Case Title: Jill Marsh v. Robert Earl Valyou, Jr., Et Al.

Citation: 

Docket Number: SC06-118

State: florida

Court: Florida Supreme Court

Date: 2007-11-21T00:00:00Z

Document:
____________ 
 
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Supreme Court of Florida  
No. SC06-118 
JILL MARSH, 
Petitioner, 
vs. 
ROBERT EARL VALYOU, JR., et al., 
Respondents. 
[November 21, 2007] 
PER CURIAM. 
In this case, we decide whether Frye v. United States, 293 F. 1013 (D.C. Cir. 
1923), applies to expert testimony causally linking trauma to fibromyalgia.  We 
review Marsh v. Valyou, 917 So. 2d 313 (Fla. 5th DCA 2005), which certified 
conflict with State Farm Mutual Automobile Insurance Co. v. Johnson, 880 So. 2d 
721 (Fla. 2d DCA 2004). In Marsh, the Fifth District Court of Appeal held that 
Frye does apply and, applying that test, held the testimony inadmissible.  See 
Marsh, 917 So. 2d at 327, 329. The Second District Court of Appeal, on the other 
hand, concluded that Frye did not apply. Johnson, 880 So. 2d at 723. We have 
jurisdiction to resolve the certified conflict, see art. V, § 3(b)(4), Fla. Const., and 
 
 
 
 
 
granted review. See Marsh v. Valyou, 940 So. 2d 1125 (Fla. 2006) (granting 
review). We conclude that Frye does not apply to expert testimony causally 
linking trauma to fibromyalgia and that, even if it did, such testimony satisfies it.  
Therefore, we quash Marsh and approve the conflicting opinion in Johnson. 
I. FACTS AND PROCEDURAL HISTORY 
After sustaining injuries in four separate car accidents between August 1995 
and January 1998, the petitioner, Jill Marsh, filed a negligence action against a 
series of four defendants—the Valyous; the Burkes; PVC Holding Corp., d/b/a/ 
Avis Rent-a-Car (“Avis”); and Scott David Chilcut (no longer a party).  Marsh, 
917 So. 2d at 315. She claimed the accidents caused fibromyalgia, which is a 
“syndrome of widespread pain, a decreased pain threshold, and characteristic 
symptoms including non-restorative sleep, fatigue, stiffness, mood disturbance, 
irritable bowel syndrome, headache, paresthesias, and other less common 
features.” Id. (quoting Frederick Wolfe, et al., The Fibromyalgia Syndrome:  A 
Consensus Report on Fibromyalgia and Disability, 23 J. Rheumatology 534, 534 
(1996) [hereinafter Consensus Report]). 
Avis moved to preclude Marsh from presenting expert testimony that the 
accidents caused her fibromyalgia, arguing that the testimony did not meet the Frye 
standard for admissibility because the premise that trauma can cause fibromyalgia 
had not been generally accepted in the scientific community.  Id.  The trial court 
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held a Frye hearing and, after reviewing numerous documents related to 
fibromyalgia and hearing arguments of counsel, granted the motion.  Id. at 315-17. 
It later became apparent that Marsh intended to introduce evidence that the 
accidents caused “myofascial pain syndrome” (MPS). Id. at 318.  Again, Avis 
challenged the testimony under Frye and the trial court precluded evidence of a 
causal link between trauma and MPS.  Id.  Marsh then announced she had no 
claims apart from fibromyalgia and MPS, and the trial court entered summary 
judgment.  Id. at 319. 
Petitioner appealed, arguing: (1) the evidence is “pure opinion testimony” 
not subject to Frye; and (2) only the basis for an expert’s opinions is subject to 
Frye, not the opinions and deductions drawn from those principles.  Id.  The Fifth 
District rejected these arguments and affirmed.  Id. at 329. The district court 
likewise affirmed the order related to MPS.1  During the pendency of the appeal, 
the Second District decided Johnson, holding that testimony that trauma from an 
automobile accident caused fibromyalgia is admissible as “‘pure opinion 
testimony’ based solely on the expert’s personal experience and training.” 880 
1. Marsh apparently has abandoned the MPS issue, as it was not addressed 
at oral argument and was largely ignored in her briefs.  Because the issue is beyond 
the scope of the certified conflict, we decline to address it.  See Borden v. East-
European Ins. Co., 921 So. 2d 587, 596 n.8 (Fla. 2006) (recognizing an issue as 
beyond the scope of the certified conflict); Kelly v. Cmty. Hosp. of the Palm 
Beaches, Inc., 818 So. 2d 469, 470 n.1 (Fla. 2002) (declining to address issues 
beyond the basis for the Court’s conflict jurisdiction).  
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So. 2d at 723 (quoting U.S. Sugar Corp. v. Henson, 787 So. 2d 3, 14 n.10 (Fla. 1st 
DCA 2000), approved, 823 So. 2d 104 (Fla. 2002)).  The Fifth District disagreed, 
concluding that testimony that trauma caused the plaintiff’s fibromyalgia requires 
“an underlying scientific assumption—that trauma can cause fibromyalgia—which 
is not involved in pure opinion testimony cases,” and certified conflict with 
Johnson. Marsh, 917 So. 2d at 327, 329. 
II. ANALYSIS 
For purposes of our review, the parties do not dispute Marsh’s diagnosis of 
fibromyalgia, or that fibromyalgia is a legitimate condition.  Instead, the issue is 
whether expert testimony causally linking trauma (the car accidents) to the onset of 
fibromyalgia is subject to the Frye test. Below we first explain why the testimony 
is not subject to Frye; and then explain that, even if the testimony had to satisfy 
Frye, it does. 
A. Frye Does Not Apply 
Many years ago, the United States Court of Appeals for the District of 
Columbia Circuit established a test for admitting expert testimony that espoused 
new or novel theories. In Frye, 293 F. at 1013, the court considered the 
admissibility of expert testimony as to the result of a “systolic blood pressure 
deception test,” an early polygraph.  The D.C. Circuit held: 
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Just when a scientific principle or discovery crosses the line between 
the experimental and demonstrable stages is difficult to define.  
Somewhere in this twilight zone the evidential force of the principle 
must be recognized, and while courts will go a long way in admitting 
expert testimony deduced from a well-recognized scientific principle 
or discovery, the thing from which the deduction is made must be 
sufficiently established to have gained general acceptance in the field 
in which it belongs. 
We think the systolic blood pressure deception test has not yet 
gained such standing and scientific recognition among physiological 
and psychological authorities as would justify the courts in admitting 
expert testimony deduced from the discovery, development, and 
experiments thus far made. 
Id. at 1014. 
Many state courts, as well as other federal courts, adopted the Frye test. 
See, e.g., 29 Charles Alan Wright & Victor James Gold, Federal Practice and 
Procedure § 6266 (1997) (recognizing that Frye was the “dominate [sic] standard 
for decades”); Alice B. Lustre, Annotation, Post-Daubert Standards for 
Admissibility of Scientific and Other Expert Evidence in State Courts, 90 A.L.R. 
5th 453, § 2 (2001) (“[Frye] was quickly adopted by most states as well as the 
other federal courts.”). We expressly adopted Frye in Bundy v. State, 471 So. 2d 
9, 18 (Fla. 1985), and Stokes v. State, 548 So. 2d 188, 195 (Fla. 1989). 
Seventy years after Frye, the United States Supreme Court held that the 
adoption of the Federal Rules of Evidence superseded the Frye test. See Daubert 
v. Merrell Dow Pharms., 509 U.S. 579, 587 (1993).  Daubert adopted a different 
test for admissibility under which the Frye test—general acceptance in the 
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scientific community—is simply one factor among several.  Id. at 594. Courts and 
commentators have since debated whether the Daubert standard is more lenient or 
more strict.  See, e.g., Allison v. McGhan Med. Corp., 184 F.3d 1300, 1312 (11th 
Cir. 1999) (“While Allison argues that the thrust of the Rules and of the Eleventh 
Circuit has been for liberal admissibility of evidence, she fails to appreciate the 
tempering qualities of Rules 403, 702 and 703 under Daubert and the fact that this 
Circuit has been twice overruled on Daubert decisions in precedent setting 
Supreme Court decisions in [General Electric Co. v.] Joiner[, 522 U.S. 136 (1997)] 
and Kumho Tire [Co. v. Carmichael, 526 U.S. 137 (1999)], both of which imposed 
stricter admissibility standards than the Eleventh Circuit had deemed 
appropriate.”); Berry v. CSX Transp., Inc., 709 So. 2d 552, 570 n.16 (Fla. 1st DCA 
1998) (“It is yet a matter of debate whether the Daubert test . . . will be more 
liberal and allow more expert testimony than the Frye requirement . . . . ”); David 
E. Bernstein & Jeffrey D. Jackson, The Daubert Trilogy in the States, 44 
Jurimetrics J. 351, 352 (2004) (“Courts and commentators disagreed, however, 
regarding whether this ‘revolution’ in how judges were to go about deciding 
whether to admit scientific evidence would lead to more permissive or more 
restrictive admissibility rulings.”) (footnote omitted); Edward K. Cheng & Albert 
H. Yoon, Does Frye or Daubert Matter? A Study of Scientific Admissibility 
Standards, 91 Va. L. Rev. 471, 471, 510 (2005) (questioning whether a state’s 
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adoption of Frye or Daubert makes any practical difference, but noting that 
“[c]ommentators have extensively debated which is the stricter standard”). Some 
commentators have suggested that, in practice, it makes no difference which test is 
used. See, e.g., Cheng & Yoon, supra, at 510. 
Despite the Supreme Court’s decision in Daubert, we have since repeatedly 
reaffirmed our adherence to the Frye standard for admissibility of evidence.  See, 
e.g., Ibar v. State, 938 So. 2d 451, 467 (Fla. 2006) (“Florida courts do not follow 
Daubert, but instead follow the test set out in Frye.”), cert. denied, 127 S.Ct. 1326 
(2007); Brim v. State, 695 So. 2d 268, 271-72 (Fla. 1997) (“Despite the federal 
adoption of a more lenient standard in [Daubert], we have maintained the higher 
standard of reliability as dictated by Frye.”); Hadden v. State, 690 So. 2d 573, 578 
(Fla. 1997) (“Our specific adoption of that test after the enactment of the evidence 
code manifests our intent to use the Frye test as the proper standard for admitting 
novel scientific evidence in Florida, even though the Frye test is not set forth in the 
evidence code.”); Flanagan v. State, 625 So. 2d 827, 829 n.2 (Fla. 1993) (“We are 
mindful that the United States Supreme Court recently construed Rule 702 of the 
Federal Rules of Evidence as superseding the Frye test. However, Florida 
continues to adhere to the Frye test for admissibility of scientific opinions.”) 
(citation omitted).  Other states have adhered to Frye as well. See, e.g., Wright & 
Gold, supra, § 6266 (noting that many states have adopted Daubert, but others have 
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declined to do so); Bernstein & Jackson, supra, at 356 (noting that Frye “remains 
the rule in a significant minority of states”); Cheng & Yoon, supra, at 473 (noting 
that a number of states have formally adopted Daubert, but many have chosen to 
retain the Frye standard). 
Under Frye, “[t]he proponent of the evidence bears the burden of 
establishing by a preponderance of the evidence the general acceptance of the 
underlying scientific principles and methodology.”  Castillo v. E.I. Du Pont De 
Nemours & Co., Inc., 854 So. 2d 1264, 1268 (Fla. 2003). We review Frye issues 
de novo, with general acceptance considered as of the time of the appeal.  Id.  “By 
definition, the Frye standard only applies when an expert attempts to render an 
opinion that is based upon new or novel scientific techniques.” U.S. Sugar Corp. 
v. Henson, 823 So. 2d 104, 109 (Fla. 2002) (emphasis added).  Therefore, we have 
recognized that Frye is inapplicable in the “vast majority” of cases.  Id.; see also 
Rickgauer v. Sarkar, 804 So. 2d 502, 504 (Fla. 5th DCA 2001) (“Most expert 
testimony is not subject to the Frye test.”). 
The expert medical causation testimony at issue here is not “new or novel.”  
The American College of Rheumatology published classification criteria for 
fibromyalgia in 1990.  Consensus Report, supra, at 534, 536 (“FM is widely 
accepted as a common generalized pain syndrome associated with characteristic 
symptoms and the finding of generalized tenderness.  The 1990 ACR Criteria for 
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the Classification of Fibromyalgia have been established and recommended for 
classification purposes in research studies.”) (footnote omitted).  Marsh’s experts 
based their diagnoses and opinions about the cause of her fibromyalgia on a review 
of her medical history, clinical physical examinations, their own experience, 
published research, and differential diagnosis.2 
Experts routinely form medical causation opinions based on their experience 
and training. See, e.g., Cordoba v. Rodriguez, 939 So. 2d 319, 322 (Fla. 4th DCA 
2006) (“Medical expert testimony concerning the causation of a medical condition 
will be considered pure opinion testimony and admissible when it is based solely 
on the expert’s training and experience.”); Gelsthorpe v. Weinstein, 897 So. 2d 
504, 510 (Fla. 2d DCA 2005) (“[M]edical expert testimony concerning the 
causation of a medical condition will be considered pure opinion testimony—and 
thus not subject to Frye analysis—when it is based solely on the expert’s training 
and experience.”); Fla. Power & Light Co. v. Tursi, 729 So. 2d 995, 996 (Fla. 4th 
DCA 1999) (finding Frye inapplicable where the physician was qualified to testify 
about the cause of a cataract based on his knowledge and experience).  And there is 
always the possibility that two experts may reach dissimilar opinions based on 
their individual experience. However, a disagreement among experts does not 
2. Differential diagnosis is “an established scientific methodology in which 
the expert eliminates possible causes of a medical condition to arrive at the 
conclusion as to the actual debilitating factor.”  U.S. Sugar, 823 So. 2d at 106. 
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transform an ordinary opinion on medical causation into a new or novel principle 
subject to Frye. See Gelsthorpe, 897 So. 2d at 511 (recognizing that “a typical 
opinion on medical causation” should not be treated as a “new principle, subject to 
Frye analysis, simply because some other experts disagree with it and because the 
challenged expert does not rely on any specific authority to support his particular 
opinion”); Tursi, 729 So. 2d at 997 (recognizing that an ophthalmologist’s opinion 
on causation was not based on “novel scientific evidence,” as “[i]t was no more 
novel than an orthopedist testifying that a neck injury, which did not manifest itself 
with symptoms until four years after a rear-end collision, was caused by the 
accident”); Berry, 709 So. 2d at 571 (recognizing that the trial will be a “battle of 
the experts” and the fact that they derived their opinions from the same studies, but 
disagree on how to interpret them, is not a valid reason for excluding their 
testimony).   
It is well-established that Frye is inapplicable to “pure opinion” testimony: 
[P]ure opinion testimony, such as an expert’s opinion that a defendant 
is incompetent, does not have to meet Frye, because this type of 
testimony is based on the expert’s personal experience and training.  
While cloaked with the credibility of the expert, this testimony is 
analyzed by the jury as it analyzes any other personal opinion or 
factual testimony by a witness. 
Flanagan, 625 So. 2d at 828; see also Hadden, 690 So. 2d at 579-80 (same); 
Herlihy v. State, 927 So. 2d 146, 148 (Fla. 1st DCA 2006) (“[A] diagnosis based 
on an expert’s opinion and experience, versus a specific scientific test, would not 
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be subject to a Frye hearing.”); Gelsthorpe, 897 So. 2d at 510-11 (finding Frye 
inapplicable to “pure opinion testimony based upon clinical experience” where the 
“testimony did not rely on any study, test, procedure, or methodology that 
constituted new or novel scientific evidence,” but instead was based on an analysis 
of medical records and differential diagnosis).  Because testimony causally linking 
trauma to fibromyalgia is based on the experts’ experience and training, it is “pure 
opinion” admissible without having to satisfy Frye. See Johnson, 880 So. 2d at 
723. 
Marsh’s experts did not base their opinions on new or novel scientific tests 
or procedures, and Respondents did not challenge the patient history, examination 
methods, clinical practices, or other methodologies upon which they did rely.  In 
fact, Respondents could not challenge the underlying methodology, as we have 
previously held that differential diagnosis is a generally accepted method for 
determining specific causation.  Castillo, 854 So. 2d at 1271; U.S. Sugar, 823 So. 
2d at 110 (“[T]here is no question that the differential diagnosis technique . . . is 
generally accepted in the scientific community.”); see also Johnson, 880 So. 2d at 
723 (recognizing that a challenge to the underlying methodology would be 
unsuccessful because differential diagnosis is a “standard scientific technique”).  
Instead, Respondents challenged the experts’ conclusions that trauma caused 
Marsh’s fibromyalgia.  However, as we stated in U.S. Sugar, 823 So. 2d at 110: 
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[U]nder Frye, the inquiry must focus only on the general acceptance 
of the scientific principles and methodologies upon which an expert 
relies in rendering his or her opinion.  Certainly the opinion of the 
testifying expert need not be generally accepted as well.  Otherwise, 
the utility of expert testimony would be entirely erased, and “opinion” 
testimony would not be opinion at all—it would simply be the 
recitation of recognized scientific principles to the fact finder. . . . We 
reaffirm our dedication to the principle that once the Frye test is 
satisfied through proof of general acceptance of the basis of an 
opinion, the expert’s opinions are to be evaluated by the finder of fact 
and are properly assessed as a matter of weight, not admissibility. 
See also Castillo, 854 So. 2d at 1276 (holding that the district court erred in 
considering “not just the underlying science, but the application of the data 
generated from that science in reaching the expert’s ultimate conclusion”); Berry, 
709 So. 2d at 567 (“[W]hen the expert’s opinion is well-founded and based upon 
generally accepted scientific principles and methodology, it is not necessary that 
the expert’s opinion be generally accepted as well.”).  
Trial courts must resist the temptation to usurp the jury’s role in evaluating 
the credibility of experts and choosing between legitimate but conflicting scientific 
views. See Castillo, 854 So. 2d at 1275 (“[I]t is important to emphasize that the 
weight to be given to stated scientific theories, and the resolution of legitimate but 
competing scientific views, are matters appropriately entrusted to the trier of fact.”) 
(quoting Berry, 709 So. 2d at 569 n.14); Rodriguez v. Feinstein, 793 So. 2d 1057, 
1060 (Fla. 3d DCA 2001) (same). A challenge to the conclusions of Marsh’s 
experts as to causation, rather than the methods used to reach those conclusions, is 
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a proper issue for the trier of fact. See U.S. Sugar, 823 So. 2d at 110; Castillo, 854 
So. 2d at 1270, 1272, 1276; Rodriguez, 793 So. 2d at 1060 (recognizing that “to 
involve judges in an evaluation of the acceptability of an expert’s opinions and 
conclusions would convert judges into fact-finders” to an extent not contemplated 
by Florida’s Frye jurisprudence). 
For these reasons, we hold that Frye does not apply to testimony of a causal 
link between trauma and fibromyalgia. 
B. The Testimony Satisfies Frye 
Even if subject to Frye, testimony linking trauma to fibromyalgia satisfies it.  
The purpose of Frye is to ensure the reliability of expert testimony.  See, e.g., 
Hadden, 690 So. 2d at 578 (“Reliability is fundamental to issues involved in the 
admissibility of evidence.”); Berry, 709 So. 2d at 568 (“At this admissibility stage 
of the proceedings, under Frye the court is asked to decide whether the basis of the 
evidence upon which plaintiffs’ experts rely has a sufficient indicia of reliability.”).  
Numerous published articles and studies recognize an association between trauma 
and fibromyalgia.3  Respondents’ own expert testified that he has seen situations 
where he thought trauma indirectly led to fibromyalgia.   
3. See, e.g., A.W. Al-Allaf et al., A Case-Control Study Examining the Role 
of Physical Trauma in the Onset of Fibromyalgia Syndrome, 41 Rheumatology 
450, 452 (2002) (concluding that the results of the study suggested “that physical 
trauma was significantly associated with the onset” of fibromyalgia); Dan Buskila 
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A lack of studies conclusively demonstrating a causal link between trauma 
and fibromyalgia and calls for further research do not preclude admission of the 
testimony.  See Castillo, 854 So. 2d at 1270 (“While epidemiology is considered 
generally accepted in the scientific community as a way of studying causal links 
between disease and chemicals, these types of studies are not necessarily required 
for a party to meet its burden of showing a causal link by a preponderance of the 
evidence.”); U.S. Sugar, 823 So. 2d at 110 (“[I]t is well settled that a lack of 
epidemiological studies does not defeat submission of expert testimony and 
opinions as expressed in this case.”); Berry, 709 So. 2d at 568 n.12 (“[T]he fact 
that an epidemiological study calls for further research does not indicate 
uncertainty on the part of the researchers.”).   
et al., Increased Rates of Fibromyalgia Following Cervical Spine Injury, 40 
Arthritis & Rheumatism 446, 451 (1997) (concluding that “trauma to the neck is 
associated with a higher incidence of FMS”); Anil Kumar Jain et al., Fibromyalgia 
Syndrome:  Canadian Clinical Working Case Definition, Diagnostic and Treatment 
Protocols—A Consensus Document, 11 J. Musculoskeletal Pain 3, 44 (2003) 
(“There is strong consistency in documentation that physical trauma such as a fall 
or motor vehicle accident, particularly a whiplash or spinal injury, can trigger FMS 
in some patients.”); Samuel A. McLean et al., Fibromyalgia After Motor Vehicle 
Collision: Evidence and Implications, 6 Traffic Injury Prevention 97, 99 (2005) 
(“There is no disagreement regarding a close temporal association between [a 
motor vehicle collision] and the development of [fibromyalgia].”); Roland Staud, 
Fibromyalgia Pain:  Do We Know the Source?, 16 Current Opinion in 
Rheumatology, 157, 158 (March 2004) (recognizing physical trauma as one of the 
“triggers” associated with fibromyalgia); Muhammad B. Yunus et al., 
Fibromyalgia Consensus Report:  Additional Comments, 3 J. Clinical 
Rheumatology 324, 325 (1997) (“[I]t seems more than 51% likely that trauma does 
play a causative role in some FMS patients . . . .”). 
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Frye does not require unanimity.  Brim, 695 So. 2d at 272.  While the 
precise etiology of fibromyalgia may not be fully understood, we hold that Marsh 
has sufficiently demonstrated the reliability of her experts’ testimony, and the trial 
court erred in excluding it. See Berry, 709 So. 2d at 568 (“While . . . there 
continues to be scientific debate . . . we find the epidemiological science and 
methodology underlying [the expert’s] testimony to be established, reliable, and 
well-founded.”). 
III. CONCLUSION 
For the reasons explained above, we hold that Frye does not apply to expert 
testimony causally linking trauma to fibromyalgia.  We further hold that, even if 
applicable, the testimony satisfies Frye. Therefore, we quash the Fifth District’s 
decision in Marsh, 917 So. 2d at 313, and approve the Second District’s conflicting 
decision in Johnson, 880 So. 2d at 721. 
It is so ordered. 
LEWIS, C.J., and ANSTEAD, PARIENTE, and QUINCE, JJ., concur. 
ANSTEAD, J., specially concurs with an opinion, in which PARIENTE, J., 
concurs. 
CANTERO, J., dissents with an opinion, in which WELLS and BELL, JJ., concur. 
NOT FINAL UNTIL TIME EXPIRES TO FILE REHEARING MOTION, AND 
IF FILED, DETERMINED. 
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ANSTEAD, J., specially concurring. 
I concur in the majority’s holding that the expert opinion evidence in 
question was admissible.  However, I do so not only for the reasons set out in the 
majority opinion, but also on my belief the Frye standard did not survive the 
adoption of Florida’s Evidence Code.   
While this Court has continued to apply Frye in determining the 
admissibility of scientific expert opinion testimony after the adoption of the Florida 
Rules of Evidence, it has done so without confronting the fact that those rules do 
not mention Frye or the test set out in Frye. Hence, unlike the United States 
Supreme Court, we have never explained how Frye has survived the adoption of 
the rules of evidence. Because, like the United States Supreme Court, I find no 
basis for concluding that Frye has survived Florida’s adoption of an evidence code 
similar to the federal code, I would recede from our cases continuing to apply Frye 
and hold that the rules of evidence do not include a Frye test for determining the 
admission of expert testimony.  In fact, the adoption of these evidence codes was 
intended to apply a straightforward relevancy test to expert evidence and, in 
essence, to establish a rule favoring admissibility once relevancy was established, 
while leaving it to the fact-finder to determine the credibility and weight of such 
evidence. 
DAUBERT 
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As the United States Supreme Court explained in its seminal decision in 
Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579, 585-89 (1993): 
In the 70 years since its formulation in the Frye case, the 
“general acceptance” test has been the dominant standard for 
determining the admissibility of novel scientific evidence at trial.  See 
E. Green & C. Nesson, Problems, Cases, and Materials on Evidence 
649 (1983). Although under increasing attack of late, the rule 
continues to be followed by a majority of courts, including the Ninth 
Circuit. [n.3] 
[N.3.] For a catalog of the many cases on either side of 
this controversy, see P. Giannelli & E. Imwinkelried, 
Scientific Evidence § 1-5, pp. 10-14 (1986 and Supp. 
1991). 
The Frye test has its origin in a short and citation-free 1923 
decision concerning the admissibility of evidence derived from a 
systolic blood pressure deception test, a crude precursor to the 
polygraph machine. In what has become a famous (perhaps 
infamous) passage, the then Court of Appeals for the District of 
Columbia described the device and its operation and declared:  
“Just when a scientific principle or discovery crosses the 
line between the experimental and demonstrable stages is 
difficult to define. Somewhere in this twilight zone the 
evidential force of the principle must be recognized, and 
while courts will go a long way in admitting expert 
testimony deduced from a well-recognized scientific 
principle or discovery, the thing from which the 
deduction is made must be sufficiently established to 
have gained general acceptance in the particular field in 
which it belongs.” 54 App. D.C., at 47, 293 F., at 1014 
(emphasis added).  
Because the deception test had “not yet gained such standing and 
scientific recognition among physiological and psychological 
authorities as would justify the courts in admitting expert testimony 
deduced from the discovery, development, and experiments thus far 
made,” evidence of its results was ruled inadmissible.  Ibid. 
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The merits of the Frye test have been much debated, and 
scholarship on its proper scope and application is legion. [n.4]  
Petitioners’ primary attack, however, is not on the content but on the 
continuing authority of the rule.  They contend that the Frye test was 
superseded by the adoption of the Federal Rules of Evidence.  [n.5] 
We agree. 
[N.4.] See, e.g., Green, Expert Witnesses and 
Sufficiency of Evidence in Toxic Substances Litigation:  
The Legacy of Agent Orange and Bendectin Litigation, 
86 Nw. U. L. Rev. 643 (1992) (hereinafter Green); 
Becker & Orenstein, The Federal Rules of Evidence 
After Sixteen Years––the Effect of “Plain Meaning” 
Jurisprudence, the Need for an Advisory Committee on 
the Rules of Evidence, and Suggestions for Selective 
Revision of the Rules, 60 Geo. Wash. L. Rev. 857, 876­
885 (1992); Hanson, James Alphonzo Frye is Sixty-Five 
Years Old; Should He Retire?, 16 West. St. U. L. Rev. 
357 (1989); Black, A Unified Theory of Scientific 
Evidence, 56 Ford. L. Rev. 595 (1988); Imwinkelried, 
The “Bases” of Expert Testimony:  The Syllogistic 
Structure of Scientific Testimony, 67 N.C.L.Rev. 1 
(1988); Proposals for a Model Rule on the Admissibility 
of Scientific Evidence, 26 Jurimetrics J. 235 (1986); 
Giannelli, The Admissibility of Novel Scientific 
Evidence: Frye v. United States, a Half-Century Later, 80 
Colum. L. Rev. 1197 (1980); The Supreme Court, 1986 
Term, 101 Harv. L. Rev. 7, 119, 125-127 (1987).  
Indeed, the debates over Frye are such a well-
established part of the academic landscape that a distinct 
term––“Frye-ologist”––has been advanced to describe 
those who take part. See Behringer, Introduction, 
Proposals for a Model Rule on the Admissibility of 
Scientific Evidence, 26 Jurimetrics J. 237, 239 (1986), 
quoting Lacey, Scientific Evidence, 24 Jurimetrics J. 254, 
264 (1984). 
[N.5]. Like the question of Frye’s merit, the 
dispute over its survival has divided courts and 
commentators.  Compare, e.g., United States v. Williams, 
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583 F.2d 1194 (CA2 1978) (Frye is superseded by the 
Rules of Evidence), cert. denied, 439 U.S. 1117 (1979), 
with Christophersen v. Allied-Signal Corp., 939 F.2d 
1106, 1111, 1115-1116 (CA5 1991) (en banc) (Frye and 
the Rules coexist), cert. denied, 503 U.S. 912 (1992), 3 J. 
Weinstein & M. Berger, Weinstein’s Evidence ¶ 702[03], 
pp. 702-36 to 702-37 (1988) (hereinafter Weinstein & 
Berger) (Frye is dead), and M. Graham, Handbook of 
Federal Evidence § 703.2 (3d ed. 1991) (Frye lives). See 
generally P. Giannelli & E. Imwinkelried, Scientific 
Evidence § 1-5, at 28-29 (citing authorities). 
We interpret the legislatively enacted Federal Rules of 
Evidence as we would any statute. Beech Aircraft Corp. v. Rainey, 
488 U.S. 153, 163 (1988). Rule 402 provides the baseline: 
“All relevant evidence is admissible, except as otherwise 
provided by the Constitution of the United States, by Act 
of Congress, by these rules, or by other rules prescribed 
by the Supreme Court pursuant to statutory authority.  
Evidence which is not relevant is not admissible.”  
“Relevant evidence” is defined as that which has “any tendency to 
make the existence of any fact that is of consequence to the 
determination of the action more probable or less probable than it 
would be without the evidence.” Rule 401.  The Rule’s basic standard 
of relevance thus is a liberal one. 
Frye, of course, predated the Rules by half a century.  In United 
States v. Abel, 469 U.S. 45 (1984), we considered the pertinence of 
background common law in interpreting the Rules of Evidence.  We 
noted that the Rules occupy the field, id., at 49, but, quoting Professor 
Cleary, the Reporter, explained that the common law nevertheless 
could serve as an aid to their application:  
“ ‘In principle, under the Federal Rules no common law 
of evidence remains. “All relevant evidence is 
admissible, except as otherwise provided . . . .”  In 
reality, of course, the body of common law knowledge 
continues to exist, though in the somewhat altered form 
- 19 ­
 
 
 
 
 
 
 
of a source of guidance in the exercise of delegated 
powers.’ ” Id., at 51-52. 
We found the common-law precept at issue in the Abel case entirely 
consistent with Rule 402’s general requirement of admissibility, and 
considered it unlikely that the drafters had intended to change the rule. 
Id., at 50-51. In Bourjaily v. United States, 483 U.S. 171 (1987), on 
the other hand, the Court was unable to find a particular common-law 
doctrine in the Rules, and so held it superseded. 
Here there is a specific Rule that speaks to the contested issue.  
Rule 702, governing expert testimony, provides:  
“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 thereto in the form of 
an opinion or otherwise.” 
Nothing in the text of this Rule establishes “general acceptance” as an 
absolute prerequisite to admissibility.  Nor does respondent present 
any clear indication that rule 702 or the Rules as a whole were 
intended to incorporate a “general acceptance” standard.  The drafting 
history makes no mention of Frye, and a rigid “general acceptance” 
requirement would be at odds with the “liberal thrust” of the Federal 
Rules and their “general approach of relaxing the traditional barriers 
to ‘opinion’ testimony.” Beech Aircraft Corp. v. Rainey, 488 U.S., at 
169 (citing Rules 701 to 705). See also Weinstein, Rule 702 of the 
Federal Rules of Evidence is Sound; It Should Not Be Amended, 138 
F.R.D. 631 (1991) (“The Rules were designed to depend primarily 
upon lawyer-adversaries and sensible triers of fact to evaluate 
conflicts”). Given the Rules’ permissive backdrop and their inclusion 
of a specific rule on expert testimony that does not mention “general 
acceptance,” the assertion that the Rules somehow assimilated Frye is 
unconvincing.  Frye made “general acceptance” the exclusive test for 
admitting expert scientific testimony.  That austere standard, absent 
from, and incompatible with, the Federal Rules of Evidence, should 
not be applied in federal trials. [n.6] 
- 20 ­
 
 
 
 
 
 
                                          
 
 
 
[N.6.] Because we hold that Frye has been 
superseded and base the discussion that follows on the 
content of the congressionally enacted Federal Rules of 
Evidence, we do not address petitioners’ argument that 
application of the Frye rule in this diversity case, as the 
application of a judge-made rule affecting substantive 
rights, would violate the doctrine of Erie R. Co. v. 
Tompkins, 304 U.S. 64 (1938). 
509 U.S. at 585-89 (emphasis supplied).  Hence, a unanimous United States 
Supreme Court concluded that Frye’s “austere standard, absent from, and 
incompatible with, the Federal Rules of Evidence, should not be applied in federal 
trials.” Id. at 589. This Court should reach the same conclusion for Florida.4 
FLORIDA’S EVIDENCE CODE 
Of course, Florida’s Evidence Code is patterned substantially upon the 
Federal Rules of Evidence. Section 90.702 of Florida’s code is essentially 
identical to Federal Rule 702. And, to paraphrase the United States Supreme 
Court’s opinion in Daubert, nothing in section 90.702 or elsewhere in Florida’s 
Evidence Code establishes “general acceptance” as a prerequisite to the 
admissibility of expert opinion evidence.  Indeed, such a rigid test is at odds with 
both the Florida code and “ ‘the liberal thrust’ of the [code] . . . and . . . [its] 
4. While I agree with the Supreme Court’s analysis in Daubert rejecting 
Frye’s viability after the evidence code was adopted, I also agree with the separate 
opinion of Chief Justice Rehnquist that the balance of the majority’s opinion was 
unnecessary. See Daubert, 509 U.S. at 598 (Rehnquist, C.J., concurring in part and 
dissenting in part). Hence, while I would conclude that Frye no longer controls, I 
would apply the relevancy standard set out in Florida’s Evidence Code to 
determine whether expert opinion evidence should be admitted.  
- 21 ­
 
 
 
 
‘general approach of relaxing the traditional barriers to “opinion” testimony.’ ”  
509 U.S. at 589 (quoting Beech, 488 U.S. at 169). 
Daubert was decided in 1993, years after the adoption of both the federal 
rules and the Florida Evidence Code. However, following the adoption of 
Florida’s Evidence Code a number of Florida appellate decisions came to the same 
conclusion as the Supreme Court in Daubert, years before Daubert was decided. 
And, while this Court has clung to its reliance upon Frye, no opinion of the Court 
has ever confronted or explained how Frye is consistent with the provisions of 
Florida’s Evidence Code. The plain fact is, as fully and cogently explained by the 
United States Supreme Court in Daubert, Frye is not consistent with Florida’s 
code. 
While this Court has never directly confronted the issue, the district courts 
have discussed the tension between Frye and the terms of the Evidence Code, and 
reached the same conclusion the United States Supreme Court later reached in 
Daubert. See, e.g., Brown v. State, 426 So. 2d 76 (Fla. 1st DCA 1983). In Brown, 
the First District explained: 
The relevancy approach [of the Evidence Code] is preferred 
over the Frye rule because of problems inherent in the application of 
Frye and due to policy reasons. See Giannelli, supra. One of the 
major criticisms directed against applying the Frye rule to a given 
scientific technique is that it would indiscriminately bar the 
admissibility of such evidence despite whether it meets the twin tests 
of logical and legal relevance.  For example, as pointed out by 
- 22 ­
 
 
 
 
 
 
Professor Giannelli, a rigid application of Frye would require a court 
to await the passage of time until such time as a new test or procedure 
has been developed to the point that the test or procedure has been 
developed to the point that the test or procedure has become 
“generally accepted.” This creates a “cultural lag” during the 
technique’s development, requiring that relevant evidence which 
might be demonstrated to be completely reliable must be excluded 
from consideration.  See Giannelli, supra, at 1223 nn. 201 & 202; 
contrast United States v. Addison, 498 F.2d 741, 743-744 (D.C. Cir. 
1974). Plainly, the Frye rule engenders an impediment to the 
admissibility of reliable evidence without considering the cost to 
society. Admissibility of Testimony Influenced by Hypnosis, supra, 
67 Va. L. Rev. at 1214, n. 77; see also Hurd, 432 A.2d at 94. 
Brown, 426 So. 2d at 87 n.17. In addition, the Brown opinion quoted 
McCormick’s Handbook of the Law of Evidence § 203 (Edward W. Cleary ed., 
2nd ed. 1972): 
The practice approved in the last mentioned case [Coppolino] is 
the one which should be followed in respect to expert testimony and 
scientific evidence generally. “General scientific acceptance” is a 
proper consideration for taking judicial notice of scientific facts, but 
not a criterion for the admissibility of scientific evidence.  Any 
relevant conclusions which are supported by a qualified expert 
witness should be received unless there are other reasons for 
exclusion. Particularly, probative value may be overborne by the 
familiar dangers of prejudicing or misleading the jury, and undue 
consumption of time.  If the courts used this approach, instead of 
repeating a supposed requirement of “general acceptance” not 
elsewhere imposed, they would arrive at a practical way of utilizing 
the results of scientific advances. 
Brown, 426 So. 2d at 88 (quoting McCormick, § 203). 
In Hawthorne v. State, 470 So. 2d 770 (Fla. 1st DCA 1985), the First 
District, without a mention of Frye, found no error in the trial court’s exclusion of 
- 23 ­
 
 
 
 
 
 
 
an expert witness’s testimony without prejudice to the reconsideration of that issue 
upon retrial.  In a separate opinion, however, Judge Ervin provided an extensive 
and scholarly analysis concluding that the Frye test did not survive the adoption of 
Florida’s Evidence Code.  470 So. 2d at 774 (Ervin, C.J., concurring in part and 
dissenting in part). I commend Judge Ervin’s compelling analysis to the reader 
and quote here only his concluding remarks: 
It is time for the judiciary system to recognize that the Evidence 
Code establishes a different standard in assessing the admissibility of 
novel scientific theories or techniques than does Frye. Their 
admissibility is not dependent solely upon proof that they have not 
generally been accepted by the relevant field––although lack of 
general acceptance, when balanced against all counterweights, 
pursuant to section 90.403, is clearly a component to be considered in 
determining whether the probative value of such evidence is 
substantially outweighed by countervailing factors.  If the challenged 
evidence, such as that in the present case, is logically relevant, and if 
balancing does not reveal it to be substantially outweighed by the 
factors enumerated in section 90.403, the trial judge should tip his 
hand in favor of admissibility. 
Had the trial court below been appropriately directed to follow 
the procedure that appears to be required by the Evidence Code, and if 
it had nevertheless exercised its discretion to exclude, such decision 
would have constituted an abuse of discretion.  The weight and quality 
of the evidence clearly demonstrate that Dr. Walker's proffered 
testimony should have been admitted––particularly when it is 
considered that such evidence was crucial to appellant's claim of self-
defense. [n.10] 
[N.10.] A trial court's denial of a defendant's use of 
probative evidence in a criminal trial may rise to the level 
of constitutional dimension. Although a defendant has 
no constitutional right to introduce irrelevant evidence, if 
the evidence has probative worth, it should be measured 
by a different standard than the usual test of abuse of 
- 24 ­
 
 
 
 
 
discretion.  See State v. Dorsey, 87 N.M. 323, 532 P.2d 
912 (Ct. App.); aff’d, 88 N.M. 184, 539 P.2d 204 (1975).  
See also Westen, The Compulsory Process Clause, 73 
Mich. L. Rev. 73, 149-59 (1974). Cf. United States v. 
Dwyer, 539 F.2d 924, 928 (2nd Cir.1976) (trial court 
erred in excluding the testimony of the only defense 
witness who could establish the insanity of defendant). 
Today's opinion points out the need for a definitive statement 
from the Florida Supreme Court defining the respective roles of the 
trial and appellate courts, when carrying out their responsibilities 
under the Florida Evidence Code, in determining the admissibility of 
new scientific theories or techniques.  Pursuant to Florida Rule of 
Appellate Procedure 9.030(a)(2)(A)(v), I would certify the following 
question to be one of great public importance:  
HAS THE FRYE STANDARD OF GENERAL 
ACCEPTANCE WITHIN THE PARTICULAR 
SCIENTIFIC COMMUNITY, AS A PRECONDITION 
TO THE ADMISSIBILITY OF NOVEL SCIENTIFIC 
EVIDENCE, SURVIVED THE ADOPTION OF THE 
FLORIDA EVIDENCE CODE?  AND IF IT HAS NOT, 
DOES IT NEVERTHELESS REMAIN A FACTOR TO 
BE CONSIDERED WHEN BALANCING THE 
PROBATIVE WORTH OF THE PROFFERED 
EVIDENCE AGAINST COUNTERVAILING 
FACTORS, AS PROVIDED BY SECTION 90.403, 
FLORIDA STATUTES? 
470 So. 2d at 787-88.  Unfortunately, Hawthorne was not reviewed by this Court, 
and, although this Court has subsequently rejected Daubert in favor of Frye, Judge 
Ervin’s proposed question has never been properly answered by this Court other 
than in summary fashion.  See, e.g., Ibar v. State, 938 So. 2d 451, 467 (Fla. 2006) 
(summarily stating Florida adheres to Frye despite ruling in Daubert), cert. denied, 
127 S. Ct. 1326 (2007). 
- 25 ­
 
 
 
 
 
 
 
Following the Hawthorne decision, the Fourth District, in Kruse v. State, 
483 So. 2d 1383 (Fla. 4th DCA 1986), followed Judge Ervin’s lead in concluding 
that Florida’s Evidence Code, and not Frye, should control the admission of expert 
opinion evidence: 
The Florida Evidence Code became effective in criminal cases 
in 1979. Sections 90.401 and 90.402, Florida Statutes (1983), set out 
a general relevancy standard for the admission of evidence.  Sections 
90.702 and 90.703 deal specifically with expert testimony:  
90.702 Testimony by experts.––If scientific, 
technical, or other specialized knowledge will assist the 
trier of fact in understanding the evidence or in 
determining a fact in issue, a witness qualified as an 
expert by knowledge, skill, experience, training, or 
education may testify about it in the form of an opinion; 
however, the opinion is admissible only if it can be 
applied to evidence at trial. 
90.703 Opinion on ultimate issue.––Testimony in 
the form of an opinion or inference otherwise admissible 
is not objectionable because it includes an ultimate issue 
to be decided by the trier of fact. 
In addition, section 90.403 provides: 
90.403 Exclusion on grounds of prejudice or 
confusion.––Relevant evidence is inadmissible if its 
probative value is substantially outweighed by the danger 
of unfair prejudice, confusion of issues, misleading the 
jury, or needless presentation of cumulative evidence.  
This section shall not be construed to mean that evidence 
of the existence of available third-party benefits is 
inadmissible. 
Section 90.702 contains three requirements: (1) that the opinion 
evidence be helpful to the trier of fact; (2) that the witness be qualified 
as an expert; and (3) that the opinion evidence can be applied to 
evidence offered at trial. These provisions embody a liberal policy on 
- 26 ­
 
 
 
 
the admission of expert evidence, generally rendering such evidence 
admissible to the extent that it is helpful to the trier of fact.  Section 
90.403 adds a fourth test barring evidence that, although technically 
relevant, presents a substantial danger of unfair prejudice that 
outweighs its probative value. 
In Brown v. State, 426 So. 2d 76 (Fla. 1st DCA 1983), Judge 
Ervin discussed the evolution in Florida decisions, from a rigid test of 
admissibility of evidence relating to new scientific procedures, to the 
more generous relevancy standard contained in the evidence code.  Id. 
at 85-90; see also Fay v. Mincey, 454 So. 2d 587, 593-94 (Fla. 2d 
DCA 1984), and Hawthorne v. State, 470 So. 2d 770 (Fla. 1st DCA 
1985) (Ervin, J., concurring in part and dissenting in part).  The more 
rigid standard evolved from the decision in Frye v. United States, 293 
Fed. 1013 (D.C. Cir. 1923), which barred the admission of the results 
of a lie detector test because the test had not been generally accepted 
by the scientific community.  Hence, the requirement of general 
acceptance was imposed.  As Judge Ervin noted in his partial dissent 
in Hawthorne, the evidence code contains no reference to general 
acceptance in regard to the receipt of expert opinion evidence. 
With some qualification, we believe the relevancy approach set 
out in the evidence code is the appropriate standard for determining 
the admissibility of expert testimony on child sexual abuse.  The 
statutory relevancy standard also comports with the holdings of the 
Florida Supreme Court in the area of expert testimony.  The court has 
stated that while trial courts have broad discretion in determining the 
range of subjects on which an expert may testify, such testimony 
should usually be received only where the disputed issue for which 
the evidence is offered, is beyond the ordinary understanding of the 
jury. Johnson v. State, 393 So. 2d 1069, 1072 (Fla. 1980). This view 
is consistent with the first requirement of section 90.702, that the 
opinion evidence be helpful to the trier of fact, as well as the 
provisions of section 90.403, that the danger of prejudice may 
outweigh the value of the evidence. 
- 27 ­
 
 
 
 
                                          
 
 
 
 
 
483 So. 2d at 1384-85.5  Despite the numerous district court decisions finding Frye 
superseded by the Evidence Code, this Court subsequently announced in summary 
fashion its continued reliance on Frye, while not directly confronting the impact of 
the application of the Evidence Code to the issue.  See Ibar, 938 So. 2d at 467. I 
would recede from those decisions for the same reasons articulated in Daubert, 
Brown, Hawthorne and Kruse.6 
THIS CASE 
There are courts that have addressed the exact question of expert testimony 
linking physical trauma to fibromyalgia and found it admissible pursuant to the 
rule announced in Daubert. For example, in Reichert v. Phipps, 84 P.3d 353 (Wyo. 
2004), the Wyoming Supreme Court reversed a trial court’s order prohibiting the 
plaintiff from offering evidence that the car crash at issue in the case caused her 
fibromyalgia.  Id. at 355. The court framed its analysis as follows:   
5. The Fourth District subsequently affirmed its position that the Evidence 
Code contained a four-part test as outlined in Kruse for determining the 
admissibility of expert opinion evidence.  See CSX Transp., Inc. v. Whittler, 584 
So. 2d 579, 584 (Fla. 4th DCA 1991). 
6. A part of our Frye law that is particularly troubling is our direction to 
appellate courts that they are not only to conduct a de novo review of the general 
acceptance issue but they should also examine any extrajudicial materials available 
at the time of appeal to resolve the issue.  Hadden v. State, 690 So. 2d 573, 579 
(Fla. 1997). Of course, any such materials considered by the appellate court would 
not have been subject to cross-examination or other examination for reliability by 
the parties or the trial court. Such a novel procedure represents a significant break 
from our established law limiting appellate courts to a consideration of the trial 
record. 
- 28 ­
 
 
 
 
 
We are not deciding whether trauma can cause [fibromyalgia], or even 
whether, as a general proposition, there is sufficient scientific 
foundation for the theory to allow juries to decide the issue as a 
question of fact. . . . The question before us is limited to whether this 
particular trial court, given the evidence and arguments at the time, 
reasonably could have concluded as it did. 
Id. at 357. In finding that the trial court abused its discretion in excluding the 
evidence, the court found that, since some experts do believe that trauma can cause 
fibromyalgia, the proffered expert had reliable grounds for reaching such a 
conclusion and that therefore his opinion was admissible.  Id. at 364 (emphasis 
added). 
In the instant case, the proffered expert opinions were based on the 
petitioner’s self-reported symptoms, filtered through the two doctors’ 
perceptions after years of experience with similar patients. The opinions 
were given in the overall context of a professional controversy over the link 
between physical trauma and FM, in which some experts take the position 
that there is, indeed, a causal connection. We conclude that, under these 
circumstances, the trial court abused its discretion in not allowing the jury to 
determine the weight to give the opinion testimony. 
Id. 
The Nebraska Supreme Court reached a similar conclusion in Epp v. Lauby, 
715 N.W.2d 501, 504 (Neb. 2006), involving an action for damages in which the 
plaintiff allegedly developed fibromyalgia after a car accident.  The trial court 
conducted a Daubert hearing concerning Epp’s expert testimony that the accident 
caused the fibromyalgia, and the trial court excluded the evidence, concluding that 
medical science was insufficient to link the trauma to the condition.  Id. at 506. 
Under an abuse of discretion standard, the supreme court overturned the trial 
- 29 ­
 
 
 
   
 
court’s ruling on the expert testimony after phrasing the question as follows:  
“[W]e are deciding whether there was sufficient evidence presented to allow Epp’s 
experts, Handke and Bennett, to opine that physical trauma was the cause of Epp’s 
fibromyalgia.”  Id. at 507. The court, noting the “professional controversy 
regarding the causal relationship between physical trauma and fibromyalgia,” 
ultimately concluded that “general acceptance of the causal link . . . is not 
determinative of the admissibility of expert testimony under Daubert/Schafersman 
standards.” Id. at 509-10. “So long as the expert’s opinion is based on reliable 
methodology, his or her opinion is admissible, whether or not the court agrees with 
the expert’s conclusion.” Id. at 510. The court found that the experts’ testimony 
was supported by sufficient medical and scientific literature supporting the theory 
that fibromyalgia may be caused by physical trauma.  Id. 
Although the issue is disputed, there is support in the medical 
literature for the theory that physical trauma can cause fibromyalgia.  
That support, while controverted, is the result of peer-reviewed 
research conducted pursuant to appropriate methods of scientific 
inquiry.  While there is not a sufficient scientific consensus to say that 
the theory is generally accepted, nor has a rate of error been 
established, the theory that trauma can cause fibromyalgia has been 
the subject of empirical research, the results of which have been 
subjected to peer review and publication. See Daubert v. Merrell 
Dow Pharmaceuticals, Inc., supra. We cannot conclude that Handke 
and Bennett’s reliance on this research, instead of literature to the 
contrary, was methodologically unreliable.  If proffered scientific 
evidence rests on sound scientific reasoning or methodology and 
properly can be applied to the facts in issue, it meets the Daubert 
requirements for admissibility, even if the conclusion is novel or 
controversial. See State v. Dahood, supra. Despite the existence of 
- 30 ­
 
 
 
 
 
 
 
 
 
 
 
“spirited dissent,” see State v. Sampson, 167 Or. App. at 503, 6 P.3d 
at 553, the lack of a scientific consensus on the link between trauma 
and fibromyalgia was not sufficient to render reliance upon that 
literature methodologically unreliable.  We, therefore, conclude that 
the evidence was sufficient to support the theory of a causal 
relationship between physical trauma and fibromyalgia and that the 
trial court abused its discretion in concluding otherwise. 
Id. at 511. Accordingly, the supreme court remanded for a new trial on the issue of 
damages, since liability in the case was admitted.  Id. at 512. 
CONCLUSION 
I would hold that Frye has been superseded by the adoption of Florida’s 
Evidence Code, and that under the relevancy standard contained in the code the 
expert opinion evidence in question was admissible.  Hence, I concur in the 
majority’s decision. 
PARIENTE, J., concurs. 
CANTERO, J., dissenting. 
I respectfully disagree with the majority’s holding that testimony causally 
linking trauma to fibromyalgia is “pure opinion” testimony not subject to the Frye 
test. I also disagree that such testimony would satisfy Frye. I would approve the 
Fifth District’s opinion in Marsh v. Valyou, 917 So. 2d 313 (Fla. 5th DCA 2005), 
and disapprove the Second District’s conflicting decision in State Farm Mutual 
Automobile Insurance Co. v. Johnson, 880 So. 2d 721 (Fla. 2d DCA 2004). 
- 31 ­
 
 
 
 
 
Below I demonstrate (I) why expert testimony causally linking trauma to 
fibromyalgia must satisfy Frye, and (II) that Petitioner, as the proponent of the 
evidence, has failed to demonstrate that it is generally accepted in the scientific 
community that trauma can cause fibromyalgia. 
I. THE TESTIMONY IS SUBJECT TO FRYE 
The Frye test is simple to state, if not always easy to apply: “[I]n order to 
introduce expert testimony deduced from a scientific principle or discovery, the 
principle or discovery ‘must be sufficiently established to have gained general 
acceptance in the particular field in which it belongs.’”  Flanagan v. State, 625 So. 
2d 827, 828 (Fla. 1993) (quoting Frye v. United States, 293 F. 1013, 1014 (D.C. 
Cir. 1923)). “This standard requires a determination, by the judge, that the basic 
underlying principles of scientific evidence have been sufficiently tested and 
accepted by the relevant scientific community.”  Brim v. State, 695 So. 2d 268, 
272 (Fla. 1997); see also Ramirez v. State, 810 So. 2d 836, 843 (Fla. 2001) 
(“Evidence based on a novel scientific theory is inherently unreliable and 
inadmissible in a legal proceeding in Florida unless the theory has been adequately 
tested and accepted in the relevant scientific community.”).  The underlying theory 
of Frye is that “a courtroom is not a laboratory, and as such it is not the place to 
conduct scientific experiments. If the scientific community considers a procedure 
or process unreliable for its own purposes, then the procedures must be considered 
- 32 ­
 
 
 
 
  
 
less reliable for courtroom use.”  Stokes v. State, 548 So. 2d 188, 193-94 (Fla. 
1989). 
A. Novel Scientific Testimony Versus “Pure Opinion” 
Courts traditionally have exempted pure opinion testimony from the 
requirements of Frye on the theory that the testimony is based on the expert’s 
personal experience and training.  See, e.g., Hadden v. State, 690 So. 2d 573, 580 
(Fla. 1997); Flanagan, 625 So. 2d at 828; State v. Demeniuk, 888 So. 2d 655, 659 
(Fla. 5th DCA 2004). As we explained in Flanagan: 
[P]ure opinion testimony, such as an expert’s opinion that a defendant 
is incompetent, does not have to meet Frye, because this type of 
testimony is based on the expert’s personal experience and training.  
While cloaked with the credibility of the expert, this testimony is 
analyzed by the jury as it analyzes any other personal opinion or 
factual testimony by a witness. 
625 So. 2d at 828. The majority holds that testimony causally linking trauma to 
fibromyalgia is just such “pure opinion” testimony.  This conclusion broadens this 
supposedly narrow exception way beyond its limited purpose. 
Testimony is “pure opinion” only when it is based solely on experience and 
training, and does not rely on a novel scientific principle, test, or methodology: 
“Pure opinion” refers to expert opinion developed from inductive 
reasoning based on the experts’ own experience, observation, or 
research, whereas the Frye test applies when an expert witness reaches 
a conclusion by deduction, from applying new and novel scientific 
principle, formula, or procedure developed by others. 
- 33 ­
 
 
 
 
 
Demeniuk, 888 So. 2d at 659 (quoting Holy Cross Hosp., Inc. v. Marrone, 816 So. 
2d 1113, 1117 (Fla. 4th DCA 2001)). We first recognized that pure opinion 
testimony is not subject to Frye in Flanagan, 625 So. 2d at 828. There, we 
recognized the distinction between pure opinion testimony derived solely from 
“experience and training” and expert testimony that “necessarily relies on some 
scientific principle or test” and rejected labeling the pedophile/sex offender profile 
testimony at issue “pure opinion”:  
Profile testimony . . . by its nature necessarily relies on some scientific 
principle or test, which implies an infallibility not found in pure 
opinion testimony.  The jury will naturally assume that the scientific 
principles underlying the expert’s conclusion are valid.  Accordingly, 
this type of testimony must meet the Frye test, designed to ensure that 
the jury will not be misled by experimental scientific methods which 
may ultimately prove to be unsound. 
Id. Similarly, in Hadden, 690 So. 2d at 581, we applied Frye to testimony that an 
alleged victim of sexual abuse exhibited symptoms consistent with those of a child 
who has been sexually abused. We explained that the Frye test “requires that the 
scientific principles undergirding this evidence be found by the trial court to be 
generally accepted by the relevant members of its particular field.”  Hadden, 690 
So. 2d at 576. We rejected labeling the evidence “pure opinion”: 
We differentiate pure opinion testimony based upon clinical 
experience from profile and syndrome evidence because profile and 
syndrome evidence rely on conclusions based upon studies and tests.  
Further, we find that profile or syndrome evidence is not made 
admissible by combining such evidence with pure opinion testimony 
- 34 ­
 
 
 
 
 
 
because such a combination is not pure opinion evidence based solely 
upon the expert’s clinical experience. 
Id. at 580 (emphasis added).   
Therefore, in both Flanagan and Hadden we recognized that pure opinion is 
not subject to Frye, but emphasized that the underlying scientific principles are. 
Flanagan, 625 So. 2d 828; Hadden, 690 So. 2d at 576, 580; see also Brim, 695 
So. 2d 272 (recognizing that under Frye, “the burden is on the proponent of the 
evidence to prove the general acceptance of both the underlying scientific principle 
and the testing procedures used to apply that principle to the facts at hand”) 
(quoting Ramirez v. State, 651 So. 2d 1164, 1168 (Fla. 1995)). 
These cases dictate that where an expert’s opinion is based on an underlying 
scientific principle, that underlying principle is subject to Frye. See also Hildwin 
v. State, 951 So. 2d 784, 792 (Fla. 2006) (“The principal inquiry under the Frye 
test is whether the scientific theory or discovery from which an expert derives an 
opinion is reliable.”) (quoting Ramirez, 651 So. 2d at 1167). 
In this case, the underlying scientific principle is that trauma can cause 
fibromyalgia.  That principle must pass the Frye test. I agree that testimony that a 
particular patient, such as Marsh, suffers from fibromyalgia, if based on clinical 
experience, may constitute pure opinion not subject to Frye. In this case, however, 
the objection was not to testimony that Marsh suffers from fibromyalgia, but to 
testimony that it was caused by trauma.  While the experts may assert that their 
- 35 ­
 
 
 
testimony is based on their experience and training, it is also necessarily based on 
an underlying (and as yet unproven) scientific principle that trauma can cause 
fibromyalgia.  Marsh, 917 So. 2d at 327 (recognizing that the testimony requires 
“an underlying scientific assumption—that trauma can cause fibromyalgia—which 
is not involved in pure opinion cases”); see also Kaelbel Wholesale, Inc. v. 
Soderstrom, 785 So. 2d 539, 547 (Fla. 4th DCA 2001) (rejecting the argument that 
causation testimony was pure opinion, concluding that it “was not based upon 
personal experience or training” but instead “was based upon scientific principles 
to reach the opinions and conclusions drawn”).  This theory of general causation 
does not become admissible simply because it is the opinion of some experts that 
trauma caused Marsh’s fibromyalgia.  See Hadden, 690 So. 2d at 580 (recognizing 
that evidence is not made admissible by combining it with “pure opinion” 
testimony); Marsh, 917 So. 2d at 327 (“[I]t is counterintuitive to permit an expert 
to ignore scientific literature accepted by the general scientific community in favor 
of the expert’s personal experience to reach a conclusion not generally recognized 
in the scientific community and then allow testimony about that conclusion on the 
basis that it is ‘pure opinion.’”).  As we recognized in Hadden: 
Novel scientific evidence must also be shown to be reliable on some 
basis other than simply that it is the opinion of the witness who seeks 
to offer the opinion. In sum, we will not permit factual issues to be 
resolved on the basis of opinions which have yet to achieve general 
acceptance in the relevant scientific community; to do otherwise 
would permit resolutions based upon evidence which has not been 
- 36 ­
 
 
 
 
 
 
 
 
demonstrated to be sufficiently reliable and would thereby cast doubt 
on the reliability of the factual resolutions. 
690 So. 2d at 578; see also Ramirez, 810 So. 2d at 844 (recognizing that Frye 
requires more than “[a] bald assertion by the expert that his deduction is premised 
upon well-recognized scientific principles”).   
The majority’s holding that an opinion about specific causation need not 
pass the Frye test, even where the underlying theory of general causation is not 
accepted, in effect renders specific causation testimony always admissible as the 
“pure opinion” of the expert.  This constitutes a sea change in Florida law, as 
Florida courts have regularly applied Frye to causation testimony. See, e.g., 
Shepard v. Barnard, 949 So. 2d 232, 233 (Fla. 5th DCA 2007) (applying Frye to 
testimony that the use of Verteporfin could cause permanent photoallergy); 
Hawkins v. State, 933 So. 2d 1186, 1189 (Fla. 4th DCA 2006) (finding Frye 
applicable to an opinion about the cause of a silicone embolism), review dismissed, 
950 So. 2d 414 (Fla. 2007); Demeniuk, 888 So. 2d at 657, 659 (finding Frye 
applicable to testimony of a causal connection between selective serotonin 
reuptake inhibitors and suicide/involuntary alcohol consumption where the 
opinions “were based on a novel scientific theory”); David v. Nat’l R.R. Passenger 
Corp., 801 So. 2d 223, 226 (Fla. 2d DCA 2001) (remanding for a determination of 
whether the theory that repetitive motion can cause carpal tunnel syndrome was 
generally accepted); Kaelbel Wholesale, Inc., 785 So. 2d at 548-50 (rejecting 
- 37 ­
 
 
 
testimony linking ciguatera poisoning to the development of Guillain-Barré 
Syndrome where the theory of causation was not generally accepted); Poulin v. 
Fleming, 782 So. 2d 452, 452 (Fla. 5th DCA 2001) (applying Frye to testimony 
that prenatal exposure to radiation caused schizencephaly). 
As I explain more fully below, we have approved, and have seemingly 
applied, this approach. See U.S. Sugar Corp. v. Henson, 787 So. 2d 3, 5 (Fla. 1st 
DCA 2000) (applying Frye to testimony that the cumulative effect of pesticide 
exposure caused phrenetic nerve mononeuropathy and finding both the general 
causation theory and specific causation methodology to be generally accepted), 
approved, 823 So. 2d at 109 (commending and approving “the thoughtful analysis 
performed by the district court below evaluating the general acceptance of the 
methodologies and scientific principles supporting Henson’s experts’ opinions”).   
Other courts recognize this proposition as well.  As a federal appellate court 
has said, 
The underlying predicates of any cause-and-effect medical testimony 
are that medical science understands the physiological process by 
which a particular disease or syndrome develops and knows what 
factors cause the process to occur.  Based on this predicate 
knowledge, it may then be possible to fasten legal liability for a 
person’s disease or injury. 
Black v. Food Lion, Inc., 171 F.3d 308, 314 (5th Cir. 1999); cf. McClain v. 
Metabolife Int’l Inc., 401 F.3d 1233, 1239 (11th Cir. 2005) (noting that in toxic 
tort cases where the medical community does not generally recognize an agent as 
- 38 ­
 
 
  
 
 
 
both toxic and capable of causing the injury alleged, “the Daubert analysis covers 
not only the expert’s methodology for the plaintiff-specific questions about 
individual causation but also the general question of whether the drug or chemical 
can cause the harm plaintiff alleges”). Permitting an expert to testify that X caused 
Y in a specific case without requiring the general acceptance of the theory that X 
can ever cause Y expands the “pure opinion” exception to the point where it 
swallows the rule. 
B. U.S. Sugar and Castillo 
Two of our recent decisions confirm the applicability of Frye to general 
causation testimony.  See U.S. Sugar Corp. v. Henson, 823 So. 2d 104 (Fla. 2002); 
Castillo v. E.I. Du Pont De Nemours & Co., 854 So. 2d 1264 (Fla. 2003). U.S. 
Sugar involved a Frye challenge to an expert’s opinion that the cumulative effect 
of pesticide exposure caused the claimant’s phrenetic nerve mononeuropathy.  823 
So. 2d at 106. The First District applied Frye to conclude: 
Because our de novo review establishes that there is general 
acceptance in the relevant scientific community both (i) for claimant’s 
general causation theory that certain pesticides to which he was 
repeatedly exposed over a long period of time can cause peripheral 
neuropathy, and (ii) for the differential diagnosis methodology 
employed by claimaint’s physicians, which they used to exclude other 
facts that might cause his condition and to determine that his pesticide 
exposure specifically caused his injury, we affirm. 
- 39 ­
 
 
 
 
 
 
 
 
 
 
U.S. Sugar Corp., 787 So. 2d at 5 (emphasis added).  On review, we agreed that it 
is “generally accepted in the scientific community that ‘organophosphates are 
neurotoxic’” and that “[b]ecause of this generally accepted scientific foundation, 
the ‘extrapolation’ method utilized by these experts in concluding that chronic 
exposure to these pesticides caused claimant’s condition is an acceptable scientific 
technique in this case.” U.S. Sugar, 823 So. 2d at 109 (quoting U.S. Sugar, 787 
So. 2d at 16-17). We went on to “highlight” (referring to the Third District’s 
decision in E.I. DuPont De Nemours & Co., Inc. v. Castillo, 748 So. 2d 1108 (Fla. 
3d DCA 2000), quashed, 854 So. 2d 1264 (Fla. 2003)) that “under Frye, the 
inquiry must focus only on the general acceptance of the scientific principles and 
methodologies upon which an expert relies in rendering his or her opinion.”  U.S. 
Sugar, 823 So. 2d at 110. 
The other case in which we confirmed Frye’s application to general 
causation was Castillo, 854 So. 2d at 1264.  That case involved expert testimony 
that fetal exposure to a fungicide (Benlate) caused a birth defect (microphthalmia).  
Id. at 1267. The Frye challenge related to the methodology for determining 
whether, and at what level, Benlate could cause birth defects in humans.  Id.  The 
defendants acknowledged that the in vivo tests (animal toxicology) and in vitro 
tests (analysis of the effects of suspected substances on isolated cell systems) 
underlying the opinion were generally accepted methods for analyzing toxicology, 
- 40 ­
 
 
 
 
 
 
 
 
but they argued that the expert’s extrapolation from the tests to conclude that 
Benlate is a human teratogen was not generally accepted.  Castillo, 748 So. 2d at 
1116, 1118. The district court found that the expert’s extrapolation from the tests 
was subject to and failed to satisfy Frye. Id. at 1120-21 (“[W]here, as here, 
plaintiffs wish to establish a substance’s teratogenicity in human beings based on 
animal and in vitro studies, the methodology used in the studies, including the 
method of extrapolating from the achieved results, must be generally accepted in 
the relevant scientific community.”).  On review, we disagreed, concluding that the 
expert conclusions reached through extrapolation fell outside of Frye 
consideration: 
By considering the extrapolation of the data from the 
admittedly acceptable experiments, the Third District went beyond the 
requirements of Frye, which assesses only the validity of the 
underlying science. Frye does not require the court to assess the 
application of the expert’s raw data in reaching his or her conclusion.  
We therefore conclude that the Third District erroneously assessed the 
Castillos’ expert testimony under Frye by considering not just the 
underlying science, but the application of the data generated from that 
science in reaching the expert’s ultimate conclusion. 
Castillo, 854 So. 2d at 1276 (emphasis added).   
U.S. Sugar and Castillo confirm that while expert opinions deduced from 
generally accepted principles are not subject to Frye, the underlying principles are. 
U.S. Sugar, 823 So. 2d 109-10 (“[W]hen the expert’s opinion is based on generally 
accepted scientific principles and methodology, it is not necessary that the expert’s 
- 41 ­
 
 
  
 
deductions based thereon and opinion also be generally accepted as well.”); 
Castillo, 854 So. 2d at 1269, 1276 (“We must consider whether the scientific 
principles upon which the Castillo’s experts based their opinions are generally 
accepted in the scientific community.”). 
The majority characterizes the challenge in this case as one to the “experts’ 
conclusions that trauma caused Marsh’s fibromyalgia.”  Majority op. at 11. But 
Respondents do not challenge the experts’ conclusions.  Rather, they challenge the 
premise behind them—the theory that trauma can ever cause fibromyalgia.  If it 
were generally accepted in the scientific community that trauma can cause 
fibromyalgia, then I would agree that the experts’ deduction from that principle to 
conclude that trauma caused Marsh’s fibromyalgia would not be subject to Frye. 
See Castillo, 854 So. 2d at 1276; U.S. Sugar, 823 So. 2d at 110. It is that 
underlying principle, however, that is contested here. 
I also disagree with the majority’s conclusion that Marsh’s experts’ 
testimony is not subject to Frye simply because the methodology used— 
differential diagnosis—is generally accepted.  Majority op. at 11.  Differential 
diagnosis is certainly a generally accepted methodology for determining specific 
causation. The use of differential diagnosis alone, however, does not exempt 
causation testimony from Frye. Differential diagnosis is merely a “scientific 
methodology in which the expert eliminates possible causes of a medical condition 
- 42 ­
 
 
 
to arrive at the conclusion as to the actual debilitating factor.”  U.S. Sugar, 823 So. 
2d at 106. It is a process of elimination—the patient’s condition, call it X, was not 
caused by A, B, or C; therefore, X must have been caused by D.  But before causes 
A, B, and C can be scientifically excluded as a specific cause (i.e., A did not cause 
X), they must first be scientifically included as a general cause (i.e., A can cause 
X). Experts cannot conclude, through a process of elimination, that trauma caused 
the plaintiff’s fibromyalgia without first demonstrating the reliability of the theory 
that trauma can cause it. 
To illustrate with an extreme example: a patient suffering from depression 
sees a doctor because her arm hurts.  She does not know why her arm hurts.  The 
doctor diagnoses a broken arm.  The patient cannot tell the doctor how she broke 
her arm.  The doctor may, through performing tests and interviewing the patient, 
conclude that it could not have been a car accident (the patient was not involved in 
an accident) and it could not have been playing sports (the patient does not play 
sports), but the doctor cannot then conclude that it must have been the depression 
that caused the broken arm—unless, of course, the doctor can show that the theory 
that depression can cause a broken arm is generally accepted in the scientific 
community.  Similarly, only if it is generally accepted that trauma is a potential 
cause of fibromyalgia may an expert testify that, through differential diagnosis, she 
has concluded that trauma caused this plaintiff’s fibromyalgia.  See, e.g., McClain, 
- 43 ­
 
 
 
 
 
401 F.3d at 1253 (“[A]n expert does not establish the reliability of his techniques 
or the validity of his conclusions simply by claiming that he performed a 
differential diagnosis on a patient.”); Clausen v. M/V New Carissa, 339 F.3d 1049, 
1057-58 (9th Cir. 2003) (“The first step in [a differential diagnosis] is to compile a 
comprehensive list of hypotheses . . . .  The issue at this point in the process is 
which of the competing causes are generally capable of causing the patient’s 
symptoms or mortality.  Expert testimony that rules in a potential cause that is not 
so capable is unreliable.”) (citation omitted); Food Lion, 171 F.3d at 314 
(recognizing that the causes of fibromyalgia are unknown and “[a]bsent these 
critical scientific predicates . . . no scientifically reliable conclusion on causation 
can be drawn” such that the “use of a general methodology cannot vindicate a 
conclusion for which there is no underlying medical support”); Maras v. Avis Rent 
A Car Sys., Inc., 393 F. Supp. 2d 801, 809 (D. Minn. 2005) (noting that the 
plaintiff failed to demonstrate a proper basis for “ruling in” an accident as the 
cause of fibromyalgia and thus, use of differential diagnosis did not render the 
testimony admissible).  Differential diagnosis is not a wild card that can be used to 
introduce novel scientific theories into the courtroom.  Any other logic would 
revert us to the science of the Salem Witch Trials.  See, e.g., Laurie Winn Carlson, 
A Fever in Salem xiv (1999) (“With the limited scientific and medical knowledge 
of the time, physicians who were consulted could only offer witchcraft as an 
- 44 ­
 
 
 
 
 
 
explanation.”); cf. Carl Sagan, The Demon-Haunted World 26 (1995) (“Science is 
an attempt, largely successful, to understand the world, to get a grip on things, to 
get hold of ourselves, to steer a safe course.  Microbiology and meteorology now 
explain what only a few centuries ago was considered sufficient cause to burn 
women to death.”).   
II. THE TESTIMONY FAILS TO SATISFY FRYE 
Having determined that testimony causally connecting trauma to 
fibromyalgia is subject to the Frye test, the next question I address is whether the 
evidence in this case satisfied the test.  I conclude that the answer is “no.”  Frye 
requires the proponent to show general acceptance by a “clear majority” of the 
members of the relevant scientific community.  See, e.g., Brim, 695 So. 2d at 272; 
Hadden, 690 So. 2d at 576 n.2. The majority here concludes that testimony 
causally linking trauma to fibromyalgia is admissible because some experts 
recognize an association between the two.  Majority op. at 13. I cannot agree that 
such evidence satisfies Frye. As explained below, a review of the materials 
presented to the trial court, district court, and this Court, as well as opinions from 
other jurisdictions, demonstrate an ongoing debate on the issue of whether trauma 
can cause fibromyalgia. See, e.g., Ramirez, 810 So. 2d at 844 (recognizing that a 
court may consider “expert testimony, scientific and legal publications, and 
judicial opinions” in determining whether a theory has been “‘sufficiently tested 
- 45 ­
 
 
and accepted by the relevant scientific community’”) (quoting Brim, 695 So. 2d at 
272). No clear majority has emerged—either way.  Therefore, Marsh, as the 
proponent of the evidence, has failed to meet her burden.   
The record in this case contains a large amount of material.  However, the 
parties focused on six documents—three “consensus reports”—Frederick Wolfe et 
al., The Fibromyalgia Syndrome: A Consensus Report on Fibromyalgia and 
Disability, 23 J. Rheumatology 534 (1996) [hereinafter Consensus Report]; 
Muhammad B. Yunus et al., Fibromyalgia Consensus Report:  Additional 
Comments, 3 J. Clinical Rheumatology 324 (1997) [hereinafter Additional 
Comments]; and Anil Kumar Jain et al., Fibromyalgia Syndrome: Canadian 
Clinical Working Case Definition, Diagnostic and Treatment Protocols—A 
Consensus Document, 11 J. Musculoskeletal Pain 3 (2003) [hereinafter 2003 
Consensus Document]—and three studies (Dan Buskila et al., Increased Rates of 
Fibromyalgia Following Cervical Spine Injury, 40 Arthritis & Rheumatism 446 
(1997) [hereinafter Buskila study]; A.W. Al-Allaf et al., A Case-Control Study 
Examining the Role of Physical Trauma in the Onset of Fibromyalgia Syndrome, 
41 Rheumatology 450 (2002) [hereinafter Al-Allaf study]; and Moshe Tishler et 
al., Neck Injury and Fibromyalgia—Are They Really Associated?, 33 J. 
Rheumatology 1183 (2006) [hereinafter Tishler study]).  I address these documents 
below, along with others. 
- 46 ­
 
 
 
 
 
 
                                          
 
 
The Consensus Report, supra, at 534, resulted from a 1994 conference of 
fibromyalgia experts.  It specifically addresses the connection between trauma and 
fibromyalgia: 
Evidence that trauma can cause FM, a potential (or It Can) causal 
proposition, comes from a few case series or case reports and is 
insufficient to establish causal relationships. That trauma might cause 
FM sometimes, a predictive (or It Will) causal proposition, can only 
be addressed by epidemiological studies that measure the risk of 
potential exposures on the development of FM.  Epidemiologic 
studies of trauma and FM needed to address potential or predictive 
causality are currently not available. . . . 
Overall, then, data from the literature are insufficient to indicate 
whether causal relationships exist between trauma and FM. The 
absence of evidence, however, does not mean that causality does not 
exist, rather that appropriate studies have not been performed. 
Id. at 534-35 (footnotes omitted) (emphasis added).  In response to the Consensus 
Report, another group published the Additional Comments, supra. The authors 
recognized that “[o]ur scientific understanding of FMS is still very limited.”  Id. at 
324. However, with regard to causality, they disagreed with the Consensus Report, 
stating, “[I]t seems more than 51% likely that trauma does play a causative role in 
some FMS patients.” Id. at 325.7 
Later, another group published the 2003 Consensus Document, supra, which 
was primarily a summary of previous research.  The 2003 Consensus Document 
7. The focus of this statement is on the causal probability rather than the 
general acceptance of the causal theory—the relevant inquiry under Frye. 
However, the point seems to be that these experts believe trauma can cause 
fibromyalgia. 
- 47 ­
 
 
 
 
  
recognizes that no known cause of fibromyalgia exists, but reviews numerous 
studies to conclude that “[t]here is strong consistency in documentation that 
physical trauma such as a fall or motor vehicle accident, particularly a whiplash or 
spinal injury, can trigger FMS in some patients.” Id. at 44. The authors recognize, 
however, that further research on “[t]he etiology of FMS including genetic 
components and prodomal events such as physical trauma” is needed.  Id. at 61. 
Although not a “consensus” report, another recent document surveys 
physician opinions about the association between trauma and fibromyalgia.  See 
Kevin P. White et al., Perspectives on Posttraumatic Fibromyalgia: A Random 
Survey of Canadian General Practitioners, Orthopedists, Physiatrists, and 
Rheumatologists, 27 J. Rheumatology 790, 794 (2000) [hereinafter White survey]. 
The authors randomly surveyed Canadian physicians to determine which factors 
were deemed most important in an individual with widespread pain following a 
motor vehicle trauma.  Id. at 791. They found that the physicians surveyed “were 
reluctant to ascribe primary responsibility for chronic widespread pain to the 
trauma itself.”  Id. at 794. 
If these documents demonstrate anything, it is the lack of consensus on the 
issue, and therefore the lack of general acceptance of the theory that trauma can 
cause fibromyalgia.  The very fact that competing “consensus reports” exist, with 
- 48 ­
 
 
 
                                          
 
 
 
experts on each side, demonstrates the lack of general acceptance by a “clear 
majority” of members of the community. 
As the majority notes, see majority op. at 13, some articles do suggest an 
association between trauma and fibromyalgia.  But most of them are case reports 
and anecdotal accounts.8  I recognize that to satisfy Frye epidemiological studies 
confirming a causal theory are not always required, see, e.g., Castillo, 854 So. 2d at 
1270; U.S. Sugar, 823 So. 2d at 110, but if a majority of experts agrees about 
anything, it is that (1) the cause of fibromyalgia is unknown,9 and (2) to determine 
the relationship between fibromyalgia and trauma, more studies are needed.10 
8. See, e.g., Samuel A. McLean et al., Fibromyalgia After Motor Vehicle 
Collision: Evidence and Implications, 6 Traffic Injury Prevention 97, 97, 99 (2005) 
(recognizing a “plethora” of case reports and anecdotal accounts of fibromyalgia in 
close temporal association with trauma, but only one case-controlled study—the 
Buskila study—directly examining the relationship); Yoram Shir et al., Whiplash 
and Fibromyalgia:  An Ever-Widening Gap, 33 J. of Rheumatology 1045, 1046 
(2006) (noting that the link with trauma has been mostly based on patient report 
and retrospective studies); John B. Winfield, Pain in Fibromyalgia, 25 Pain 
Management in the Rheumatic Diseases 55, 63 (1999) (“The argument in favor of 
a connection between trauma and fibromyalgia is based on the experience of 
certain clinicians that trauma and fibromyalgia are associated . . . .”).   
9. See, e.g., Dan Buskila & Lily Neumann, Musculoskeletal Injury as a 
Trigger for Fibromyalgia/Posttraumatic Fibromyalgia, 2 Current Rheumatology 
Reports 104, 104 (2000) (“[T]he etiology and pathophysiology of FM are still 
unclear.”); 2003 Consensus Document, supra, at 43-44 (recognizing that “[t]here is 
no known single initiating cause” of fibromyalgia); Roland Staud, Fibromyalgia 
Pain: Do We Know the Source?, 16 Current Opinion in Rheumatology 157, 157 
(2004) (“Fibromyalgia syndrome is a chronic pain syndrome of unknown 
etiology . . . .”); Tishler study, supra, at 1183 (“The etiology and pathophysiology 
of this disorder remain unclear . . . .”); Consensus Report, supra, at 536 (“The 
- 49 ­
 
 
  
                                                                                                                                        
 
 
The parties primarily rely on three such studies: (1) the Buskila study; (2) 
the Al-Allaf study; and (3) the Tishler study. All three of these studies conclude 
that more research is needed to determine whether trauma causes fibromyalgia. 
The authors of the Buskila study, supra at 446, which was published in 1997, 
studied the relationship between cervical spine injury and the development of 
fibromyalgia.  They recognized that to date the evidence that trauma can cause 
fibromyalgia had been “equivocal” and “from a few case series or case 
cause(s) of FM are incompletely understood.”).  The Petitioner likewise recognizes 
that “the precise etiology and exact pathological mechanisms are not fully 
understood.” 
10. See, e.g., Buskila & Neumann, supra, at 107 (“Future research needs to 
be directed to prospective longitudinal evaluation of patients who fall victim to 
motor vehicle or industrial accidents to determine the natural history of 
postaccident FM.”); 2003 Consensus Document, supra, at 61 (recognizing that 
further research is “obviously needed” on the “etiology of FMS,” including the link 
to trauma); McLean et al., supra, at 99, 101 (stating that further case-control 
studies are needed to “more firmly establish causation”); Shir et al., supra, at 1046 
(“The debate . . . is not completely settled for an association of a triggering event 
and the onset of FM, but requires further study in order to reach a final 
conclusion.”); Staud, supra, at 159 (“Further prospective studies, however, are 
needed to confirm this association and to identify whether trauma plays a causal 
role for FMS pain.”); George W. Waylonis & Robert H. Perkins, Post-Traumatic 
Fibromyalgia: A Long-Term Follow-Up, 73 Am. J. of Physical Med. & 
Rehabilitation 403, 403 (1994) (recognizing that “literature investigating post­
traumatic fibromyalgia is quite limited”); Kevin P. White et al., Trauma and 
Fibromyalgia:  Is There an Association and What Does It Mean?, 29 Seminars in 
Arthritis & Rheumatism 200, 201, 209 (2000) (stating “there is limited evidence 
either to support or refute an association between trauma and FM” and that further 
studies are needed); Consensus Report, supra, at 534 (“Epidemiologic studies of 
trauma and FM needed to address potential or predictive causality are currently not 
available.”). 
- 50 ­
 
 
 
 
 
reports . . . insufficient to establish causal relationships.”  Id.  (footnotes omitted).  
They studied two groups of Israeli patients who visited an occupational clinic: (1) 
those with neck injuries (102 patients); and (2) those with leg fractures (fifty-nine 
patients). Id. at 447. The researchers found that twenty-two of the patients with 
neck injuries, and only one of the patients with a leg fracture, developed 
fibromyalgia.  Id. at 449. The article concludes that “[t]he present data in the 
literature are insufficient to indicate whether causal relationships exist between 
trauma and FMS. Our study, however, suggests that soft tissue trauma to the neck 
can result in an increased incidence of FMS compared with other injuries.”  Id. at 
451. 
Despite this conclusion, a later article by two of the same authors states: 
Traumatic incidents have been suggested as a possible etiologic factor 
relating to the onset of FM. However, evidence that musculoskeletal 
injury or trauma can cause FM comes from a few case series or 
anecdotal case reports. Reviewing the current literature reveals that 
data are insufficient to indicate whether causal relationships exist 
between trauma and FM. 
Buskila & Neumann, supra, at 107 (emphasis added). 
Another study examining “whether physical trauma precipitates the onset of 
fibromyalgia” is the Al-Allaf study, supra, at 451, a retrospective study based on 
patient recall. The researchers found that 39% of the fibromyalgia patients 
reported a history of trauma, compared with 24% of the control subjects, 
- 51 ­
 
 
 
 
suggesting “that physical trauma was significantly associated with the onset of 
FMS.” Id.  at 452. However, they cautioned: 
Our own results are, of course, retrospective and may be 
influenced by recall bias, but if they are confirmed in a prospective 
study this would lead us to speculate on the mechanisms by which 
trauma might preciptitate FMS. 
. . . . 
In conclusion, our study suggests that physical trauma in the 6 
months before the onset of symptoms is significantly associated with 
the onset of FMS in patients attending a rheumatology out-patient 
clinic. Further prospective studies are needed to confirm this 
association and to determine whether trauma has a causal role or if 
there are more important factors in the development of FMS. 
Id. at 453 (emphasis added).   
Thus, both the Buskila study and Al-Allaf study suggest an association 
between trauma and fibromyalgia.  However, they also indicate that before a causal 
connection can be found, more research is needed.  It has been noted that a call for 
further research does not necessarily indicate uncertainty, and that the purpose of a 
study is not to fix a cause but to “assess the existence and strength or absence of an 
association between an agent and a disease.”  Berry v. CSX Transp., Inc., 709 So. 
2d 552, 567, 568 n.12 (Fla. 1st DCA 1998). In this case, however, despite finding 
an association between trauma and fibromyalgia, the authors specifically 
recognized that insufficient data existed to find a causal relationship.   
The majority nevertheless deems the studies finding a mere association 
between trauma and fibromyalgia sufficient to satisfy Frye. Majority op. at 13. 
- 52 ­
 
 
 
 
 
Yet a recent study, the Tishler study, supra, at 1183—a prospective study 
published in 2006—suggests the absence of even that.  The Tishler study involved 
153 car accident patients who had been discharged from the emergency room with 
a whiplash injury, and a control group of forty-eight car accident patients 
hospitalized because of severe trauma.  Id.  The researchers found: 
The issue of trauma and FM remains controversial. . . . Several 
studies in the past, most of them retrospective, have reported that up 
to 50% of patients with FM can recall an event, most often physical 
trauma, that immediately preceded their symptoms.  An extensive 
review of the literature failed to yield solid conclusions concerning 
this issue. The only prospective study that found a causative link 
between trauma and FM is by Buskila, et al.  In this study, which was 
not followed by others, the authors found that 21.6% of patients with 
neck injury developed FM shortly after a work accident.  These data 
are impressive since in their control group of patients with leg 
fractures, the rate of FM was much lower . . . . We could not confirm 
these earlier findings; after a mean followup of 14.5 months, only one 
out of 153 patients with whiplash injury developed FM. 
. . . . 
In conclusion, the results of our prospective study do not 
support earlier observations about a link between neck trauma and 
FM. 
Id. at 1184-85 (footnotes omitted) (emphasis added); see also, Shir et al., supra, at 
1046 (“We now have a single, but large and well designed prospective study with a 
surprising conclusion. . . . Tishler’s conclusion should be upheld.”).   
Let me be clear: I do not argue that these studies demonstrate that trauma 
does not cause fibromyalgia.  My point is that no clear majority exists either way. 
Instead, the scientific community is in the middle of an ongoing and intense 
- 53 ­
 
 
 
 
 
debate. See, e.g., Shir et al., supra, at 1045 (“Opinions regarding an association 
between trauma such as whiplash injury (WLI) and subsequent FM are emotionally 
charged and highly polarized.”); McLean et al., supra, at 97 (“The ability of 
physical trauma . . . to trigger the development of FM remains the subject of 
intense debate.”); White survey, supra, at 790 (“There may be no issue more 
contentious in FM than the causative role of trauma.”); Winfield, supra, at 62-63 
(recognizing that “[t]rauma as a ‘trigger’ or cause of fibromyalgia is an important 
and contentious issue in modern American society” and that “[d]ebate, which 
actually has raged for much of this century, continues”) (footnotes omitted).  The 
very existence of this debate precludes Marsh from satisfying the requirement that 
this novel scientific principle be generally accepted.  See, e.g., Castillo, 854 So. 2d 
at 1268 (“The proponent of the evidence bears the burden of establishing by a 
preponderance of the evidence the general acceptance of the underlying scientific 
principles and methodology.”). 
My conclusion is consistent with cases from other jurisdictions considering 
this precise issue under both Frye and Daubert (or a Daubert-type analysis). See, 
e.g., Vargas v. Lee, 317 F.3d 498, 502-03 (5th Cir. 2003) (applying Daubert and 
excluding testimony that a car accident caused fibromyalgia); Food Lion, 171 F.3d 
at 314 (applying Daubert and finding testimony linking a slip-and-fall to 
fibromyalgia inadmissible); Maras, 393 F. Supp. 2d at 808-10 (finding testimony 
- 54 ­
 
 
 
 
 
 
 
 
 
 
 
 
that motor vehicle accident caused fibromyalgia failed to meet the general 
acceptance factor, among other factors, of Daubert); Hultberg v. Wal-Mart Stores, 
Inc., No. CIV. A. 97-2858, 1999 WL 244030, at *1 (E.D. La. Apr. 22, 1999) 
(applying Daubert and excluding testimony that a slip-and-fall accident caused 
fibromyalgia); Schofield v. Laboscam, Inc., No. CIV. A. CV-00-197, 2002 WL 
1335867, at *3 (Me. Super. Ct. June 6, 2002) (granting motion in limine to exclude 
testimony that a vehicle accident caused fibromyalgia); Jones v. Conrad, No. 
CA2000-12-257, 2001 WL 1001083, at *3-4 (Ohio Ct. App. Sept. 4, 2001) 
(finding testimony linking work accident to fibromyalgia inadmissible and the 
theory that trauma can cause fibromyalgia not generally accepted); Grant v. 
Boccia, 137 P.3d 20, 24 (Wash. Ct. App. 2006) (citing with approval the district 
court’s decision in Marsh and holding inadmissible under Frye testimony linking a 
car accident to fibromyalgia where “[n]one of the authorities presented by either 
party has the effect of persuasively establishing acceptance in the relevant 
community as to the cause of fibromyalgia or the causal role of trauma in the 
development of fibromyalgia”), review denied, 154 P.3d 919 (Wash. 2007); cf. 
Washburn v. Merck & Co., 213 F.3d 627, 2000 WL 528649, at *2 (2d Cir. May 1, 
2000) (No. 99-9121) (affirming exclusion of testimony that vaccination caused 
fibromyalgia and other conditions under Daubert because it was based “on little 
more than temporal correlation” between the vaccination and onset of symptoms); 
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Allison v. McGhan Med. Corp., 184 F.3d 1300, 1321-22 (11th Cir. 1999) 
(affirming exclusion of testimony that breast implants caused fibromyalgia); 
Wynacht v. Beckman Instruments, Inc., 113 F. Supp. 2d 1205, 1209 (E.D. Tenn. 
2000) (finding testimony linking a chemical spill to fibromyalgia and other 
conditions inadmissible under Daubert); Gross v. King David Bistro, Inc., 83 F. 
Supp. 2d 597, 602 (D. Md. 2000) (granting motion in limine to preclude testimony 
under Daubert that shigella infection caused fibromyalgia); Bushore v. Dow 
Corning-Wright Corp., No. 92-344-CIV-T-26C, 1999 WL 1116920, at *1 (M.D. 
Fla. Nov. 15, 1999) (applying Daubert and excluding testimony that breast 
implants caused fibromyalgia); Minner v. Am. Mortgage & Guar. Co., 791 A.2d 
826, 855 (Del. Super. Ct. 2000) (excluding evidence that a “sick building” caused 
fibromyalgia because “there appears to be a consensus that there is no known cause 
of FM”). 
I recognize that a few courts applying Daubert have admitted testimony 
causally linking trauma to fibromyalgia.  See, e.g., Epp v. Lauby, 715 N.W.2d 501, 
509-11 (Neb. 2006) (recognizing a “professional controversy regarding the causal 
relationship between physical trauma and fibromyalgia” and that “there is not a 
sufficient scientific consensus to say that the theory is generally accepted,” but 
noting that general acceptance is not determinative under Daubert and finding 
admissible testimony causally linking plaintiff’s car accident to fibromyalgia); 
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Reichert v. Phipps, 84 P.3d 353, 364-65 (Wyo. 2004) (finding causation testimony 
admissible because differential diagnosis is an acceptable method of diagnosing 
fibromyalgia and because the proffered expert opinions “were given in the overall 
context of a professional controversy over the link between physical trauma and 
FM, in which some experts take the position that there is, indeed, a causal 
connection”); cf. Adler v. Bayer Corp., 61 P.3d 1068, 1085 (Utah 2002) (holding 
admissible testimony linking chemical fumes to fibromyalgia where it was based 
on differential diagnosis).  These are in the minority, however, and they apply a 
different test.  Other than the Second District’s recent decision in Johnson, 880 
So. 2d at 721, however, I have found only one case applying a Frye-type test to 
testimony linking trauma to fibromyalgia that has found the testimony admissible.  
See Byrum v. Superior Court of Los Angeles County, No. B153001, 2002 WL 
243565, at *2 (Cal. Ct. App. Feb. 20, 2002). Even that case seems to conflict with 
another case within the same appellate district.  See Pflum v. Sears, Roebuck & 
Co., No. B161862, 2004 WL 348783, at *2 (Cal. Ct. App. Feb. 25, 2004) 
(concluding the issue was not preserved, but addressing the merits and finding a 
lack of “a reasonable degree of medical certainty that trauma can exacerbate 
fibromyalgia”).  
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III. CONCLUSION 
For the reasons stated, I would hold that expert testimony causally linking 
trauma to fibromyalgia is subject to, and fails, the Frye test. Our precedent dictates 
that this underlying scientific principle of causation is subject to the Frye test. 
Whether trauma can ever cause fibromyalgia is a subject of much debate, and 
therefore the view that it can has not been generally accepted.  I cannot agree with 
the majority that the jury should be left to sort out contentious and complex 
disputes about medical causation where experts in the relevant scientific 
community have been unable to agree.  See Brim, 695 So. 2d at 272 (“[W]e have 
expressly held that the trial judge must treat new or novel scientific evidence as a 
matter of admissibility (for the judge) rather than a matter of weight (for the 
jury).”); Ramirez, 651 So. 2d at 1168 (recognizing that “[t]he trial judge has the 
sole responsibility to determine” “the general acceptance of both the underlying 
scientific principle and the testing procedures used to apply that principle to the 
facts at hand”). Contrary to our admonition in Stokes, 548 So. 2d at 193-94 (“[A] 
courtroom is not a laboratory . . . . If the scientific community considers a 
procedure or process unreliable for its own purposes, then the procedures must be 
considered less reliable for courtroom use.”), the majority decision turns the 
courtroom into a laboratory.  For these reasons, I respectfully dissent. 
WELLS and BELL, JJ., concur. 
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Application for Review of the Decision of the District Court of Appeal - Certified 
Direct Conflict of Decisions 
Fifth District - Case No. 5D03-188 
 
(Orange County) 
John T. Stemberger and Shannon L. Akins, Orlando, Florida, 
 
for Petitioner 
Joseph Currier Brock and Steven W. Igou of Igou and Smith, Orlando, Florida; 
Elizabeth C. Wheeler, Orlando, Florida and Jane H. Clark, Ocoee, Florida; and E. 
Peyton Hodges and Robert W. Mixson of Cameron, Hodges, Coleman, LaPointe 
and Wright, P.A., Orlando, Florida, 
 
for Respondents 
Philip M. Burlington of Burlington and Rockenbach, P.A., West Palm Beach, 
Florida, and Michael S. Finch, Stetson University College of Law, Gulfport, 
Florida, on behalf of Academy of Florida Trial Lawyers; and Tracy Raffles Gunn 
of Fowler, White, Boggs, and Banker, P.A., Tampa, Florida, on behalf of Florida 
Defense Lawyers Association, 
as Amicus Curiae 
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