COMMONWEALTH OF MASSACHUSETTS

TABLE OF CONTENTS

Table of Authorities.................................. ii

Interest of Amici...................................... 1

Question Presented..................................... 2

Statement of the Case.................................. 3

Statement of Facts..................................... 4

Summary of Argument.................................... 5

ARGUMENT............................................... 8

THE PROFFERED TESTIMONY OF APPELLEE'S EXPERT

DOES NOT MEET THE STANDARDS FOR ADMISSIBILITY

ARTICULATED IN LANIGAN OR DAUBERT...................... 8

I. The establishment of causation requires a

well defined theory, or hypothesis

which is "falsifiable."......................... 11

II. Multiple Chemical Sensitivity (MCS) has no

well-defined and accepted set of symptoms....... 22

III. Multiple Chemical Sensitivity has no

well-defined and accepted cause or

surrogate cause................................. 26

IV. There is no statistical association between

any set of symptoms and the postulated cause

or surrogate cause.............................. 26

V. Without a statistical association between

a postulated cause and effect there is not

even a first step in the logical assignment

of general causation............................ 29

CONCLUSION............................................ 31

Biographical Appendix................................ A-1

TABLE OF AUTHORITIES

MASSACHUSETTS CASES

Canavan's Case,

48 Mass. App. Ct. 297 (1999).................... passim

Commonwealth v. Lanigan, 419 Mass. 15 (1994)...... passim

Commonwealth v. Vitello, 376 Mass. 426 (1978).... 21, n.6

Hachadourian's Case, 340 Mass. 81 (1959).............. 13

Linnen v. A.H. Robins Company,

11 Mass. L. Reptr. No. 2, 40,

2000 WL 116769 (Mass. Super. 2000)............. 21, n.6

Rodrigues’s Case, 296 Mass. 192 (1936)................ 13

Vassallo v. Baxter Healthcare Corp.,

428 Mass. 1 (1998)............................. 10, n.3

FEDERAL CASES

Daubert v. Merrell Dow Pharmaceuticals, Inc.,

509 U.S. 579 (1993), on remand, 43 F.3d 1311

(9th Cir. 1995), cert. denied, 516 U.S. 869,

(1995).......................................... passim

Frye v. United States, 293 F. 1013

(D.C. Cir. 1923).................................... 15

General Electric Co. v. Joiner, 522 U.S. 136

(1997), rev’g 78 F.3d 524 (11th Cir. 1996)...... passim

Kumho Tire Co. v. Carmichael, 526 U.S. 137

(1999).......................................... passim

Moore v. Ashland Chem., Inc., 151 F.3d 269

(5th Cir. 1998), cert. denied,

119 S.Ct. 1454 (1999)............................... 11

Whiting v. Boston Edison Co., 891 F. Supp. 12

(D. Mass 1995)................................. 21, n.6

MISCELLANEOUS

American College of Physicians,

Annals of Internal Medicine, Clinical

Ecology 111:168-178 (1989).......................... 23

American Society of Occupational and Environmental

Medicine (ACOEM) Statement approved by

ACOEM directors, April 26, 1999, (http://

www.acoem.org/paprguid/papers/mcs.htm) ........ 17, 22

Council on Scientific Affairs, American

Medical Association, Statement, Journal of

the American Medical Association 268:3465 (1992). 22-23

Environmental Health Perspectives 105

(Supp. 2):205-548 (1997)........................ 24, 26

Federal Judicial Center, Reference Manual on

Scientific Evidence (1994)........................... 22, 28

Graveling, et al., Occup. Envir. Med.

56(2):73-85 (1999).................................. 25

A. B. Hill, "The Environment and Diseases:

Association and Causation," 58 Proc. Royal

Soc. Med., Sec. Occup. Med. 295 (1965).............. 29

Interagency Workshop on Multiple Chemical

Sensitivity, Report on Multiple Chemical

Sensitivity (MCS) [Predecisional Draft] (1998)... 23-24

D.L. Jewett, G. Fein and M.H. Greenberg,

A Double-Blind Study of Symptom Provocation

to Determine Food Sensitivity, New England

Journal of Medicine 323:429-434 (1990).............. 28

H. Kipen and N. Fielder, Experimental

Approaches to Chemical Sensitivity,

Environmental Health Perspectives

105(Supp. 2):405-15 (1997)...................... 24, 25

M. Lessof, Report of Multiple Chemical

Sensitivity (MCS) Workshop,

Berlin, Germany, 21-23 February 1996,

PCS/96.29 IPCS (1997)............................... 23

K. Popper, Conjectures and Refutations:

The Growth of Scientific Knowledge (5th ed. 1989)............ 16

Position Statement, Idiopathic Environmental

Intolerances, 103 J. Allergy Clin.

Immunology 36 (1999)................................ 23

H. Staudenmeyer, J.C. Selner and M.P. Buhr,

Double-Blind Provocation Chamber Challenges

in 20 Patients Presenting with "Multiple

Chemical Sensitivity," Regulatory Toxicology

and Pharmacology 18:44-53 (1993).................... 28

G. Ziem, Environmental Health Perspectives 105

(Supp. 2):431 (1997)................................ 28

INTEREST OF AMICI

Amici are scientists who have studied the role that scientific issues play in public affairs and in particular the way in which they can illuminate disputes between different persons or elements of society in the courts of law; they include medical doctors, professors of epidemiology, toxicology, other branches of medicine, professors of public health, and other health sciences, as well as professors and other scientists in the field of environmental science and other fields relevant to the scientific issues in this case.[1] Several of the amici submitted a brief cited with approval by the United States Supreme Court in Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579 (1993) (hereafter "Daubert"), the seminal case discussing the rule for admissibility of expert scientific evidence. Amici support the principles enunciated by the United States Supreme Court in Daubert and by this Court in Commonwealth v. Lanigan, 419 Mass. 15 (1994) (hereafter "Lanigan"); amici believe that those principles are sound, are based on an correct understanding of scientific inquiry, and should have wide applicability at the interface between science on the one hand and law and policy on the other.

Amici were concerned to learn that the Appeals Court in Theresa Canavan's Case, 48 Mass. App. Ct. 297 (1999), held in substance that testimony as to medical causation may be based solely on “experience” and not on logical argument, is sufficiently reliable and relevant under the standards of Lanigan and Daubert to be admissible. Amici further believe that the decision of the Administrative Law Judge, affirmed by the Appeals Court, to accept that part of the testimony of appellee's expert, Dr. LaCava, that dealt with medical causality was well outside the scope of the guidelines enunciated by the United States Supreme Court in Daubert and further endorsed and explained by the United States Supreme Court in General Electric Co. v. Joiner, 522 U.S. 136 (1997) (hereafter "Joiner") and by this Court in Lanigan.

QUESTION PRESENTED

This appeal by Brigham and Women's Hospital (hereafter "Brigham" or "the hospital") presents several issues. This brief addresses only the question whether expert testimony about an alleged causal relationship between exposure to chemicals and an exposed individual’s “multiple chemical sensitivity” is admissible if it is based only on the expert’s personal observations, clinical experience, and his own methodology,[2] with no

rational explanation, no empirical support, no peer review, no publication of data, hypotheses or methodology, and without adherence to accepted scientific methodology.

STATEMENT OF THE CASE

This case arises from a worker's compensation claim of Appellee, who was a nurse at Brigham and Women’s Hospital in Boston and who alleges that she was exposed to low levels of a number of unspecified chemicals in the course of her work in the hospital. She complained of a number of symptoms, ranging from headaches to symptoms of arthritis, which she attributed to the chemical exposures. Canavan’s Case, 48 Mass. App. Ct. 297, 298 (1999). The hospital paid compensation for Ms. Canavan's sinusitis, but denied additional benefits when she claimed total disability because of the various other symptoms of which she complained. Dr. LaCava testified on her behalf (over the objection of the counsel for Brigham and Women’s Hospital based upon Commonwealth v. Lanigan, 419 Mass. 15 (1994) and the principles enunciated in Federal Rules of Evidence as clarified by Daubert, Joiner and Kumho Tire Company, Ltd. v. Carmichael, 526 U.S. 137 (1999) (hereafter "Kumho")) that her many problems arose from a disease called "Multiple Chemical Sensitivity (or MCS) secondary to chemical poisoning” and went on to argue that the chemical poisoning was caused by Brigham and Women’s Hospital. Canavan’s Case, 48 Mass. App. Ct. 297, 298 (1999)

After the Administrative Law Judge and the Department of Industrial Accidents Reviewing Board both ruled in favor of the claimant, Brigham and Women’s Hospital appealed to the Appeals Court which affirmed, holding that Dr. LaCava’s evidence was admissible under an analysis required in Lanigan.

The Appeals Court, while admitting that the evidence for causation was troubling, affirmed the administrative law judge's ruling admitting and considering the evidence of Dr. LaCava as to medical causation despite the fact that Dr. LaCava had failed to discuss the nature and extent of the appellee's exposure, had failed to point to a generally accepted definition of the symptoms defining the purported disease, and had failed to discuss any statistical association between the postulated cause and the symptoms. Neither Dr. LaCava, the Administrative Law Judge nor the Appeals Court described any logical chain of reasoning that could establish either general causation or specific causation.

STATEMENT OF FACTS

Amici adopt the statement of facts of Appellant, Brigham and Women's Hospital, as supplemented by specific facts cited in the argument below.

SUMMARY OF ARGUMENT

Under this Court's ruling in Commonwealth v. Lanigan, 419 Mass. at 25, "The overarching issue is 'the scientific validity -- and thus the evidentiary relevance and reliability -- of the principles that underlie a proposed submission.'" (emphasis supplied) Thus when assessing the admissibility of testimony based on the MCS theory, one must consider how scientists would determine its validity. As the Daubert Court recognized, “[s]cientific methodology today is based on generating hypotheses and testing them to see if they can be falsified; indeed, this methodology is what distinguishes science from other fields of human inquiry." Daubert v. Merrell Dow Pharmaceuticals, 509 U.S. 579, 593. Under Lanigan, Massachusetts follows the United States Supreme Court’s holding in Daubert, that an "expert’s opinion must 'have a reliable basis in the knowledge and experience of his discipline.'" 419 Mass. at 25 (quoting Daubert, 509 U.S. at 592). The court must make "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." 419 Mass. at 26 (quoting Daubert, 509 U.S. at 592-93). (pp. 8-11.)

Ms. Canavan's claim is grounded in the testimony of only one expert witness -- Dr. LaCava. That testimony was deemed admissible by the Appeals Court even though it was based only on the expert’s personal observations, clinical experience, and his own methodology, with no rational explanation, no empirical support, no peer review, no publication of data, hypotheses or methodology, and without adherence to accepted scientific methodology; he has no recognized credentials in the field about which he testified. The decision of the Appeals Court would allow an expert to circumvent the Lanigan/Daubert requirements for scientifically valid reasoning merely by claiming reliance on training, experience, and clinical observations. If allowed to stand, it would render Lanigan/Daubert virtually meaningless. Indeed, the United States Supreme Court in Kumho specifically rejected such an approach, and we submit this Court should do likewise. We further submit that, contrary to the reasoning of the Appeals Court, there is no controlling Massachusetts precedent that requires a different approach. (pp. 11-22.)

The opinion of the Appeals Court is based on a flawed perception of what constitutes proof of causation in medicine. Daubert itself, and Joiner, which followed it, apply the "Daubert factors" to medical science and specifically the issue of causation of disease. These factors correctly describe the criteria for establishing scientifically credible explanations -- theories or hypotheses -- for observed phenomena. (pp. 11-15.)

Issues of causation of disease are resolved in medicine using the methodology outlined in Daubert and Lanigan: formulating an hypothesis, testing the hypothesis, subjecting the hypothesis and the test data to review and testing by others (primarily through publication and peer review), and, if appropriate, refinement, revision or discarding of the hypothesis. The process is not finished when one has accumulated data, however reliable, until the hypothesis has been properly stated and tested. (pp. 17-22.)

There are even more fundamental difficulties with the testimony of appellee's sole expert in this case. The diagnosis, "multiple chemical sensitivity," is not generally recognized within the medical community, and it has no defining criteria. The exposure implied by the name of the "disease" is so vague as to be meaningless and not measurable. Without an objectively verifiable disease and without specific exposure criteria, it is impossible to determine or even consider causation. This is a case of a label -- "multiple chemical sensitivity" -- suggesting both a disease and a cause, when there is no evidence for either. (pp. 22-26.)

The testimony at issue here and the process by which appellee's expert on causation reached his conclusion do not satisfy the Daubert/Joiner/Kumho criteria or the Lanigan criteria for reliability, and the Administrative Law Judge and the Industrial Accident Reviewing Board should have precluded Dr. LaCava from testifying as an expert and clearly should have excluded his testimony on causation. (pp. 28-32.)

Amici submit that the Appeals Court did not apply the appropriate legal criteria, or applied them incorrectly, in reviewing the Board's decision.

ARGUMENT

THE PROFFERED TESTIMONY OF

APPELLEE'S EXPERT DOES NOT MEET

THE STANDARDS FOR ADMISSIBILITY

ARTICULATED IN LANIGAN OR DAUBERT

As this Court said in Commonwealth v. Lanigan, 419 Mass. at 25, "The overarching issue is 'the scientific validity -- and thus the evidentiary relevance and reliability -- of the principles that underlie a proposed submission.'" (emphasis supplied) Thus when assessing the admissibility of testimony based on the MCS theory, one must consider how scientists would determine its validity. Likewise, the United States Supreme Court in Daubert recognized that “[s]cientific methodology today is based on generating hypotheses and testing them to see if they can be falsified; indeed, this methodology is what distinguishes science from other fields of human inquiry." Daubert v. Merrell Dow Pharmaceuticals, 509 U.S. 579, 593. Under Lanigan, Massachusetts follows the United States Supreme Court’s holding in Daubert, that an "expert’s opinion must 'have a reliable basis in the knowledge and experience of his discipline.'" 419 Mass. at 25 (quoting Daubert, 509 U.S. at 592). The court must make "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." 419 Mass. at 26 (quoting Daubert, 509 U.S. at 592-93).

Ms. Canavan's claim is grounded in the testimony of only one expert witness -- Dr. LaCava. That testimony was based only on the expert’s personal observations, clinical experience, and his own methodology, with no rational explanation, no empirical support, no peer review, no publication of Dr. LaCava's data, hypotheses or methodology, and without adherence to accepted scientific methodology; further, Dr. LaCava has no recognized credentials in the field about which he testified.

The decision of the Appeals Court would allow an expert to circumvent the Lanigan/Daubert requirements for scientifically valid reasoning merely by claiming reliance on training, experience, and clinical observations. If allowed to stand, it would render Lanigan/Daubert virtually meaningless. Indeed, the United States Supreme Court in Kumho specifically rejected such an approach, and we submit this Court should do likewise. We further submit that, contrary to the reasoning of the Appeals Court, there is no controlling Massachusetts precedent that requires a different approach.

I. The establishment of causation requires a

well defined theory, or hypothesis

which is "falsifiable."

As one of the amici, Professor Alvan R. Feinstein wrote in an amicus brief filed in another case, "determining the etiology of a disease -- its cause --involves the same scientific exercise, whether the decision is made by a clinician, an epidemiologist, or other scientist." See Moore v. Ashland Chem., Inc., 151 F.3d 269, 275 n. 6 (5th Cir. 1998), cert. denied, 119 S.Ct. 1454 (1999). The clinical practice of medicine involves the application of scientific knowledge, and testimony regarding clinical medicine is subject to the same evidentiary standards as any other testimony relating to science or the application of scientific principles or data. This conclusion was clearly the basis of three United States Supreme Court opinions: In Daubert the Supreme Court emphasized that a trial judge "must ensure that any and all scientific testimony or evidence admitted is not only relevant, but reliable" (509 U.S. at 589), going on to state that "reliability" in this context means not only consistency of results but also what scientists term "validity" or correspondence to reality (509 U.S. at 590, n. 9). In Joiner, the Court emphasized the importance of reliability and that in assessing reliability there are a number of factors to be considered. In Kumho the Court broadened the applicability of the Daubert criteria, and held that those criteria have general validity, and apply as much to cases where there is more "art" or experience as they do to quantitative science in cases where causation can be expressed quantitatively. One factor stated in Daubert is whether the work has been subjected to peer

review or otherwise been open to discussion and criticism outside the strict bounds of this case.

The Appeals Court itself conceded that "the more troubling issue in this case is the admissibility of Dr. LaCava’s opinion on causation." Canavan, 428 Mass. App. Ct. at 301. Dr. LaCava "admitted that the cause of the disease is in dispute." Id. In the next paragraph the Appeals Court argued that the question of medical causation is "beyond the . . . knowledge of the ordinary layman . . . and proof of it must rest upon expert testimony." Id. at 302, citing Hachadourian's Case, 340 Mass. 81, 85 (1959). In the opinion of amici the appeals court erred in accepting Dr. LaCava’s opinion on causation. The court stated that "the employee’s medical expert was well aware and informed about the nature of the chemicals to which the employee had been exposed," Canavan at 302, yet Dr. LaCava denied any such specific knowledge, relying instead on his own experience at other hospitals and undisclosed histories of other patients who had worked in the same "pod" at Brigham. LaCava Dep. at 13-14, 62, 85, R.A. 386-87, 435, 458.[4] Moreover knowledge of possible exposures, when there also exist a vast number of other exposures to chemicals in everyday life, is inadequate to qualify as evidence for causation. Amici do not believe that such would be a "reasonable inference" in the sense of Rodrigues’s Case, 296 Mass. 192, 195 (1936). The Appeals Court also stated that "the judge could properly take into account that Dr. LaCava’s opinion was buttressed by his knowledge that other patients. . .were similarly afflicted . . . . " Id. at 302. Even if this could loosely be called a "study," they constitute merely case reports, and are data sets that lack comparison groups, and thus are not the type of information upon which experts in medical causation would rely in forming an opinion as to the cause of an observed condition.[5] Dr. LaCava's testimony is just this kind of proffered testimony that the United States Supreme Court excluded in Joiner. The Appeals Court failed to observe the similarity between the type of expert evidence offered in this case and those cases, and rejected by the United States Supreme Court. Indeed, the scientific basis for Dr. LaCava's testimony is even weaker than that involved in Daubert and Joiner.

Both Daubert and Joiner were cases involving medical science and the causation of the plaintiff’s condition. In both cases the issue on appeal was the exclusion by the trial court of proffered testimony as to causation. In Daubert the issue was whether the deformities of plaintiffs’ child were caused by the alleged mutagenic effects on fetuses of the drug Bendectin taken by mothers during pregnancy. In Joiner the issue was whether the plaintiff's exposure to fumes from polychlorinated biphenyls (PCBs) caused or contributed to his small cell lung carcinoma. In both Daubert and Joiner, the proffered evidence that was excluded was testimony as to claimed evidence of causation. The plaintiffs in Daubert claimed that various problems that appeared in pregnancy and childbirth were due to use of the drug Bendectin. The Supreme Court, declining to adopt the "Frye rule," (originating in Frye v. United States, 293 F. 1013 (D.C. Cir. 1923)) set forth a number of criteria for determining the scientific validity of proffered testimony:

1. Has the theory been tested or can it be tested? In other words, is it falsifiable?

2. Has the theory been peer reviewed and published?

3. What is the known or potential risk of error?

4. Has the theory been generally accepted in the relevant scientific community?

5. Is the theory based on facts or data of a type reasonably relied upon by experts in the field?

6. Does the testimony have probative value that is greater than, or not outweighed by, a danger of unfair prejudice, confusion of issues, or misleading the jury?

Daubert, 509 U.S. at 593-594.

In all of these questions, the Supreme Court assumed that there is a well defined theory, postulate or question that can be tested: Does cause (or surrogate cause) "A" lead to an effect (or increased probability of an effect) "B."

In the Canavan case the situation is far worse. There is no well-defined disease, no well-defined postulated cause and no well-defined theory: what are the characteristics of the disease being discussed, what is the postulated cause or contributory cause, and is there an association between the two which satisfies all the proper statistical tests? Not until these questions are answered can one then begin to address the issue of causation. In simpler words, it is not possible to properly discuss medical causation until there is a well-defined theory to test or question to answer. As Sir Karl Popper put it, a scientific theory must be falsifiable. See K. Popper, Conjectures and Refutations: The Growth of Scientific Knowledge 37 (5th ed. 1989) ("[T]he criterion of the scientific status of a theory is its falsifiability, or refutability, or testability" (emphasis deleted); see Daubert at 593. In the opinion of amici these predicates do not exist in this case.

In his deposition testimony, Dr. LaCava defined Multiple Chemical Sensitivity (MCS) as a "systemic reaction of the body" (LaCava Dep. at 23, R.A. 396), "with multiple organ system complaints by individuals to low levels of multiple chemical substances, often including psycho-neurological symptoms" (LaCava Dep. at 76, R.A. 449) "which may be chemically unrelated, which are commonly present in the everyday working and living environment where that environment has not been meticulously cleaned up and had the chemical sources removed." (LaCava Dep. at 23-24, R.A. 396-97) This general, and somewhat vague, definition falls far short of the specificity necessary. The use of the phrase "chemical sensitivity" in the definition assumes some degree of causation before there is proof of causation; it is an example of circular reasoning. Amici maintain there is no proof of causation. Many authorities prefer to call this alleged disease “Idiopathic Environmental Intolerance” (i.e., an intolerance with no defined cause) (See, e.g., Statement of The American Society of Occupational and Environmental Medicine (ACOEM) approved by ACOEM directors on April 26, 1999 and available on the world wide web at http://www.acoem.org/paprguid/ papers/mcs.htm(annexed as Exhibit A to the Brief of Amicus Curiae The Massachusetts Defense Lawyers Association)).

In this case the Appeals Court apparently thought testing had occurred because LaCava performed diagnostic tests on the claimant. Canavan, 48 Mass. App. Ct. at 300. Precisely what the tests might have diagnosed is not clear, given the lack of proof that MCS exists as a defined or definable disease. Such diagnostic tests, however, do not constitute testing of the hypothesis that MCS is a definable disease, and they certainly cannot substantiate the theory underlying a diagnosis of MCS as scientifically valid.

Dr. LaCava failed properly to define the symptoms (as opposed to the postulated causes) of the postulated disease (Multiple Chemical Sensitivity) nor did he, or any other witness, identify which chemicals or set of chemicals were the postulated cause. Because we are all exposed to chemicals all through our lives, primarily the chemicals in the food we eat, this is an important failure. Further, Dr. LaCava was unable to point to any study which found a statistical association between the symptoms and the postulated cause. The court must not be confused by the use of the word "chemical" in the description of the supposed disease and be led to assume that a "chemical" is a proven, or even a likely, cause of any of the symptoms. Nor must the court be confused and believe that "chemicals" are only found in the hospital environment, rather than in the food we eat, the air we breathe, the water we drink, the clothes we wear, or objects we touch throughout the day.

When Daubert was remanded to the Court of Appeals for the Ninth Circuit (because that court had applied the "Frye rule" in the proceedings that led up to the Supreme Court’s decision), that court, applying the Supreme Court’s standards, concluded that evidence to the effect that Bendectin "causes" the alleged medical problems was correctly excluded under the Daubert guidelines. Daubert v. Merrell Dow Pharmaceuticals, 43 F.3d 1311 (9th Cir. 1995), cert. denied 516 U.S. 869 (1995).

In Joiner, the issue was whether the claimed exposure to PCBs was a cause of an admitted, and well-recognized, disease. Joiner also was a case which, like this case, is about causation. In Joiner proffered expert testimony by two physicians was excluded by the trial court. The Supreme Court, reversing the Appeals Court for the Eleventh Circuit, agreed that the trial court correctly excluded the proffered evidence because it was not "reliable." In both Daubert and Joiner, the experts for the plaintiffs had not shown that their research or their review of the literature was applicable to the issue of causation in humans of the disease contracted by the plaintiff.

Indeed, in Joiner the unanimous court went further than did the majority in Daubert, and actually examined not only the methods, but also the conclusions, of the proposed experts. In Joiner respondent argued that under Daubert the "focus, of course, must be solely on principles and methodology, not on the conclusions that they generate." 509 U.S. at 595, and that because the District Court's disagreement was with the conclusion that plaintiff’s experts drew from the studies, the District Court committed legal error and was properly reversed by the Appeals Court. The Supreme Court held, however, that

[C]onclusions 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 which 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.

Joiner, 522 U.S. at 146 (1997) (citations omitted). Amici submit that this paragraph applies directly to the considerably larger analytical gap between the data relied on by Dr. LaCava and the opinion he offered.

In Kumho the Supreme Court went still further, and held that the criteria for reliability of expert testimony apply to situations in which the expert relies on training and experience rather than a claimed scientific method. Amici maintain this reasoning applies a fortiori to clinicians, and that the "treating physician" exception employed by the Appeals Court in Canavan is not proper when the clinician purports to offer opinion as to causation. We respectfully submit that the Appeals Court erred in considering that Dr. LaCava's testimony had any value. Even the most erudite of laymen, whether jurists or jurors, if they are non-scientists, tend to be confused by untested hypotheses, and that is a reason why untested hypotheses (as opposed to novel, but tested, hypotheses) are excluded by the Daubert criteria.[6]

Dr. LaCava's conclusion as to causation was not even, by his own admission, a hypothesis that could be tested. Dr. LaCava’s hypothesis has not in fact been tested, and the underlying data and the hypothesis have not been submitted for peer review.[7] In short, there has been no opportunity to "falsify" Dr. LaCava's hypothesis. Dr. LaCava's conclusion that chemicals generally, let alone chemicals in her workplace, caused plaintiff’s symptoms did not comport with the requirements of science properly conducted and correctly understood, because his test results and analytic methods have not been shared with the rest of the relevant scientific community.