dissenting.
The record in this case clearly indicates that the trial judge excluded Dr. Golden’s testimony regarding “brain injury” because no “medical doctors” had testified to such an injury. Thus, the exclusion was based on the judge’s belief that Dr. Golden was not qualified to render an opinion as to the presence of a brain injury in the plaintiff. I dissent from any suggestion created by the majority opinion that a neuropsychologist is not evidentially equipped, due to the lack of a medical degree, to render an expert opinion regarding the existence of a condition which is clinically known to produce a behavior disorder such as that seen in the plaintiff.
Obviously, plaintiff was attempting to prove that the accident caused certain disabling behavior changes which amounted to a compensable injury. Not all injuries are capable of producing observable physical manifestations. Physicians often must rely solely on a patient’s description of symptoms when making a diagnosis. This is equally true for psychologists, *501who must diagnose and treat emotional illnesses that they cannot see, hear, or touch. Yet these symptoms (pain, behavior changes, etc.) are real and often debilitating to a patient, both psychologically and physically.
I cannot agree with the majority’s conclusion that Dr. Golden’s opinion, because it was couched in alternatives, does not meet the required certainty standard. Dr. Golden was prepared to testify that one of only two probable causes existed to explain plaintiff’s behavior changes. Both of these causes related to a traumatic injury, and both would be compensable. This court noted in Marion v. American Smelting & Refining Co., 192 Neb. 457, 460, 222 N.W.2d 366, 368-69 (1974), that “it is impossible for a reputable doctor to testify with absolute certainty that one cause and one cause alone is the reason for [a] disability. Absolute certainty is not required. Medical diagnosis is not that exact a science.”
Plaintiff should not be denied adequate compensation simply because an alternative diagnosis cannot be ruled out as a probable causation factor. Dr. Golden’s opinion regarding a brain injury was not based on mere guess or conjecture. The opinion was based on facts ascertained from interviews, tests, and a medical history review, which ultimately resulted in a diagnosis based on the expertise of this witness. Any questioning of the basis for Dr. Golden’s opinion should go to its weight and credibility, not to its admissibility.
The lack of a medical degree should not be an automatic disqualification of an expert’s opinion. If the defendants wished to challenge the credibility or integrity of Dr. Golden’s opinion, the options of cross-examination and rebuttal expert witnesses are always available. I believe Dr. Golden’s testimony should have been allowed.
Hastings, C. J., joins in this dissent.