"Q. * * * [t]he methodology that you've employed in addressing questions for these 50 or so women, is all of that work based on generally accepted scientific principles and medical principles?  

"A. I believe so, yes.  

"Q. Is all of your examination technique based on standard neurological examination technique?  

"A. Yes.  

"Q. Is all of your sorting out and correlating and identifying of patterns and ruling out of other explanations based on standard medical and scientific principles?  

"A. Yes.  

"Q. So with respect to the route you've taken and the means you've used to get to your conclusions, you have no trouble saying that that is all based on accepted theory and technique?  

"A. No."  

After extensive discussion with counsel, the trial judge announced his ruling:  

"I don't have a problem with [plaintiff's] theory that [State v. O'Key, 321 Or 285, 899 P2d 663 (1995)] doesn't apply to medical doctors who are coming in and giving a diagnosis based on their specialty.  

"To the extent, however, that the diagnosis involves a new but unproven theory -- proven, that is, by the O'Key methods -- not necessarily because the doctor says. It's proven to him -- O'Key says let's check it out. Has there been peer review? Has there been a methodology compared to samples? Has there been an error study done, so we know at least there's a possibility of error? Just seeing the 43 out of 45 doesn't mean that it's an absolutely perfect study. * * *  

"[Grimm] can obviously say what he saw, and he can say that he's noticed a strong correlation between what he saw with [plaintiff] and what he has seen with some of his patients who have had silicone implants, multiple implants, and to that point I'm not seeing a serious problem. "As soon as he takes it a step further and it looks like to the jury that there is a disease out there called silicone-related disorder and she has it, I'm a little bit concerned, because I don't see the O'Key test met, particularly when the doctor talks in terms of correlation. When he says it's a condition, not a disease, and you are asking him causation and he's explained to me why it's a condition at this point, because he doesn't want to use the word 'disease' until he's further on in the studies -- " 

(Emphasis added.) At that point, counsel interrupted the judge and the judge did not complete his thought. The judge then continued:  

"[Grimm] can testify to his observations of symptoms in [plaintiff]. He did examine her. I'll certainly take his word that he did a history; that he does, in his clinical practice that is an accepted method, a thorough history, did it orally without using a questionnaire, but I have no reason to doubt his ability to do it or his statement that it's a history that is well-accepted within certainly the neurological community.  

"But he said he finds -- once he checked those symptoms out and because he's seen similar symptoms in 45 of his 10,000 patients, he sees a pattern, and the last women he saw have had silicone implants. He sees the correlation, a strong correlation between those two symptoms, the pattern of those two symptoms and women who have had -- or at least the 45 women who have had breast implants. "But that's as far as I think he can go. To say that it's a cause of a disease that's undefined -- well, it isn't even a disease. Dr. Grimm can't say it's a disease -- and he doesn't yet understand the mechanism. Someday he will, but he doesn't yet understand the mechanism. I just don't think he can go any further than that." 

(Emphasis added.)  

Plaintiff's counsel asked the judge whether Grimm could opine that, more probably than not, plaintiff's two symptoms were caused by silicone. The judge answered:  

"No, I don't think he can say that. I think he can say -- I think he can say what he did say. He did say in his diagnosis that there appears to be a strong correlation between women who have had silicone implants -- at least these last few women he's looked at -- women who have had silicone implants, there's a strong correlation, and these two symptoms, and he doesn't understand the mechanism of it, but between these symptoms, he's qualified to say that. That's what he did say. I don't have a problem with that.  

"But to stretch him and make it a causal -- use that word, 'There is such a thing as silicone-related disorder. I've examined [plaintiff] and she has silicone-related disorder based on my evaluations' -- I don't think he needs to go through the O'Key test as a medical doctor, but when he takes that one extra step and says, 'What I observed in the symptoms belongs to this category,' when he says, 'So far it's not a disease,' and so far he's still checking out things like error, peer review, things like that that still haven't happened, I think it would be inappropriate." 

(Emphasis added.)  

Plaintiff's counsel continued:  

"I think what Dr. Grimm can do, and maybe we didn't really get to this point clearly, you know, he can say, 'I see this correlation,' but then -- if in terms of what will -- then 'Do you think that silicone is causing [plaintiff's] case,' he would say that 'I put 25 or 30 possible causes on my differential, and I have systematically ruled them out and the only one that's left is silicone exposure.' And that, of course, makes it consistent with -- I mean, the correlation, then gives me the support. So there's actually two factors."  

The judge responded:  

"As long as we don't get to the point that anyone mentions the word 90 or 95 percent type of thing, because that's only with these 45 women. It's not with all of the patients he has seen who have had whatever. I don't want the jury to believe that somehow this is a magic number, because I'm pretty certain it isn't. 

"* * * * *

"At some point I don't mind getting the fact in front of the jury that I just mentioned, that small-level fact, and they can draw whatever inferences you argue to them or what they draw on their own. "What I don't want to have happened is placed for them as a fact, by way of opinion, that based on the preliminary methods and the preliminary work that Dr. Grimm has done so far, he's in it for the Nobel Prize, and discovered a new disease and she has it. "There may come someday where there are established epidemiological studies and enough experts that can tie this and somebody can say it's a cause. I'm just a little concerned -- I mean, if you say, to a reasonable medical probability or scientific probability, is there a correlation between what you observed in [plaintiff] and a response to silicone, or something of that nature, I think I could be comfortable with that. A correlation is what he said. You can still use the reasonable medical probability if he's talking as a doctor doctor, and I think he is, because if we say scientifically probable, we trigger O'Key." 

(Emphasis added.)  

Plaintiff's counsel continued:  

"[Grimm] is here, first and foremost, as a medical doctor."  

The judge responded:  

"Okay. So if you say, 'Doctor, to a reasonable medical probability, the symptoms that you have diagnosed in [plaintiff], you say to a reasonable medical probability there's a strong correlation between those symptoms and silicone' -- now, I may revise that in * * * a minute, but that sounds like something that I could deal with. He's not using the word 'cause,' he's not say[ing] 'the studies show' and he's not saying silicone-related disorders, but you said silicone exposure -- there's a strong correlation between the symptoms he's found and exposure to silicone, now that I think he can say, and I think * * * it will stand the test.  

"But if you get too much further out of that, I'm going to be real concerned, because I do see somewhere a bright line where we get beyond his medical diagnosis into where he's given a scientific opinion as to the fact of silicone-related disorder and a direct causation of that disorder when we're so preliminary at this point." 

(Emphasis added.)  

Plaintiff's counsel then asked:  

"What you're saying is he can say more probably than not there's a correlation, but he can't say more probably than not this is the cause --  

"THE COURT: Yeah. I think I could --  

"[Plaintiff's Counsel]: -- to a reasonable medical probability?  

"THE COURT: -- to a reasonable medical probability. And I would let you lead on that point so that we don't go jumping around." 

In response to a request by defense counsel for cross-examination, the trial judge stated, in part:  

"We've got a potential of an opinion crossing a discipline from medical into more or less a scientific certainty. I think we're stopping short of that, and I think it's all right."  

As noted, the jury returned a verdict for defendants, and the trial court entered judgment accordingly. Plaintiff appealed, assigning as error, inter alia, the trial court's ruling excluding Grimm's causation testimony. The Court of Appeals reviewed the trial court's ruling as a matter of law and concluded that the trial court erred when it excluded Grimm's opinion testimony about causation. Jennings, 152 Or App at 429. The court explained:  

"Whether Grimm's hypothesis is correct was a question of fact for the jury to decide in connection with the other evidence on the issue. In sum, we hold that Grimm's opinions meet the threshold requirement of logical relevance and that [defendant's] arguments go to the weight of the evidence and not to its admissibility. We conclude that the trial court erred when it excluded Grimm's opinion on causation.  

"* * * * *

"Without Grimm's testimony as to the causation for the neurological disorders, plaintiff may have been unable to effectively rebut [defendant's] theory of the case that she suffered from fibromyalgia. "In summary, the issue of causation was strongly contested throughout the trial with experts differing about whether the silicone that leaked from the implants was capable of causing plaintiff's complaints. The trial court's ruling effectively prevented plaintiff from offering testimony from a key witness about the issue of causation and that ruling may have affected the jury's view of the rest of plaintiff's evidence in light of the requirement that plaintiff had to prove her allegations by a preponderance of the evidence. On this record, we cannot say that there is 'little likelihood' that the trial court's ruling affected plaintiff's case, and we conclude that a new trial is necessary."  

Id. at 430-31.