Annotate this Case

2003 OK 10
65 P.3d 591
Case Number: 96813
Decided: 02/11/2003


DWAIN LEE CHRISTIAN, III, individually and as parent and next friend of MALORIE CHRISTIAN AND MICHAH CHRISTIAN, minors, Petitioners,



Mickey James and Andrew W. Gass, Green James & Williams, Oklahoma City, Oklahoma for Petitioners
Henry D. Hoss, Shawn E. Harrell, and Amy D. White, McAffee & Taft, Oklahoma City, Oklahoma for Real Party in Interest State Fair of Oklahoma, Inc.
Christian S. Huckaby, Looney, Nichols & Johnson, Oklahoma City, Oklahoma for Real Party in Interest City of Oklahoma City
Robert D. Looney, Jr., Hall, Estill, Hardwick, Gable, Golden & Nelson, Oklahoma City, Oklahoma for Real Party in Interest City of Oklahoma City
Rex K. Travis, Oklahoma City, Oklahoma (Thomas A. Wallace, Norman & Edem, Oklahoma City, of counsel on the brief) for Amicus Curiae Oklahoma Trial Lawyers Association
Karen M. Grundy & Jon Starr, Tulsa, Oklahoma for Amicus Curiae Oklahoma Association of Defense Counsel


¶1 The Christians brought suit in the District Court of Oklahoma County after they had attended a circus performance at the State Fair Arena in Oklahoma City. They alleged that they were injured by airborne chemicals they inhaled while attending the circus. The trial court ruled that Plaintiffs' expert witness was not competent to give a medical opinion on the cause of injury. We assume original jurisdiction on Plaintiffs' application, and issue a writ to the trial court with instructions to provide the parties an opportunity to present the determinative issues as we view them to be proper under the Daubert and Kumho cases.

I. Assuming Original Jurisdiction

¶2 Defendants filed a motion in limine to exclude the testimony of Plaintiffs' expert witness on the issue of the causation of Plaintiffs' injuries. The trial court granted the motion, and stated that the expert was not competent to give a medical opinion on the cause of Plaintiffs' injuries. The trial court relied upon Daubert v. Merrell Dowell Pharmaceuticals, Inc., 509 U.S. 579, 113 S. Ct. 2786, 125 L. Ed. 2d 469 (1993), and Kumho Tire Co., Ltd. v. Patrick Carmichael et al., [65 P.3d 594] 526 U.S. 137, 119 S. Ct. 1167, 143 L. Ed. 2d 238 (1999). This Court has not previously determined whether Daubert and its progeny apply to civil proceedings in this State. 1 Several states have adopted or use Daubert when determining admissibility of an expert's opinion. 2[65 P.3d 595]

¶3 By previous order of the Court this controversy was recast from a proceeding seeking certiorari of an interlocutory order to an application for extraordinary relief and assumption of original jurisdiction. This matter is one of first impression. Recasting such a proceeding is procedurally proper,

II. Daubert and its Progeny

¶4 Plaintiffs alleged that they were injured by airborne chemicals that they inhaled while attending a circus in the State Fair Arena. Defendants filed a motion in limine to exclude the testimony, opinions, and exhibits of Plaintiffs' expert on the issue of the causation of Plaintiffs' injuries. The trial court granted the motion, stating that plaintiffs' expert "is not competent to give a medical opinion on the cause of injury based upon the test set forth in Daubert v. Merrell Dowell Pharmaceuticals, Inc.,

¶5 In Oklahoma the testimony of an expert is controlled by the applicable statutes found in the Oklahoma Evidence Code, 12 O.S.2001 § 2702 (Testimony by Experts);

¶6 Professor Whinery has explained that § 2702 is "identical in substance" to Federal Rule 702, §§ 2703 and 2704 are identical to Rules 703 and 704, and § 2705 has slightly different language than that in Rule 705 but "[t]here is no indication that the Legislature intended a substantive change" by the modification. 1 L. Whinery, Evidence, at 238, 243, 247, 255. We have said that federal court decisions may be examined for persuasive value when they construe federal evidence rules with language substantially similar to that in our evidence statutes. Willoughby v. Oklahoma City,

¶7 In Daubert the Court observed that the previously used general-acceptance test in Frye v. United States, 54 App.D.C. 46, 47, 293 F. 1013 (1923), for the admissibility of scientific evidence had been displaced by the Federal Rules of Evidence. The Court explained that Federal Rules imposed certain limits on the admissibility of such evidence. The Court also explained the trial judge's role in applying these limits. First, the trial judge examines the relevance and reliability of the evidence : "under the Rules the trial judge must ensure that any and all scientific testimony or evidence admitted is not only relevant, but must be 'scientific' and reliable." Daubert,

¶8 Daubert

¶9 The evidence must also "assist the trier of fact to understand the evidence or to determine a fact in issue." This requirement "goes primarily to relevance." Daubert,

The Court then explained the trial judge's role:

Faced with a proffer of expert scientific testimony, then, the trial judge must determine at the outset, pursuant to Rule 104(a), whether the expert is proposing to testify to (1) scientific knowledge that (2) will assist the trier of fact to understand or determine a fact in issue. This entails a preliminary assessment of whether the reasoning or methodology underlying the testimony is scientifically valid and of whether that reasoning or methodology properly can be applied to the facts in issue. We are confident that federal judges possess the capacity to undertake this review. Many factors will bear on the inquiry, and we do not presume to set out a definitive checklist or test.


§ 2105. Preliminary questions
A. Preliminary questions concerning the qualifications of a person to be a witness, the existence of a privilege or the admissibility of evidence shall be determined by the court, subject to the provisions of subsections B and C of this section.
B. A person claiming a privilege must prove that the conditions prerequisite to the existence of the privilege are more probably true than not. A person claiming an exception to a privilege must prove that the conditions prerequisite to the applicability of the exception are more probably true than not. If there is a factual basis to support a good faith belief that a review of the allegedly privileged material is necessary, the court, in making its determination, may review the material outside the presence of any other person.
C. When the relevancy of evidence depends upon the fulfillment of a condition of fact, the judge shall admit it upon, or subject to, the introduction of evidence sufficient to support a finding of the fulfillment of the condition.
D. Hearings on the admissibility of confessions shall be conducted in all cases out of the hearing of the jury. Hearings on other preliminary matters shall also be conducted out of the hearing of the jury when the interests of justice require or when requested by an accused who is a witness.
E. The accused does not subject himself to cross- examination on other issues in the case by testifying upon a preliminary matter.
F. This section does not limit the right of a party to introduce before the jury evidence relevant to weight or credibility.
12 O.S.Supp.2002 § 2105 .

Thus a trial judge's decision to prevent improper testimony from an expert witness is [65 P.3d 598] not new to our jurisprudence.

¶10 The High Court thereafter decided Kumho Tire Co. v. Carmichael,

¶11 The High Court has stated that a trial court must make a determination of the reliability of an expert's evidence when it is sufficiently challenged.

And where such testimony's factual basis, data, principles, methods, or their application are called sufficiently into question, . . . the trial judge must determine whether the testimony has "a reliable basis in the knowledge and experience of [the relevant] discipline."
Kumho Tire Co., Ltd. v. Carmichael,

In Daubert the Court indicated that this reliability determination is not limited to novel or "unconventional" evidence.

Although the Frye decision itself focused exclusively on "novel" scientific techniques, we do not read the requirements of Rule 702 to apply specially or exclusively to unconventional evidence. Of course, well-established propositions are less likely to be challenged than those that are novel, and they are more handily defended. Indeed, theories that are so firmly established as to have attained the status of scientific law, such as the laws of thermodynamics, properly are subject to judicial notice under Federal Rule of Evidence 201.
Daubert v. Merrell Dow Pharmaceuticals, Inc.,

Our Court of Criminal Appeals has determined that Daubert shall apply to novel scientific evidence in criminal proceedings. Taylor v. State,

¶12 Plaintiffs assert by brief in this Court that Daubert applies to only novel evidence. We have no record before us showing argument in the trial court by Plaintiffs that the methods of their expert showed a facial reliability for the type of conclusion the expert made. On the other hand, Defendants' argument presupposes the absence of such reliability and that a Daubert proceeding is necessary. We decline to address further this argument, except as it pertains to the issue of causation discussed later in this opinion. This issue we leave to the parties to address in the trial court upon conclusion of this extraordinary proceeding.

¶13 In Kumho Tire Co., supra, the Court explained that a trial court has some latitude in applying the Daubert factors of reliability: "Thus, whether Daubert's specific factors are, or are not, reasonable measures of reliability in a particular case is a matter that the law grants the trial judge broad latitude to determine." Kumho,

The Daubert factors "may" bear on a judge's gatekeeping determinations, however. The four Daubert factors "'may or may not be pertinent'"; it will all depend ''on the nature of the issue, the expert's particular expertise, and the subject of his testimony.'" Determining which factors are indicative of reliability in a particular case cannot be accomplished solely by a categorical a priori characterizations about the particular field in question. The Court explained: "Engineering testimony rests upon scientific foundations, the reliability of which will be at issue in some cases. . . . In other cases, the relevant reliability concerns may focus upon personal knowledge or experience." In all cases, a court must exercise its gatekeeping obligation so that the expert, whether relying on "professional studies or personal experience," will, when testifying, employ "the same level of intellectual rigor" that the expert would use outside the courtroom when working in the relevant discipline.
Federal Judicial Center, Reference Manual on Scientific Evidence, 19 (2d ed.2000), quoting, Kumho, supra.

A trial court must thus make a determination of the appropriate factors of reliability for the particular controversy before it based upon the nature of that controversy.

¶14 Nothing in Daubert or Kumho conflicts with our Evidence Code. Our Court of Criminal Appeals has already adopted Daubert for criminal proceedings in Oklahoma Courts. Today we likewise adopt Daubert and Kumho as appropriate standards for Oklahoma trial courts in deciding the admissibility of expert testimony in civil matters.

III. Causation

¶15 This proceeding is not an appeal, but a challenge to a District Court's order in an action independent to the one before the trial court, and we examine the arguments presented to the trial court and appearing in the record prepared for us by the parties. We thus decline to consider the affidavit of Plaintiff's expert signed and filed herein approximately two months after the decision of the trial court.

¶16 The medical doctor testified in his deposition that one of the Plaintiffs had permanent impairment in his breathing ability. He testified that he did not have any tests of plaintiff's breathing ability before he attended the circus, that Plaintiff's impairment was a restrictive lung disease, and that restrictive lung impairments could be caused from a variety of sources. He stated that he took into account the previous sinus problems of the Plaintiff, and that such problems would not cause the type of permanent lung impairment suffered. He also stated that viral infection could not have caused the impairment, and that there was no evidence of bacterial infection. He stated that he did not "know exactly what was there in the air" in the arena on the day of the circus and that he could not state the exact cause of the impairment. He stated that Plaintiff's exposure to lime in the form of an inhalant could have caused the lung impairment. He stated that his opinion, with a reasonable degree of medical certainty, was that "lime exposure or some other type of inhalant that they were exposed to at that time has caused their lung damage."

¶17 Defendants focused their questions to the doctor on his knowledge of lime. He stated that he had seen some lime exposure cases resulting in a "lime burn" on patients "but that's not what we're dealing with here." He testified that he knew of no studies on airborne lime exposure, or any studies linking exposure of airborne lime to respiratory impairments. He stated that he was not a specialist in toxic chemistry, environmental chemistry, or a pulmonologist. He stated that he did not know the type of cement used at the State Fair Arena, or the percentage of lime used. He stated that he was not familiar with how lime travels through the air, or how long it remains airborne. He stated that he was not aware of the quantity of airborne lime at the time of the circus.

¶18 The doctor further stated that Plaintiffs' symptoms could have been caused by a "number of things" that could have been airborne. "The only thing that I can give a reasonable, you know, degree of medical certainty is that perhaps the lime exposure or some other type of inhalant that they were exposed to at that time has caused their lung impairment." He stated that he would tell the jury that "I'm going to say from their history and from what I have seen, it's possible that this could be caused from some exposure to chemicals. What chemicals and is it Lime? I don't know." He further testified that a "big-time allergy" could cause the impairment, and that the allergic reaction could be caused by pollens, grasses, and dust in general. In sum, the doctor testified that Plaintiffs' permanent restrictive lung impairment was a type that is observed after exposure to certain materials as inhalants, and that lime could have been one of these materials.

¶19 Plaintiffs also produced for the trial court an analysis of samples of material collected from the State Fair Grounds Arena eighteen days after the circus. That report contains the following:

. . . Visual observation showed considerable fine material which could certainly become airborne with foot traffic. We checked the pH on a 1:1 paste and found the pH to be 11.53 - a highly alkaline material The sample was subjected to Scanning Electron Microscopy . . . [t]he results for sample A are consistent with the sample being comprised of a mixture of sand (SiO2) and lime (CaO or Ca(OH)2).

Defendants challenged this report in the trial court, and argued that the person who collected the white powder could not testify whether it was in the air eighteen days earlier at the time of the circus.

¶20 The doctor, a medical professional, was asked to give an opinion as an expert on the issue of the cause of Plaintiffs' medical injuries. When an injury is of a nature requiring a skilled and professional person to determine cause and the extent thereof, the scientific question presented must necessarily be determined by testimony of skilled and [65 P.3d 601] professional persons.

¶21 Causation is now often divided into general causation and specific causation in some controversies involving allegations of injury resulting from a person's exposure to a harmful substance. General causation is whether a substance is capable of causing a particular injury or condition in the general population, while specific causation is whether that substance caused the particular individual's injury.

¶22 The doctor stated that Plaintiffs' injuries resulted from inhalation of certain types of chemicals, and that lime is such a chemical. The trial court order states that the doctor "does not know of any studies linking lime exposure with respiratory impairment." This language in the trial court's order links showing general causation with certain types of published studies, i.e., studies specifically on lime. Studies on lime in similar circumstances would be beneficial to show causation; however, we find nothing in the record stating that this is only method of showing causation. Defendants' focus on the absence of studies of airborne lime in the doctor's testimony fails to provide for the possibility that lime has certain physical properties that are shared with other chemical substances that have been subjected to studies, and that this method was used by the doctor to reach his conclusion. The doctor's testimony on causation discussed types of chemicals and included lime. However, no testimony of the doctor is before us showing how the doctor linked lime to other chemicals and the specific injury of Plaintiffs. Plaintiffs failed to state, by published studies or otherwise, the nature of similarity between lime and other chemicals relevant to causation. Plaintiffs did not try to link the degree of the toxicity of lime with scientific or medical evidence to show how lime, as an alleged toxic substance, could have caused the particular injury. In other words, Plaintiffs did not try to identify a mechanism by which their alleged chemical exposure led to the putative effect. Thus, we are not called upon in this controversy to decide what types of scientific reasoning or methods are acceptable for showing legal causation.

¶23 Our Evidence Code points to the respective burdens of parties when admissibility of evidence is challenged.

§ 2104. Rulings on Evidence
A. Error may not be predicated upon a ruling which admits or excludes evidence unless a substantial right of a party is affected, and:
1. If the ruling is one admitting evidence, a timely objection or motion to strike appears of record, stating the specific ground of objection, if the specific ground was not apparent from the context; or
2. If the ruling is one excluding evidence, the substance of the evidence was made known to the judge by offer or was apparent from the context within which questions were asked.

In one context we have said that the burden of showing that a statement offered in evidence is admissible is upon the party offering it. Wofford v. Lewis,

¶24 The Kansas Supreme Court has concluded that some cases are not appropriate for imposing a general causation requirement. Kuhn v. Sandoz Pharmaceuticals Corp., 270 Kan. 443, 14 P.3d 1170 (2000). That court stated the following.

We do not foreclose, by our holding here, that a future case with appropriate facts may require a finding of general and special causation. However, the facts here distinguish this case from cases that have employed a general causation requirement. First, general causation requirements (requiring plaintiffs to present confirming epidemiological evidence to make out a prima facie case) have typically been applied in cases involving mass exposures:
"Cases that have not imposed this requirement [general causation] typically involve injuries that may be placed in the 'sporadic accident model of tort law.' In [these] cases, where only a single plaintiff or a few plaintiffs have allegedly suffered an injury due to some exposure, a medical doctor will be permitted to render an opinion as to whether the exposure caused the plaintiff's injury solely on an examination of the plaintiff and a differential diagnosis of the source of the plaintiff's injury, sometimes supplemented with toxicological evidence.... "
"In many of these cases there is relatively little epidemiological data available and the courts are reluctant to burden 'first plaintiffs' with the task of using epidemiology to prove general causation." 2 Faigman, Keye, Saks & Sanders, Modern Scientific Evidence: The Law and Science of Expert Testimony: The Role of Epidemiological Evidence in Toxic Tort Cases. § 28-1.3.2, pp. 307-08 (Citing Boston, A Mass Exposure Model of Toxic Causation: The Content of Scientific Proof and the Regulatory Experience, 18 Colum.J.Envtl. L. 181, 188 [1993].)

The scope of plaintiffs' case here does not approach that of mass tort litigation. [65 P.3d 603] In addition, general causation requirements are usually imposed in cases with large existing epidemiological records. Richardson v. Richardson-Merrell, Inc.,

The Kansas court examined whether the alleged exposure was in a circumstance involving a "mass exposure" or a "sporadic accident model of tort law" involving a single plaintiff or a few plaintiffs. That court also discussed whether epidemiological

¶25 The trial court record before us does not show any argument specifically identifying the issues of general causation, specific causation, nor application of each to this controversy. Further, although the brief of Defendants raises the issue, there is no discussion of why its application to lime is appropriate either as an issue of fact or law. The Kansas court discussed the application of a general causation requirement as dependent upon certain facts. In this extraordinary writ proceeding we do not have a complete record of facts relating to this controversy.

¶26 Not all courts have agreed that Daubert requires the same type of methodology for general causation in all circumstances. See, e.g., Heller v. Shaw Industries, Inc.,

¶27 What have the courts had to say about specific causation? Two issues often discussed are (1) the appropriateness of a differential diagnosis, and (2) the temporal, or time-based, relationship between the exposure and a plaintiff's injury.

¶28 "Differential diagnosis, or differential etiology, is a standard scientific technique which identifies the cause of a medical problem by eliminating the likely causes until the most probable one is isolated. . . . A reliable differential diagnosis typically is performed after 'physical examinations, the taking of medical histories, and the review of clinical tests, including laboratory tests,' and generally is accomplished by de-[65 P.3d 604]-termining the possible causes for the patient's symptoms and then eliminating each of these potential causes until reaching one that cannot be ruled out, or determining which of those that cannot be excluded is the most likely." Magistrini v. One Hour Martinizing Dry Cleaning, 180 F. Supp. 2d 584, 609 ( D.N.J. 2002), (citation omitted). Courts have not been uniform in applying Daubert when assessing the methodology of clinical medicine to prove causation.

¶29 In Oklahoma a physician treating a patient may use a medical history provided by the patient when making an opinion on causation of the patient's injury. In Sneed v. Beaverson,

. . . [T]he correct rule, it would appear, should permit a physician to testify to a statement or narrative given him by his patient in relation to his condition, symptoms, sensations, and feelings, both past and present, when made in connection with his own opinion as to the cause of the injury, though the statement may not be received as independent evidence to establish the fact of the injury.

A physician using a patient's history is part of a method to determine causation of an injury. See A & A Checker Cab Operating Co. v. Fritzshall,

¶30 The trial court order before us today does not refer to the medical history of one of the Plaintiffs, or their testimony, or the report on the substance found at the arena. The doctor testified that he relied upon a medical history of one of the Plaintiffs. Plaintiff said that he saw things falling from the ceiling "like a cloud" and the doctor based his opinion upon this history and the time-based relationship between Plaintiffs' presence at the circus and the onset of symptoms. The trial court agreed with Defendants that Plaintiffs' expert was required to show both the quantity of airborne lime necessary to cause injury (general causation) and the actual amount of airborne lime present (specific causation) the day Plaintiff attended the circus. The trial court made no specific findings on whether the doctor's method of using the medical history, testimony of plaintiff, and report of the other expert was a proper method for determining medical causation.

¶31 Not all courts have agreed that Daubert requires the expert to actually measure the substance in the air before testifying on causation. For example, in Harris v. Peridot Chemical (New Jersey), Inc., 313 N.J.Super. 257, 712 A.2d 1181 (App.Div.1998), that court explained that when a expert showed a defect in equipment causing a release of the toxic substances, and that plaintiffs' injures were consistent with exposure to the substances, the opinion testimony on causation was "'based on a sound, adequately-founded scientific methodology involving data and information of the type reasonably relied on by experts in the scientific field.'" Id. 712 A.2d at 1201.

¶32 Further, Defendants' argument herein requiring an actual measurement of the airborne lime at the time of the circus results [65 P.3d 605] in an approach that would prevent many lawsuits based upon a single-event exposure, such as, for example, when a plaintiff brings an action and testifies of being enveloped by a great cloud of noxious gas from a calamitous event occurring in the absence of an expert. See, e.g., Louisville and Nashville R. Co. v. Hickman, 445 So. 2d 1023 (Fla. 1

¶33 We do not agree, upon this record, that actual measurement of the airborne particles at the circus was necessary for the toxic exposure case. One the other hand, we can not state upon this record, what other particular method would be appropriate for the particular substance in this case. The methods of quantifying this particular substance and the relationship between quantity of substance and onset of injury must be addressed in the trial court by the parties.

¶34 A plaintiff may testify that he or she was overcome by gas or fumes that are felt, seen, or smelled by the plaintiff. For example, in Mid-Continent Petroleum Corp. v. Epley,

¶35 This action today is based upon the allegation that exposure of Plaintiffs to a particular substance caused injuries. This means that a plaintiff must show such exposure and that such exposure caused the injury. One court has stated that "A widely accepted toxicological methodology for determining the possible effects of a toxin on humans requires: '"[F]irst[,] that the expert determine the dosage of the toxin at issue to which the plaintiff was exposed...." Plourde v. Gladstone, 190 F. Supp. 2d 708, 721 (D.Vt. 2002). The method for determining the level of the toxin present in the environment may vary, and may include, when appropriate, the observations of those non-experts present when the exposure occurs. The dosage of the toxin necessary to cause injury may be relatively small, but some fact as to the dosage necessary for causing injury must usually be included by the expert when making an opinion on general causation. Plaintiffs' expert in the case before us today failed to specifically explain a method for determining the amount of lime that could result in injury, and failed to explain a method (whether by direct observations of others or otherwise) for an opinion that the lime present was in sufficient quantities to cause Plaintiffs' injuries in this case.

¶36 The sufficiency of an expert's evidence to support a conclusion is distinct from the reliability of the method used by the expert. [65 P.3d 606] However, the U. S. Supreme Court has not maintained a sharp distinction between the reliability of an expert's methods and conclusions. That Court has allowed courts to determine the validity of an expert's conclusion. In General Electric Co. v. Joiner,

But conclusions and methodology are not entirely distinct from one another. Trained experts commonly extrapolate from existing data. But nothing in either Daubert or the Federal Rules of Evidence requires a district court to admit opinion evidence that is connected to existing data only by the ipse dixit of the expert. A court may conclude that there is simply too great an analytical gap between the data and the opinion proffered. See Turpin v. Merrell Dow Pharmaceuticals, Inc.,

An expert's opinion on causation must be more than ipse dixit.

¶37 At the trial court hearing Plaintiffs focused upon what the doctor did know, e.g., spirometry, medical history, symptoms, etc., and the conclusion of the doctor. Defendants focused on what the doctor did not know, such as quantity of airborne lime, if any, at the time of the circus, published studies on airborne lime, and his opinion on possible alternative causes for Plaintiffs' symptoms. The trial court focused on what the doctor did not know and concluded from this that the doctor could not say with a reasonable degree of medical certainty whether Plaintiffs' exposure caused the injuries. The trial court statement is not completely clear whether the court is making a determination that the unknown facts are necessary as part of a proper method for determining toxic exposure, or that the expert's conclusion is analytically unsound based upon what he does know, or that the expert's opinion is not admissible for flaws in both method and conclusions. We construe the order as concluding that both method and conclusions were improper.

¶38 In summary on the issue of causation, assuming that the expert's method for his conclusions is novel and reliability cannot be taken for granted, we hold that if expert testimony is necessary to show cause of an injury from exposure to a toxin, the testimony of the expert should reveal a reliable method for determining the quantity of the toxin necessary to cause injuries of the type experienced by plaintiff (general causation), unless plaintiff can show that the circumstances are such that general causation should not be necessary. See, e.g., Kuhn v. Sandoz Pharmaceuticals Corp., supra. Further, the expert's conclusion must be analytically appropriate for the expert's method.

IV. Standard of Review

¶39 A Daubert challenge is primarily one to the reliability of expert evidence. Daubert provided a list, set out above, of four non-exhaustive factors for the trial judge to consider when determining the admissibility of [65 P.3d 607] evidence. The trial court order does not expressly address whether any of these four factors, or any other factor, is relevant to a method for showing causation for this particular alleged injury.

¶40 Generally, an adjudication determining the proper legal procedure for a particular controversy presents an issue of law, and is reviewed by a non-deferential de novo standard. In re A.M.,

¶41 An issue of law decided by a trial court is reviewed by this Court de novo. Brown v. Nicholson,

¶42 First, the clear abuse of discretion appellate standard applies when we review a decision on the admissibility of expert testimony. In the context of a ruling on the relevance of proffered evidence we have said that "a judgment will not be reversed based on a trial judge's ruling to admit or exclude evidence absent a clear abuse of discretion." Myers v. Missouri Pacific R. Co.,

¶43 Secondly, a clear abuse of discretion standard includes appellate review of both fact and law issues: "In order to determine whether there was an abuse of discretion, a review of the facts and the law is essential." Board of Regents of University of Oklahoma v. National Collegiate Athletic Association,

¶44 Abuse of discretion review may also include a review of facts (evidence). "An abused judicial discretion is manifested when discretion is exercised to an end or purpose not justified by, and clearly against, reason and evidence. It is discretion employed on untenable grounds or for untenable reasons, or a discretionary act which is manifestly unreasonable." Patel v. OMH Medical Center, Inc.,

¶45 When we speak of the discretion of the trial judge we do not mean that the decision of the trial judge is one without fixed principles by which its correctness may be determined upon appellate review. See Hofer, Standards of Review - Looking Beyond The Labels, 74 Marq. L. Rev. 231, 246-247 (1991), (application of some discretion-based standards are sufficiently open-ended so as to allow more than one "correct" decision upon the same set of facts). It is certainly true that pursuant to Daubert a trial judge possesses the discretion to determine, based upon facts presented to the trial court, that a factor, other than one of the four Daubert factors, is appropriate to measure the reliability of a particular expert witness. But the exercise of discretion making that determination must be based upon a fact of record showing that reliability is predicated upon the presence of that factor used by the trial court. Further, when reliability turns on an issue of law, as we explain below, a trial court is not free to ignore relevant and binding precedent on that issue. Issues of fact and law decided by the exercise of the judge's discretion are subject to appellate review.

¶46 The trial judge is called upon to decide issues of fact. The four non-exhaustive Daubert factors: (1) Can, or has, the expert's method been tested; (2) Has the expert's method been subjected to peer review and publication, (3) Is there a known or potential rate of error and the existence of standards controlling the method, and (4) Is there widespread acceptance of the method within the relevant community of experts - all involve determination of facts. A trial court's determination of those facts is subject to appellate review - is the determination against reason and evidence - is it an abuse of discretion? The trial court record before us is not specific on application of these Daubert factors or other factors determined by the trial court to be appropriate for Plaintiffs' expert.

¶47 In State ex rel. Burk v. City of Oklahoma City,

¶48 In our case today the Daubert issue was raised by motions in limine.

¶49 In our case today, the trial court attempted to apply Daubert, and one stated reason for the trial court rejecting the expert's conclusion was because the expert did not possess "baseline data" of Plaintiffs' pulmonary functions prior to Plaintiffs' exposure at the circus. The requirement of baseline data was put forward by argument of counsel for Defendant and adopted by the trial court. Is possession of "baseline data" required by the relevant community of experts in order to make a conclusion such as that made by a plaintiff's expert? Here, Plaintiffs' expert stated that a pre-circus spirometry "would be very helpful," but he did not testify that it was necessary for his conclusion. If that type of medical test is considered necessary by the relevant experts for the conclusion on causation made by a plaintiff's expert, then the evidence presented should reflect such and the order should state such finding of fact.

¶50 On the other hand, trial courts may determine that a particular fact is necessary to show causation and the ruling presents a question of law. In McKellips v. Saint Francis Hosp., Inc.,

Proximate cause consists of two elements: cause in fact and legal causation. Legal causation concerns a determination whether legal liability should be imposed as a matter of law where cause in fact is established and depends upon considerations of common sense and policy. Cause in fact, on the other hand, deals with the "but for" consequences of an act. "The defendant's conduct is a cause of the event if the event would not have occurred but for that conduct." The present matter involves only the question whether appellees or the decedent's underlying condition was the real cause--cause in fact--of his death. Therefore, our opinion does not deal with the scope of proximate cause involved in the concept of legal causation. Generally, the question of cause in fact is for the jury. It is only when there is no evidence from which the jury could reasonably find a causal nexus between the negligent act and the resulting injury it becomes a question of law for the court.

[65 P.3d 610]
The sufficiency of the evidence to show cause in fact presents a question of law for the court. Sufficiency of evidence is the "legal standard which is applied to determine whether the case may go to the jury." A plaintiff's burden of proof of causation is twofold. First, a plaintiff has the burden of producing evidence, satisfactory to the judge, that a reasonable person could believe in the existence of the causal link and that the evidence should be weighed by the jury. A verdict will be directed for the defendant if a plaintiff fails to carry this burden. Secondly, a plaintiff bears the burden of persuasion should the evidence be allowed to reach the jury. The standard for sufficiency of proof of evidence, related to a plaintiff's first burden, should not be confused with the standard of proof, associated with a plaintiff's second burden, which is applied by the jury in reaching a final verdict. Generally, in civil cases the standard of proof means a preponderance of the evidence. The certified questions concern the burden of production and sufficiency of proof of causation standard as to whether the causation issue should be submitted to the jury.
McKellips v. Saint Francis Hosp., Inc., ¶¶ 9-10,

When a trial court determines that the facts are insufficient to show cause in fact because a reasonable person could not believe in the existence of the causal link between the injury and facts relating to a defendant's conduct, then the trial court is deciding an issue of law, i.e., what a reasonable person believes, and a de novo standard will apply. Here the trial court listed several facts that the expert did not know, and then concluded that the expert did not show causation, and that his testimony was thus inadmissible. The conclusion of the trial court, although not expressly stated as such, was a legal determination - a conclusion that the facts were insufficient to show cause in fact to a reasonable person. This concept is not new. Trial courts frequently determine causation issues in the context of motions for directed verdicts, and we review those using a de novo standard.

¶51 In Weisgram v. Marley Co.,

Inadmissible evidence contributes nothing to a "legally sufficient evidentiary basis." See Brooke Group Ltd. v. Brown & Williamson Tobacco Corp.,

In sum, an expert opinion may be not supported by sufficient facts for legal validation because of at least one of two reasons, (1) It is without, or not based upon, facts necessary for the method or technique used by the expert, or (2) The facts do not support the conclusion of the expert. The abuse of discretion standard applies when reviewing both reasons, and that standard requires us to determine whether a trial court is determining a fact or an issue of law. Once we identify whether fact or law has been adjudicated by the trial court, we then must determine if a deferential or a non-deferential de novo review applies to the particular adjudication of fact, and to an issue of law we apply a non-deferential de novo standard.

¶52 Defendant argues that the trial court order should not be disturbed absent an abuse of a discretion. We agree with that standard, but not with the application of Defendant. The trial court stated that it was applying Daubert, but it abused its discretion, on this record, in making a [65 P.3d 611] determination that a base-line (pre-injury) pulmonary function study, such as a spirometry, was necessary to show cause in fact of an alleged pulmonary injury from airborne lime at the circus. No fact was before the trial court showing that such test was considered to be necessary by the relevant community of experts, or by satisfaction of any of the other Daubert factors. We have said that a trial court commits an abuse of discretion when it decides an issue based upon a fact not of record. Pickett v. Chicago, R.I. & P. Ry. Co., supra. Further, to the extent that the trial court made a determination of the necessity of a base-line study to support the expert's conclusion, as a matter of law, i.e., that a reasonable person could not believe in the existence of the causal link in the absence of such study, we review that determination de novo, and note that no legal authority is cited by Defendants in support of the necessity of a base-line (pre-injury) medical study to show cause in fact of a medical injury.

V. Conclusion

¶53 We conclude that Oklahoma courts should apply Daubert and Kumho as we have applied them here when determining the admissibility of an expert's opinion. Plaintiffs in this case must be allowed an opportunity to make the required showing pursuant to Daubert, and Defendants an opportunity to challenge that testimony, according to the standards we have now articulated.

¶54 The trial court did not determine that the methods of Plaintiffs' expert were insufficient pursuant to one of the particular Daubert factors, or some other factor determined to be appropriate in applying Daubert. The trial court challenged the expert's conclusion, but did not specifically link a deficient conclusion with either a faulty method or an exercise of ipse dixit by the expert. We hereby issue a writ of prohibition and the order of the trial court shall not be enforced. However, we do not determine that the testimony of Plaintiffs' witness satisfies Daubert. We stated herein that upon Defendants' specific challenge to Plaintiffs' expert on the basis of general causation, Plaintiffs had a burden of either showing general causation or showing that general causation is not necessary for the admissibility of the particular expert's testimony. Plaintiffs have this opportunity upon conclusion of this proceeding.

¶55 Application of the standard of review in this Court requires identifying whether the trial court made determinations of fact or law, and our opinion provides an example where the trial court abused its discretion upon the record now before us. The parties have a responsibility of framing the issues for the trial court and identifying controverted issues as either fact or law. Whether the trial court abused its discretion in other particulars we need not address, because the issue of the admissibility of the testimony by Plaintiffs' expert is left open for further proceedings in the trial court. In sum, the writ is issued and the order shall not be enforced, but the parties may now litigate the admissibility of the expert testimony based upon the Daubert criteria as we have explained herein.


¶57 OPALA, V.C.J., - Concurs in part, dissents in part

¶58 HARGRAVE, J. - Dissents [65 P.3d 612]


1 In Cities Service Co. v. Gulf Oil Corp, 1999 OK 14, ¶ 32, 980 P.2d 116, 132, we cited Daubert for the proposition that a trial judge has the role of a gatekeeper to screen evidence by determining its relevance and reliability. Id. at n. 68. We did not address the Daubert standard.

2 One writer has stated that forty-six states have adopted Rule 702, thirty-three states have adopted Daubert, and several have not yet considered whether to adopt Daubert. See Note, The Movement From Frye to Daubert: Where Do the States Stand?, 38 Jurimetrics J. 201, 208-09 (1998).
In addition to the Oklahoma Court of Criminal Appeals, we have found courts in eighteen states that currently have adopted Daubert. See, e.g., Turner v. State, 746 So. 2d 355, 358 - 360 (Ala.1998); State v. Coon, 974 P.2d 386, 389-391 (Alaska 1999); Farm Bureau Mut. Ins. Co. of Ark., Inc. v. Foote, 341 Ark. 105, 14 S.W.3d 512, 519-520 (2000); State v. Porter, 241 Conn. 57, 698 A.2d 739 (1997); M.G. Bancorp., Inc. v. Le Beau, 737 A.2d 513, 522 (Del. 1999); Rogers v. Commonwealth, 86 S.W.3d 29, 42 (Ky. 2002); Independent Fire Ins. Co. v. Sunbeam Corp., 1999-2181, 755 So. 2d 226, 235 (La.2000); State v. Cline, (1996), 275 Mont. 46, 909 P.2d 1171, 1177; Schafersman v. Agland Coop, 262 Neb. 215, 631 N.W.2d 862, 876-877 (2001); State v. Alberico, 861 P.2d 192, 203 (N.M. 1993); State v. Goode, 461 S.E.2d 631, 639 (N.C. 1995); State v. Sampson, 167 Or.App. 489, 6 P.3d 543, 551 n.9, rev. den., 331 Or. 361, 19 P.3d 354 (2000), Raimbeault v. Takeuchi Mfg. (U.S.), Ltd., 772 A.2d 1056, 1061 (R.I. 2001); Boomsma v. Dakota, Minnesota & Eastern R.R. Corp., 2002 SD 106, 651 N.W.2d 238, 247, citing, State v. Hofer, 512 N.W.2d 482, 484 (S.D.1994); E.I. duPont de Nemours and Co. v. Robinson, 923 S.W.2d 549, 556 (Tex. 1995); State v. Streich, 163 Vt. 331, 658 A.2d 38, 46 (1995); Wilt v. Buracker, 191 W.Va. 39, 443 S.E.2d 196 (1993), cert. denied, 511 U.S. 1129, 114 S. Ct. 2137, 128 L. Ed. 2d 867 (1994); Bunting v. Jamieson, 984 P.2d 467 (Wyo.1999). New Hampshire recently adopted Daubert in Baker Valley Lumber, Inc. v. Ingersoll Rand Co., __ N.H. __, ___ A.2d ___, 2002 WL 31780239 (Dec. 12, 2002).
Courts in an additional eight states have stated that Daubert is instructive for application of the relevant state statute. State v. Vliet, 95 Hawaii 94, 19 P.3d 42, 53 (2001), (Hawaii has neither accepted or rejected Daubert, but because the Hawaii statute is patterned on the federal rule construction of that rule by the federal courts is instructive); Hyppolite v. State, 774 N.E.2d 584, *601 (Ind.App.2002), ("although not binding upon the determination of the state evidentiary law issues, the federal evidence law of Daubert and its progeny is helpful to the bench and bar in applying the Indiana Rule of Evidence"); In re Detention of Holtz, 653 N.W.2d 613, 615 - 616 (Iowa App.2002),("trial courts are not required to apply the analysis set forth in Daubert . . . in considering the admission of expert testimony . . . [but] trial courts may find it helpful in complex cases to use one or more of the relevant Daubert considerations in assessing the reliability of expert testimony"), quoting, Leaf v. Goodyear Tire & Rubber Co., 590 N.W.2d 525, 532 (Iowa 1999), (adopting a limited application of Daubert); Commonwealth v. Lanigan, 419 Mass. 15, 641 N.E.2d 1342, 1349 (Mass.1994), (accepted the basic reasoning of Daubert); State v. Stevens, 78 S.W.3d 817, 832 - 834 (a trial court may consider the factors listed in Daubert) McDaniel v. CSX Transportation, Inc., 955 S.W.2d 257 (Tenn.1997), (declined to expressly adopt, but allowed trial court to consider, Daubert). Courts in Ohio and Maine have used Daubert. Miller v. Bike Athletic Co., 80 Ohio St.3d 607, 687 N.E.2d 735, 741 - 742 (1998); State v. MacDonald, 718 A.2d 195, 198-199 (Me.1998). Colorado has cited to Daubert for the proposition that in application of Colorado's statute the evidence must be both reliable and relevant, and that a trial court may consider the factors listed in Daubert. People v. Shreck, 22 P.3d 68, 77 (Colo.2001).
Courts in seven states apply the Frye or a modified Frye test. Rickgauer v. Sarkar, 804 So. 2d 502, 504 (Fla.App.2001), (Florida courts still apply the Frye test in determining the admissibility of scientific evidence, as the Florida Supreme Court has declined to apply Daubert); Goeb v. Tharaldson, 615 N.W.2d 800, 814 (Minn.2000), (modified Frye standard used and Daubert rejected); Kansas City Southern Ry. Co., Inc. v. Johnson, 798 So. 2d 374, 382 (Miss.2001), (uses Frye test and has not adopted Daubert); State v. Free, 351 N.J.Super. 203, 798 A.2d 83, 93 (App.Div.2002), (state jurisprudence is consistent with Frye and not Daubert); People v. Johnston, 273 A.D.2d 514, 709 N.Y.S.2d 230, 236 , lv. denied, 95 N.Y.2d 935, 721 N.Y.S.2d 612, 744 N.E.2d 148 (Frye applied); State v. Copeland, 130 Wash. 2d 244, 922 P.2d 1304, 1314-315 (1996), (Frye test applied and declined to adopt Daubert); Armstrong v. City of Wichita, 21 Kan.App.2d 750, 907 P.2d 923, 929 (1996), (Daubert not applied and Frye applied). An additional two state courts have declined to adopt Daubert. Carnell v. Barker Management, Inc., 137 Idaho 322, 48 P.3d 651, 656-657; Krause Inc. v. Little, 34 P.3d 566, 569 (Nev. 2001).
Pennsylvania continues to apply the Frye test, Commonwealth, Dept. of General Services v. United States Mineral Products Co., 809 A.2d 1000, 1021 n. 5 (Pa.Cmwlth. 2002), but it has not yet considered whether it should be replaced by Daubert. Commonwealth v. Davies, 811 A.2d 600, 604 n.2 (Pa.Super 2002), citing, Commonwealth v. Crews, 536 Pa. 508, 640 A.2d 395, 400 n. 2 (1994).
Courts in Illinois, Missouri, and North Dakota have not yet considered the issue. Donaldson v. Central Illinois Public Service Co., 199 Ill. 2d 63, 767 N.E.2d 314, n.1, 325, (2002); Long v. Missouri Delta Medical Center, 33 S.W.3d 629, 643 (Mo. App. 2001); Hamilton v. Oppen, 2002 N.D. 185, ¶ 20, n.2, 653 N.W.2d 678, 685.
Utah uses a test similar to Daubert. State v. Crosby, 927 P.2d 638, 641-642 (Utah 1996). South Carolina applies neither a Frye or Daubert test. State v. Council, 335 S.C. 1, 515 S.E.2d 508, 517 - 518 (1999), cert. denied, 528 U.S. 1050, 120 S. Ct. 588, 145 L. Ed. 2d 489 (1999). Georgia has not adopted the federal rule and Daubert has thus not been adopted. Norfolk Southern Railway Co. v. Baker, 237 Ga.App. 292, 514 S.E.2d 448, 451 (1999).
Arizona declined to adopt the Daubert test in Logerquist v. McVey, 196 Ariz. 470, 1 P.3d 113 (Ariz. 2000). An Arizona appellate court has opined that Logerquist endorsed California's distinction between medical evidence and scientific evidence, and that a special rule for admissibility applied to the latter and not the former. State ex rel. Romley v. Fields, 201 Ariz. 321, 35 P.3d 82, 88 (Ariz.App.2001). California uses the Kelly test for admitting novel scientific evidence. People v. Soto, (1999) 21 Cal. 4th 512, 88 Cal. Rptr. 2d 34, 981 P.2d 958, n. 2, 960, 962, citing, People v. Kelly, (1976) 17 Cal. 3d 24, 30, 130 Cal. Rptr. 144, 549 P.2d 1240.
3 The relief selected upon recasting must be procedurally proper. City of Lawton v. International Union of Police Associations, Local 24, 2002 OK 1, ¶ 15, 41 P.3d 371, 377, (on post-appeal certiorari review of a decision by the Court of Civil Appeals an appeal could not be recast to a review of a certified interlocutory order). This court has recast a petition for certiorari to review a certified interlocutory order to a petition for writ of prohibition. Cleghorn v. Maples, 1994 OK 7, 867 P.2d 1272. This Court has reviewed trial court orders in the context of extraordinary relief when necessary to clarify district court procedure. See note 4 infra.

4 When deciding to recast a proceeding we have considered whether the issue before us is one of first impression. S.W. v. Duncan, 2001 OK 39, ¶ 13, 24 P.3d 846. The concept of judicial economy is present in those procedures designed to prevent an appellate court from hearing the same matter more than once. Patel v. OMH Medical Center, Inc., 1999 OK 33, ¶ 22, 987 P.2d 1185, 1195. Judicial economy does not serve as a sole reason for this Court to assume original jurisdiction. Keating v. Johnson, 1996 OK 61, n.7, 918 P.2d 51, 57; Council on Judicial Complaints v. Maley, 1980 OK 32, 607 P.2d 1180, 1182, (judicial economy interests for assuming jurisdiction were not persuasive). We have assumed original jurisdiction to clarify a trial court procedure. Carman v. Fishel, 1966 OK 130, 418 P.2d 963, 968, overruled on other grounds, Tuller v. Shallcross, 1994 OK 133, 886 P.2d 481, 485. See also, Orthopedic Clinic v. Jennings, 1971 OK 16, 481 P.2d 139, 140, (new procedural questions were raised involving appeals and vacating judgments); Miears v. District Court of Oklahoma County, 1974 OK 18, 519 P.2d 485, (new court rule that resulted from a then recent opinion of the United States Supreme Court). Whether Daubert applies in civil proceedings is a new procedural question for Oklahoma courts statewide when applying our Evidence Code, and the question arises because of recent opinions of the U. S. Supreme Court.

5 12 O.S.2001 § 2702:
Testimony by Experts
If scientific, technical or other specialized knowledge will assist the trier of fact to understand the evidence or to determine a fact in issue, a witness qualified as an expert by knowledge, skill, experience, training or education may testify in the form of an opinion or otherwise.

6 12 O.S.Supp.2002 § 2703:
Bases of Opinion Testimony by Experts
The facts or data in the particular case upon which an expert bases an opinion or inference may be those perceived by or made known to the expert at or before the hearing. If of a type reasonably relied upon by experts in the particular field in forming opinions or inferences upon the subject, the facts or data need not be admissible in evidence in order for the opinion or inference to be admitted.

7 12 O.S.2001 § 2704:
Opinion on Ultimate Issue
Testimony in the form of an opinion or inference otherwise admissible is not objectionable because it embraces an ultimate issue to be decided by the trier of fact.

8 12 O.S.Supp.2002 § 2705:
Disclosure of Facts or Data Underlying Expert Opinion
An expert may testify in terms of opinion or inference and give reasons therefor without previous disclosure of the underlying facts or data, unless the court requires otherwise. The expert may in any event be required to disclose the underlying facts or data on cross-examination.

9 The factor "widespread acceptance of the theory or technique within the relevant scientific community" is similar to Frye. Frye imposed a "general acceptance" test. Taylor v. State, 889 P.2d 319, 324 n.13, 327-329 (Okla.Cr.1995). According to one court, Daubert in courts applying a "widespread acceptance" analysis allow admission of evidence that satisfies the more restrictive Frye test. State v. Kinney, 171 Vt. 239, 762 A.2d 833, 841 (2000).

10 For example, in Gulf Oil Corp. v. Simmons, 1946 OK 317, 174 P.2d 359, we affirmed a judgment where the trial judge sustained objections to an expert's opinion on the value of cattle when nothing showed of record that the expert's opinion was based upon the proper criteria, i.e, the "material facts of age and breed" of the cattle. Id. 174 P.2d at 361. We have also reversed a judgment when an expert's testimony on an issue was not based upon a knowledge of the proper facts needed to determine the issue. See, e.g., Kappler v. Storm, 1915 OK 895, 153 P. 1142, 1143, (one reason for reversal was that the expert claimed experience from observation, but the extent of that observation was not shown, and he revealed no knowledge of those facts considered by courts when determining the particular issue before the court).

11 See also State v. Moeller, 616 N.W.2d 424, 449, 2000 SD 122, 86 -87, (Daubert hearing for expert's testimony was not needed because the challenged evidence did not present any new scientific theory, the methodologies were neither complex nor unusual, analysis was made by well-established method in the field, and there was no evidence in the record that expert's methodology or analysis was so skewed as to alter the otherwise reliable scientific method); Seivewright v. State, 7 P.3d 24, 30 (Wyo.2000), (because of the wide acceptance of bite mark identification testimony and defendant's failure to present evidence challenging the methodology, the trial court's failure to hold a Daubert hearing to analyze the expert's testimony was not an abuse of discretion). Cf. U.S. v. Havvard, 117 F. Supp. 2d 848 (S.D. Ind. 2000), (latent fingerprint identification satisfied the standards of reliability for admissible expert testimony).

12 See McKye v. State Election Bd. of State of Oklahoma, 1995 OK 15, 890 P.2d 954, 956, (extraordinary proceeding is independent action); Schofield v. Melton, 1933 OK 447, 25 P.2d 279, 282, (claims must be presented to the trial court before seeking prohibition); S.W. v. Duncan, 2001 OK 39, n. 14, 24 P.3d 846, 855, (the record in an original jurisdiction proceeding is usually in the form of an appendix supplied by each party).

13 Matchen v. McGahey, 1969 OK 48, 455 P.2d 52, 57. See Ruland v. Zenith Const. Co., 1955 OK 132, 283 P.2d 540, 541, (the cause of a medical illness is a matter of medical science to be established by expert testimony); Boxberger v. Martin, 1976 OK 78, 552 P.2d 370, 373 - 374, (noting general rule and explaining exception that expert medical testimony is not required to establish the cause of an objective injury where there is competent evidence, without such testimony, to establish the cause with reasonable certainty).

14 Amorgianos v. National R.R. Passenger Corp., 303 F.3d 256, 268 (2d Cir. 2002); Neal v. Dow Agrosciences LLC, 74 S.W.3d 468, 472 (Tex.App.Dallas, 2002); Fulmore v. CSX Transp., Inc., 252 Ga.App. 884, 557 S.E.2d 64, 72 (2001), (stating definitions of general and specific causation).

15 For example, an action to decide whether vibrations of factory machinery caused injury in a specific adjacent house involves the issue of whether the machinery has a tendency (probability) or capacity (possibility) to produce such an effect generally. J. Wigmore, The Science of Judicial Proof, § 135 (3d ed. 1937). The tendency or capacity of a thing to produce, or cause, an effect of a given sort "is to be evidenced by instances of the same effect found attending the same thing elsewhere, these other instances have probative value to show such a tendency or capacity only so far as the conditions or circumstances in the other instances are similar to the case at hand." J. Wigmore, The Science of Judicial Proof, § 136 (3d ed. 1937), emphasis in original. "The similarity that is required is, in short, a similarity in essential circumstances, or, as it is usually expressed, a substantial similarity, i.e., a similarity in such circumstances or conditions as might supposedly affect the result in question." Id.

16 For example, The Federal Judicial Center, Reference Manual on Scientific Evidence, 422 - 423 (2d ed.2000), discusses showing causation by in vitro experiments, "theories of bioplausibility", deductive clinical reasoning "based on known facts about the toxic effects of a chemical", regulatory standards, etc. We decline to address the application of any of these theories in advance of the parties framing the issues.

17The term "epidemiology" has been defined as follows:
"Epidemiology is the field of public health and medicine that studies the incidence, distribution, and etiology of disease in human populations. The purpose of epidemiology is to better understand disease causation and to prevent disease in groups of individuals. Epidemiology assumes that disease is not distributed randomly in a group of individuals and that identifiable subgroups, including those exposed to certain agents, are at an increased risk of contracting particular diseases." Federal Judicial Center, Reference Manual on Scientific Evidence, 335 (2d ed.2000).
"Epidemiology is concerned with the incidence of disease in populations and does not address the question of cause of an individual's disease. This question, sometimes referred to as specific causation, is beyond the domain of the science of epidemiology. Epidemiology has its limits at the point where an inference is made that the relationship between an agent and a disease is causal (general causation) and where magnitude of excess risk attributed to the agent has been determined; that is, epidemiology addresses whether an agent can cause a disease, not whether an agent did cause a specific plaintiff's disease." Federal Judicial Center, Reference Manual on Scientific Evidence, 381-382 (2d ed.2000).

18 Hollander, 289 F.3d at 1209-1210, comparing, Westberry v. Gislaved Gummi AB, 178 F.3d 257, 262-66 (4th Cir.1999) and Glastetter v. Novartis Pharms. Corp., 252 F.3d 986, 989 (8th Cir.2001). See also Federal Judicial Center, Reference Manual on Scientific Evidence, 34-38 (2d ed. 2000), comparing Moore v. Ashland Chemical Inc., 151 F.3d 269 (5th Cir. 1998), cert. denied, 526 U.S. 1064, 119 S. Ct. 1454, 143 L. Ed. 2d 541 (1999), and Heller v. Shaw Industries, Inc., 167 F.3d 146 (3rd Cir. 1999).

19 ipse dixit - "He himself said it; a bare assertion resting on the authority of an individual." Black's Law Dictionary, 961 (4th ed. 1951).

20 It has been said that "it is common that medical experts often disagree on diagnosis and causation, questions of conflicting evidence must be left for the jury's determination." Hose v. Chicago Northwestern Transp. Co., 70 F.3d 968, *976 (8th Cir. 1995). We recognize that experts may disagree on the issue of causation when they use either similar or dissimilar methods for arriving at their conclusions in a particular case.

21 In the context of summary judgment we have explained that a judicial determination that no material evidence exists in the trial court record to support a claim or defense is a determination of an issue of law that is reviewed de novo. Barker v. State Ins. Fund, 2001 OK 94, ¶7, 40 P.3d 463, 466. In Barker we also explained that a determination based upon no disputed facts is reviewed using a de novo standard). Id. at ¶ 7, 40 P.3d at 467. This principle is consistent with Lefthand v. City of Okmulgee, 1998 OK 97, ¶ 7, 968 P.2d 1224, 1226, where we said that a question of fact involving proximate cause becomes question of law when either the facts are undisputed or there is no evidence to support the causation element of the action.

22 A motion in limine is a motion preliminary to trial, and advisory until finally determined at trial, to preclude the introduction of prejudicial matters to the jury. Myers v. Missouri Pacific R. Co., 2002 OK 60, n. 66, 52 P.3d 1014, 1033, quoting, Middlebrook v. Imler, Tenny & Kugler, M.D.'s, Inc., 1985 OK 66, ¶ 12, 713 P.2d 572, 579. The motion has been recognized by Oklahoma case law. Messler v. Simmons Gun Specialties, Inc., 1984 OK 35, 687 P.2d 121, 127.