this refers not to rebuttal evidence as generally understood, but to evidence that is purely responsive to medical evidence which the plaintiff has led as part of her case. It would not apply to opinion evidence offered by the third party on subject matters not adduced in the medical evidence adduced by the plaintiff.