Case: 12-14502   Date Filed: 09/11/2014   Page: 1 of 41


                                                               [PUBLISH]



             IN THE UNITED STATES COURT OF APPEALS

                     FOR THE ELEVENTH CIRCUIT
                       ________________________

                             No. 12-14502
                       ________________________

        D.C. Docket Nos. 1:09-md-02051-CMA; 9:09-cv-80625-CMA



MARIANNE CHAPMAN,
DANIEL CHAPMAN,


                                                         Plaintiffs - Appellants,


                                   versus


THE PROCTER & GAMBLE DISTRIBUTING, LLC,
THE PROCTER & GAMBLE MANUFACTURING CO.,


                                                       Defendants - Appellees.

                       ________________________

                Appeal from the United States District Court
                    for the Southern District of Florida
                      ________________________

                            (September 11, 2014)

Before PRYOR, JORDAN and FAY, Circuit Judges.
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FAY, Circuit Judge:

       Marianne and Daniel Chapman appeal summary judgment for The Proctor &

Gamble Distributing, LLC and The Proctor & Gamble Manufacturing Company

(collectively “P&G”) in their products liability case concerning Fixodent, a denture

adhesive. We affirm.


               I. FACTUAL AND PROCEDURAL BACKGROUND


       Marianne Chapman suffers from myelopathy, a neurological condition or

spinal-cord disorder that affects the upper and lower extremities. She developed a

number of neurological symptoms from April 2006 through January 2009. 1 The

Chapmans maintain Marianne Chapman’s symptoms were caused by zinc-induced,

copper-deficiency myelopathy (“CDM”) from her use of two to four 68-gram tubes

of Fixodent denture adhesive each week for eight years. P&G counters that the

testimony of the Chapmans’ experts should not be admitted, because their

methodologies are unreliable and do not substantiate the conclusion that Fixodent

caused Marianne Chapman’s CDM.




1
  These symptoms included loss of feeling in her hands and feet, a progressive gait ataxia that
caused her to trip when walking in the dark and subsequently confined her to bed, a burning pain
in her hands and feet requiring opiod management, blood dyscrasias with anemia and
neutropenia (low red and white blood-cell counts), and subacute bilateral asymmetric wrist and
finger drop in both hands, limiting her ability to extend her fingers and thumbs. In re Denture
Cream Prods. Liab. Litig., 

, 1348 (S.D. Fla. 2011).
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       While zinc is an essential element for human growth, it is not found

separately in nature but occurs in various compounds, such as zinc acetate and zinc

sulfate. In 1990, P&G reformulated Fixodent to include a calcium-zinc compound

to improve its adhesion. The calcium-zinc compound in Fixodent is less

bioavailable than other zinc compounds, like zinc acetate.2 A case report in 2008

hypothesized zinc in denture adhesives may lead to copper deficiency, which could

cause neurologic injury. S.P. Nations, et al., Denture Cream: An Unusual Source

of Excess Zinc, Leading to Hypocupremia and Neurologic Disease, 71 Neurology

639 (2008). Thereafter, various individuals filed lawsuits nationwide against

GlaxoSmithKline (“GSK”), manufacturer of Poligrip, and P&G, manufacturer of

Fixodent.


       The Chapmans originally filed their case in Florida state court on April 1,

2009, against P&G, which removed it to federal court in the Southern District of

Florida on diversity jurisdiction.3 On June 9, 2009, the United States Judicial

Panel on Multidistrict Litigation (“MDL”) transferred these similar cases against

2
  The zinc in Fixodent enters a user’s digestive tract, when food is chewed and swallowed. The
absorption of zinc occurs in the small intestine, where the Chapmans contend it blocks copper
assimilation into the body, resulting in CDM. Bioavailability refers to accessibility to metabolic
and physiological body processes, while dissociation references how a compound separates into
component parts under particular conditions.
3
  The Chapmans’ Amended Complaint, filed on November 9, 2009, contains seven causes of
action, including state-law claims: (1) strict products liability, (2) negligence, (3) intentional
misrepresentation, (4) breach of express warranty, (5) implied warranty, (6) violation of the
Florida Deceptive and Unfair Trade Practices Act, Florida Statutes §§ 501.201, et seq., and (7)
loss of consortium. This appeal concerns only the products liability claim.
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GSK and P&G to Judge Cecilia M. Altonaga in the Southern District of Florida for

coordinated pretrial proceedings. In re Denture Cream Prods. Liab. Litig., No. 09-

2051-MD-Altonaga. Following the conclusion of pretrial proceedings, the

individual MDL plaintiffs had the right to transfer their cases back to their

respective district courts. Because this case was the only one filed in the Southern

District of Florida, it provided the judge with jurisdiction to proceed to trial.


       The Chapmans sought to prove causation primarily through four expert

witnesses. 4 Dr. George J. Brewer, Dr. Joseph R. Landolph, and Dr. Ebbing

Lautenbach would have testified generally whether Fixodent could cause CDM.

Dr. Steven A. Greenberg would have testified Marianne Chapman’s myelopathy

specifically was caused by her use of Fixodent. P&G moved to exclude the

Chapmans’ expert testimony under Daubert v. Merrell Dow Pharmaceuticals, Inc.,

, 

(1993). Briefing, supplemental briefing, and a

hearing addressed the issues raised by P&G’s motions. On June 13, 2011, one

week before trial was to begin on June 20, 2011, the district judge issued a

comprehensive order granting P&G’s motions to exclude the Chapmans’ expert

testimony. In re Denture Cream Prods. Liab. Litig., 

(S.D.

Fla. 2011).


4
 P&G also sought to exclude the testimonies of three additional experts for the Chapmans: Dr.
Frederick Raffa, Dr. J. Anthony Von Fraunhofer, and Dr. Michael S. Wogalter.
                                               4
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A. First Appeal


      1. District Court


      At the previously scheduled calendar call on June 14, 2011, the parties

discussed with the judge the best route to this court to decide whether the judge’s

Daubert order was correct—interlocutory appeal or summary judgment. P&G

argued the other MDL cases should be “stayed pending the appeals,” because “it

would make no sense for the parties to be litigating anything in those cases while

the issues that are set forth squarely in the Court’s order yesterday are addressed by

the 11th Circuit.” Hr’g Tr., June 14, 2011, at 6:3-10. The judge commented it

would be “futile” and “a waste of everyone’s resources” to have full briefing on

summary judgment “just so [the parties] could get to the 11th Circuit on the

correctness of [her] decision on the Daubert motions.” 

Instead, the

judge suggested the parties “consent to an entry of judgment with the right to

appeal the adverse Daubert ruling.” 

      On June 16, 2011, the judge held a scheduling conference to discuss further

the proper way to get her Daubert decision before this court. The judge recognized

“the problem is how do you get [the Daubert order] to the Appellate Court

[because] you can’t . . . appeal . . . a Daubert ruling. You need a final order.”

Hr’g Tr., June 16, 2011, at 6:21-23. She suggested “the way to do it is to have me

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enter judgment against [the Chapmans] with the understanding of the parties that

you are reserving your right to appeal . . . my adverse ruling on Daubert, but you

need a final order.” 

Since both parties wanted the Daubert order

reviewed by this court, the judge ordered the parties to “present to [her] a proposed

order that contemplates” an appealable final judgment. 

      On June 23, 2011, the parties submitted a Joint Stipulation of Dismissal with

Prejudice, agreeing to “1) the entry of judgment against [the Chapmans] on all

claims alleged against [P&G]; and, 2) the entry of dismissal with prejudice on all

[the Chapmans’] claims alleged against [P&G].” Jt. Stip. of Dismissal at 1-2.

The joint stipulation provided “the parties recognize that this stipulation is in the

best interest of all parties and judicial economy” and expressly reserved the

Chapmans’ right to appeal to this court. 

In accordance with the joint

stipulation, the judge entered final judgment on June 24, 2011, and the Chapmans

timely appealed.


      2. Court of Appeals


      This court recognized “our jurisdiction ‘must be both (1) authorized by

statute and (2) within constitutional limits.’” Chapman v. Proctor & Gamble

Distrib., LLC, No. 11-13371 at 2 (11th Cir. Jan. 4, 2012) (per curiam) (quoting

OFS Fitel, LLC v. Epstein, Becker & Green, P.C., 

, 1355 (11th Cir.

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2008)). While the district judge’s order was final under 28 U.S.C. § 1291, “to be

within constitutional limits,” it had to be “‘adverse as to the final judgment’ . . . to

satisfy the Article III case or controversy requirement.” 

). We noted “three ‘distinct factual ingredients that are critical to

the adverseness issue.’” 

). Those factual

requirements are: (1) the appealed order was “‘case-dispositive because it

foreclosed plaintiff from presenting the expert testimony required to prove [the

cause of action], which was a core element in all of its claims,’” (2) “plaintiff’s

attorney ‘candidly informed the district court of the impact of its sanctions ruling

on the plaintiff’s case,’” and (3) “‘importantly, the district court . . . agreed with

plaintiff’s counsel’s suggestion that the [appealed] ruling was case-dispositive.’”

(quoting OFS 

, 1358).


      We concluded the Chapmans did not meet the second and third OFS Fitel

requirements. Although the parties had informed the district judge her Daubert

order might be dispositive, the Chapmans “also argued that they could still muster

enough evidence to prove causation at trial even without the expert testimony,

specifically by presenting testimony from treating doctors.” 

Not only did

the Chapmans fail “‘candidly’” to inform the judge of the consequence of the

Daubert order, but also they “disputed that it was dispositive.” 

). Regarding the third requirement, we determined the

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district judge’s dismissal was not case-dispositive. It was unclear whether the

interlocutory appeal from the Daubert order excluding the Chapmans’ expert

witnesses was “the only basis for dismissal, or if the Chapmans could otherwise

have proceeded to trial and proved causation despite the exclusion, as they initially

conte[nd]ed.” 

In addition, the Chapmans’ representation that it was

undisputed that the Daubert order was case-dispositive was belied by their

persistently “claiming that the order was not case-dispositive.” 

Accordingly, we dismissed the appeal of the Daubert order for lack of standing,

because the Chapmans were not adverse to the final judgment. 

Appeal


      Following dismissal of the Chapmans’ first appeal by this court, the district

judge granted their motion to vacate the stipulated final judgment under Federal

Rule of Civil Procedure 60(b). P&G then moved for summary judgment, which

the Chapmans opposed, and P&G replied. Because the district judge had

determined none of the Chapmans’ proffered experts qualified as experts under

Daubert, P&G maintained the Chapmans could not use treating physicians as

experts at trial. Since these doctors had never been designated as experts, the

judge determined they were not qualified to testify regarding general or specific

causation of Marianne Chapman’s CDM. Accordingly, she granted P&G’s


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summary judgment motion and entered final judgment. The Chapmans appealed,

which is the case we now decide. We necessarily first must address the merits of

the district judge’s Daubert order, because it is incorporated by reference in the

Chapmans’ opposition to P&G’s summary judgment motion,5 and the parties’ first

appeal to this court was dismissed for lack of jurisdiction without addressing the

merits of the Daubert order.


                                    II. DISCUSSION


A. Daubert Analysis


       1. Distinguishing Daubert-Applicable Cases


       For analyzing cases involving alleged toxic substances, we have delineated

two categories. McClain v. Metabolife Int’l, Inc., 

, 1239 (11th Cir.

2005). The first category consists of “cases in which the medical community

generally recognizes the toxicity of the [substance] at issue” to “caus[e] the injury

plaintiff alleges.” Id.; Hendrix ex rel. G.P. v. Evenflo Co., 

, 1196

(11th Cir. 2010). In this category are “toxins like asbestos, which causes

asbestosis and mesothelioma; silica, which causes silicosis; and cigarette smoke,

5
 In their opposition to P&G’s summary judgment motion, the Chapmans stated: “Plaintiffs
explicitly reserve their right to appeal this Court’s June 13, 2011 decision and preserve all
arguments previously set forth in opposition to Defendants’ Daubert motions. All such
arguments are hereby incorporated herein by reference.” Chapmans’ Opp’n to P&G’s Summ. J.
Mot. at 7 n.11.
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which causes cancer.” 

. For judicial economy, federal

courts need not consider expert opinions for diagnoses “medical doctors routinely

and widely recognize as true, like cigarette smoking causes lung cancer and heart

disease, too much alcohol causes cirrhosis of the liver, and . . . the ingestion of

sufficient amounts of arsenic causes death.” 

n.5. In cases where the

cause and effect or resulting diagnosis has been proved and accepted by the

medical community, federal judges “need not undertake an extensive Daubert

analysis on the general toxicity question.” 6 

.


       In contrast, the second category contains cases, where the medical

community generally does not recognize the substance in question as being toxic

and having caused plaintiff’s alleged injury. 

require a two-part

Daubert analysis, comprised of (1) general causation, “whether the [substance] can

cause the harm plaintiff alleges,” 

specific causation, whether experts’

methodology determines the substance “caused the plaintiff’s specific injury,”

(citing 

). For cases in

category two, a district judge “must assess the reliability of the expert’s opinion on

general, as well as specific, causation.” 

added). The two

categories economize the time of a trial judge, who “does not need to waste time

6
 The focus for cases in the first category is “individual causation to plaintiff”—“was plaintiff
exposed to the toxin, was plaintiff exposed to enough of the toxin to cause the alleged injury, and
did the toxin in fact cause the injury?” 

.
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with a Daubert hearing ‘where the reliability of an expert’s methods is properly

taken for granted, and to require appropriate proceedings in the less usual or more

complex cases where cause for questioning the expert’s reliability arises,’”

n.5 (quoting Kumho Tire Co. v. Carmichael, 

, 152, 

, 1176 (1999)).


       The Chapmans represent the district judge should have analyzed this case

under McClain category one, because there is a general consensus in the medical

community that ingestion of zinc causes CDM. They cite medical textbooks and

journals as well as their experts 7 and those of P&G, who have recognized an

association between excess zinc and copper deficiency. See Rider v. Sandoz

Pharm. Corp., 

, 1199 (11th Cir. 2002) (“[W]hile they may support

other proof of causation, case reports alone ordinarily cannot prove causation.”).

But they fail to show that the zinc compound in Fixodent is in McClain category

one of medically accepted, cause-and-effect toxins, such as asbestos causing

asbestosis and cigarette smoking causing lung cancer and heart disease. 

7
  For example, the Chapmans quote from the report of their only expert unchallenged by P&G in
the Daubert proceedings, Dr. Joseph Prohaska, that “it is well understood in the scientific
community that excess zinc can result in low plasma copper.” Appellants’ Br. at 31 n.8 (citation,
internal quotation marks, and alteration omitted). The Chapmans, however, did not advance Dr.
Prohaska with their other seven proffered experts they argued could establish general and
specific causation, all of whom the district judge disqualified in her Daubert order. Moreover,
Dr. Prohaska was limited by his report to opining on “the hematological changes associated with
copper deficiency as well as the impact of zinc on copper status.” Prohaska Report at 2.


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& n.5. P&G notes: “Millions of consumers have regularly used Fixodent for

decades without complaint. Nevertheless, [the Chapmans] claim that Fixodent is

toxic because it contains zinc in a calcium-zinc compound—even though zinc is

undeniably an essential nutrient the body must have to function properly.”

Appellees’ Br. at 1; see Guinn v. AstraZeneca Pharm. LP, 

, 1257

(11th Cir. 2010) (per curiam) (recognizing in a products liability case that two-

thirds of patients who took an antipsychotic prescription drug, Seroquel, did not

experience weight gain, which plaintiff alleged was the cause of her diabetes).

Therefore, the district judge properly determined that Fixodent, containing zinc,

was in McClain category two and conducted the requisite Daubert review of

proffered expert testimony, which included a thorough hearing and consideration

of “thousands of pages of filings by the parties, including the experts’ reports and

depositions, and scientific literature.” In re Denture Cream Prods. Liab. 

.


      2. Daubert Review for Reliability of Expert Testimony


      Under Federal Rule of Evidence 702, expert testimony is admissible if (1)

the expert is qualified to testify regarding the subject of the testimony; (2) the

expert’s methodology is “sufficiently reliable as determined by the sort of inquiry

mandated in Daubert”; and (3) the expert’s testimony will assist the trier of fact in


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understanding the evidence or determining a fact at issue. United States v. Frazier,

, 1260 (11th Cir. 2004) (en banc) (citation and internal quotation

marks omitted). In considering the proffered expert testimony, a trial judge is

mindful “[t]he burden of establishing qualification, reliability, and helpfulness rests

on the proponent of the expert opinion.” 

the reliability and

relevance of proffered expert testimony, the judge performs a “gatekeeping”

function. 

n.7; see Quiet Tech.

DC-8, Inc. v. Hurel-Dubois UK Ltd., 

, 1342 (11th Cir. 2003)

(recognizing “one may be considered an expert but still offer unreliable

testimony”). We review a district judge’s exclusion of expert testimony only for

abuse of discretion. Gen. Elec. Co. v. Joiner, 

, 141-43, 

, 517 (1997). This “considerable leeway” accorded to the district judge,

Kumho Tire 

, 119 S. Ct. at 1176, requires us to defer to the

judge’s decision on expert testimony, “unless it is manifestly erroneous.” Rink v.

Cheminova, Inc., 

, 1291 (11th Cir. 2005) (citation and internal

quotation marks omitted). This deferential abuse-of-discretion standard is applied

stringently, even if a decision on expert testimony is “outcome determinative.” 8


8
  We have “explain[ed] why it is difficult to persuade a court of appeals to reverse a district
court’s judgment on Daubert grounds[,] . . . where the abuse of discretion standard thrives.”
United States v. Brown, 

, 1264, 1266 (11th Cir. 2005). “[A] district court is more
familiar with the procedural and factual details and is in a better position to decide Daubert
issues,” which “are not precisely calibrated and must be applied in case-specific evidentiary
circumstances that often defy generalization.” 

In “applying [the] abuse of discretion
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Gen. Elec. 

, 118 S. Ct. at 517; United States v. Brown, 

, 1266 (11th Cir. 2005).


        The Daubert Court identified four factors to guide district judges in

assessing the reliability of an individual expert’s methodology:


       (1) whether the expert’s methodology has been tested or is capable of
       being tested; (2) whether the theory or technique used by the expert
       has been subjected to peer review and publication; (3) whether there is
       a known or potential error rate of the methodology; and (4) whether
       the technique has been generally accepted in the relevant scientific
       community.

United Fire & Cas. Co. v. Whirlpool Corp., 

, 1341 (11th Cir. 2013)

(per curiam) (citing 

, 113 S. Ct. at 2796-97). These

factors are not “a definitive checklist or test,” 

, 113 S. Ct.

at 2796, and Daubert considerations are “applied in case-specific evidentiary

circumstances,” 

. “[T]he trial judge must have

considerable leeway in deciding in a particular case how to go about determining

whether particular expert testimony is reliable.” Kumho Tire 

,

119 S. Ct. at 1176.



standard, we must affirm unless we at least determine that the district court has made a clear
error of judgment, or has applied an incorrect legal standard.” 

(alteration in original) (citation and internal quotation marks omitted). Clearly, the abuse-of-
discretion standard applied in Daubert cases is specialized and specifically addresses the narrow
issue of the admission of reliable expert trial testimony rather than the general abuse-of-
discretion standard implicated in other civil and criminal cases, which makes them not
comparable.
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      While the inquiry is “a flexible one,” the focus “must be solely on principles

and methodology, not on the conclusions that they generate.” 

, 113 S. Ct. at 2797 (emphasis added); see McDowell v. Brown, 

, 1298 (11th Cir. 2004) (recognizing a trial judge “should meticulously focus

on the expert’s principles and methodology, and not on the conclusions that they

generate”). “But conclusions and methodology are not entirely distinct from one

another”; neither Daubert nor Federal Rule of Evidence 702 requires a trial judge

“to admit opinion evidence that is connected to existing data only by the ipse dixit

of the expert.” Gen. Elec. 

, 118 S. Ct. at 519. Instead, the

judge “is free to ‘conclude that there is simply too great an analytical gap between

the data and the opinion proffered.’” 

(quoting Gen.

Elec. 

, 118 S. Ct. at 519); see 

(noting “there is no fit where a large analytical leap must be made between the

facts and the opinion,” such as proffering animal studies concerning a type of

cancer in mice to establish a different cancer in humans (citing Gen. Elec. 

, 118 S. Ct. at 519)). The district judge has “the task of ensuring that an

expert’s testimony both rests on a reliable foundation and is relevant to the task at

hand.” 

, 113 S. Ct. at 2799.


      As gatekeeper for the expert evidence presented to the jury, the judge “must

do a preliminary assessment of whether the reasoning or methodology underlying

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the testimony is scientifically valid and of whether that reasoning or methodology

properly can be applied to the facts in issue.” Kilpatrick v. Breg, Inc., 

, 1335 (11th Cir. 2010) (citation and internal quotation marks omitted). It is

“proper” and “necessary” for the trial judge “to focus on the reliability” of a

proffered expert’s “sources and methods.” 

Under Daubert, the

“district judge asked to admit scientific evidence must determine whether the

evidence is genuinely scientific, as distinct from being unscientific speculation

offered by a genuine scientist.” Allison v. McGhan Med. Corp., 

,

1316-17 (11th Cir. 1999) (citation and internal quotation marks omitted).


      a. General Causation


      General causation refers to the “general issue of whether a substance has the

potential to cause the plaintiff’s injury.” 

n.1. The district

judge consolidated her consideration of the proffered testimonies of Dr. Brewer,

Dr. Landolph, and Dr. Lautenbach regarding general causation. Neither the judge

nor the parties questioned that these three experts were qualified to testify based on

their credentials, the first part of the Rule 702 test for admission of expert

testimony. 

. The judge, however, determined that their

methodologies were not sufficiently reliable to satisfy part two of the test and

therefore would not assist the trier of fact in understanding the evidence, part three


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of the test. 

review the judge’s analysis that caused her to reach that

conclusion.


      At the outset, the judge placed this case in McClain category two, where

“the medical community does not generally recognize the agent as both toxic and

causing the injury plaintiff alleges.” 

. To establish

generally “Fixodent is capable of causing a myelopathy,” the Chapmans proffered

the testimonies of three experts. In re Denture Cream Prods. Liab. Litig., 795 F.

Supp. 2d at 1350. “Dr. Brewer would testify ‘that zinc containing Fixodent

denture adhesives are a health hazard and capable of causing severe hematological

and neurological injury.’” 

(quoting Brewer Report). “Dr. Landolph

would testify ‘that long-term use of Fixodent (containing 1.69% zinc) will result in

. . . neurotoxic, neurologic, and hematologic consequences.’” 

(quoting

Landolph Report). Dr. Lautenbach would testify “that there is ‘an association

between Fixodent and myeloneuropathy’ and he would ‘consider the

myeloneuropathy as a “probable” reaction related to denture adhesive use.’” 

Report).


      The judge reviewed reliable methodologies, including dose-response

relationship, epidemiological evidence, background risk of the disease,

physiological processes involved, and clinical studies. 

-57. The judge


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determined the Chapmans’ experts did not satisfy any of these recognized

methodologies. Failure to satisfy any of the four reliability factors recognized in

Daubert is sufficient to preclude the testimony of any of the general causation

experts from testifying at trial. 509 U.S. at 

.

Recognizing all substances potentially can be toxic, the judge noted “‘the

relationship between dose and effect (dose-response relationship) is the hallmark

of basic toxicology,’” and “‘is the single most important factor to consider in

evaluating whether an alleged exposure caused a specific adverse effect.’” 9 In re

Denture Cream Prods. Liab. 

(quoting 

). The judge noted, however, neither the Chapmans’ general-

9
  The judge quoted the deposition testimonies of the three general-causation experts to show their
inability to state the Fixodent dosage to put an individual at risk of developing myelopathy:

       Dr. Brewer:

       Q. Have you ever determined the dose of Fixodent necessary to consistently place
       individuals into a negative copper balance?
       A. Experimentally, no.
              ....
       Dr. Lautenbach:

       Q. Now, do you know how much below normal . . . serum copper has to be and
       for how long before you have myelopathies?
       A. I don’t know.

       Dr. Landolph:

       Q. So no studies have been done to determine how low the copper must be in the
       serum and for how long to cause myelopathy?
       A. I had not seen such a precise curve . . . .

In re Denture Cream Prods. Liab. 

n.16 (deposition citations
omitted).
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causation experts “nor the articles on which they rely determine how much

Fixodent must be used for how long to increase the risk of a copper-deficiency, or

for how long a copper-deficiency must persist before an individual is at an

increased risk of developing a myelopathy.” 

Similarly, the judge

recognized “[e]pidemiology is the ‘best evidence of causation’” in cases involving

toxic substances. 

(quoting 

n.8). But she

determined the Chapmans’ “experts have no analytical epidemiological evidence

on which to base their inference of causation.” 10 

further noted “[b]ackground risk of disease ‘is the risk a plaintiff

and other members of the general public have of suffering the disease or injury that

plaintiff alleges without exposure to the drug or chemical in question.’” 

(quoting 

). While “‘[a] reliable methodology should

take into account the background risk,’” the judge found the Chapmans’ “causation

experts uniformly testified that they did not know the background risk of copper-



10
   The judge supported the lack of epidemiological evidence with Dr. Lautenbach’s deposition
testimony:

       Q. To the best of your knowledge, there are no controlled population-based
       epidemiologic studies testing whether there is an association between denture
       adhesive and the development of hematologic or neurologic disease. Correct?
       A. That’s correct.

In re Denture Cream Prods. Liab. 

n.21 (deposition citation
omitted).
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deficiency myelopathy,” which was “a serious methodological deficiency.” 11 

original) (quoting 

). The judge explained:


       [T]he question of background risk is important because it could be
       coincidence that any particular denture-cream user has a myelopathy
       or copper-deficiency myelopathy. Some people use denture cream
       and some people have a myelopathy; it is possible (and depending on
       the incidence of myelopathies, likely) that some denture-cream users
       have an idiopathic myelopathy simply due to the background
       distribution of that disease. Without a baseline, any incidence may be
       coincidence.




11
 The Chapmans’ general-causation experts testified concerning the lack of background risk of
CDM at their respective depositions:

       Dr. Brewer:

       Q. Do you know the incidence of myeloneuropathies in the United States?
       A. No.
       Q. Do you know the incidence of myeloneuropathies, myelopathies, or
       myeloneuropathies [sic] amount uses of zinc-containing denture adhesives in the
       United States?
       A. No.

       Dr. Lautenbach:

       Q. Do you know what the incidence of myelopathy is in the general population?
       A. I don’t. I’m not sure it’s been well defined.

       Dr. Landolph:

       Q. You are unable to give me a number setting forth the incidence of
       myeloneuropathy among users of zinc containing denture adhesives in the United
       [S]tates, correct?
       A. That’s correct, the precise number, I don’t have that data.

In re Denture Cream Prods. Liab. 

n.22 (first alteration in
original) (deposition citations omitted).


                                                20
             Case: 12-14502    Date Filed: 09/11/2014   Page: 21 of 41

The judge concluded the absence of background risk of disease was “a

substantial weakness” in the Chapmans’ experts’ general-causation reasoning. 

deposition admissions of Dr. Brewer, Dr. Lautenbach, and Dr.

Landolph regarding their lack of knowledge of dose-response, epidemiological

evidence, and background risk of disease, methodologies this circuit has

recognized as indispensable to proving the effect of an ingested substance, we

conclude that the testimonies of these proffered experts could not establish general

causation of myelopathy by Fixodent. Because these experts have failed to

demonstrate the primary methods for proving the zinc in Fixodent causes

myelopathy, their secondary methodologies, including plausible explanations,

generalized case reports, hypotheses, and animal studies are insufficient proof of

general causation. This latter evidence could mislead the jury by causing it to

consider testimony that was insufficient by recognized primary methodologies to

prove using Fixodent causes myelopathy. As gatekeeper for the evidence

presented to the jury, the judge did not abuse her discretion or commit manifest

injustice by precluding the testimonies of Dr. Brewer, Dr. Lautenbach, and Dr.

Landolph as experts on general causation.


      b. Specific Causation




                                         21
             Case: 12-14502      Date Filed: 09/11/2014   Page: 22 of 41


      “Specific causation refers to the issue of whether the plaintiff has

demonstrated that the substance actually caused injury in her particular case.”

n.1. The Chapmans proffered only one expert to prove

specific causation, Dr. Greenberg, who would testify at trial: “‘[A] diagnosis of

copper deficiency myelopathy is certain . . . [and] in this patient, it was precisely

the ingested zinc in the denture cream that caused her copper deficiency.’” In re

Denture Cream Prods. Liab. 

(alterations and

ellipsis in original) (quoting Greenberg Report). His conclusion allegedly resulted

from “the scientifically accepted methodology of differential diagnosis,” 

, “a medical process of elimination whereby the possible causes of

a condition are considered and ruled out one-by-one, leaving only one cause

remaining,” 

. Differential diagnosis includes three steps:

(1) the patient’s condition is diagnosed, (2) all potential causes of the ailment are

considered, and (3) differential etiology is determined by systematically

eliminating the possible causes. 

. A reliable differential

analysis “need not rule out all possible alternative causes,” but “it must at least

consider other factors that could have been the sole cause of the plaintiff’s injury.”

. Differential diagnosis, “however, will not usually

overcome the fundamental failure of laying a scientific groundwork for the general




                                          22
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toxicity of the drug and that it can cause the harm a plaintiff suffered.” 

.


       While differential diagnosis as a scientifically accepted methodology meets

the Daubert guiding factors for district judges in deciding reliability, 509 U.S. at

, Dr. Greenberg did not follow it. Marianne

Chapman’s treating physicians had not diagnosed her with CDM or informed her

that her Fixodent use caused her neurologic symptoms. 12 Although her diagnosis

generally was “neurological syndrome,” she was not professionally diagnosed with

CDM until Dr. Greenberg examined her in the course of this litigation as the

Chapmans’ specific-causation expert.13 Greenberg Report at 10.



12
   Marianne Chapman’s medical history reveals she had experienced neurologic ailments in her
childhood, long before her Fixodent use began in 2001. Matthew E. Fink (P&G expert) Report
at 4-5. As a child, she had suffered frequent migraine headaches and was treated for unexplained
foot and ankle pain. 

She was evaluated during her teen years for pain from her shoulder
through her leg. 

series of recurrent falls, some of which resulted in hospitalization,
she complained of pain in her lower extremities, numbness, and decreased sensation. 

In
adulthood, before her use of Fixodent, Marianne Chapman was diagnosed with hereditary
hemorrhagic telangiectasia, a genetic disorder often accompanied with spinal cord, neurologic
ailments. Marianne Chapman Dep. at 39:20-25; Fink Report at 16.
13
   Marianne Chapman’s husband first “diagnosed” her medical ailments as the result of her
ingestion of zinc by researching the issue on the Internet. See Daniel Chapman Dep. at 57:15-24
(“A. I looked up her symptoms and I learned about zinc poisoning. Q. Now, prior to the time
when you did that, had anybody suggested to you that it could be zinc poisoning? A. No. Q. So
are you the first person that thought Marianne Chapman, your wife, might have zinc poisoning?
A. Yes.”); Marianne Chapman Dep. at 111:13-25 (“When did it first come to your attention that
there might be some nerve problems that could result from the zinc in Fixodent or other dental
adhesives? . . . A. In the beginning of ’09 when my husband was looking up neuropathy, the
browser log popped up with all different types of neuropathy, links to neuropathy and possible
causes of neuropathy. And that’s when he had brought it to my attention that the zinc in the
denture cream could cause neuropathy.”); Greenberg Report at 6 (noting Marianne Chapman and
                                               23
              Case: 12-14502      Date Filed: 09/11/2014      Page: 24 of 41


       Marianne Chapman’s medical history included neurological ailments that

occurred before and after her Fixodent use.14 Notably, her neurological symptoms

continued after she ceased using Fixodent. 15 “Temporal proximity is generally not

a reliable indicator of a causal relationship.” 

. “The

temporal connection between exposure to chemicals and an onset of symptoms,

standing alone, is entitled to little weight in determining causation.” 

(citation, internal quotation marks, and alteration omitted). But Dr.

Greenberg failed to explore fully other potential causes of Marianne Chapman’s

CDM, which he diagnosed in the course of this litigation. In re Denture Cream

Prods. Liab. 

. In addition to copper deficiency as

the cause of Marianne Chapman’s neurological ailments, Dr. Greenberg had

identified “structural spinal cord injury, multiple sclerosis, and vitamin B12



her husband “became concerned about the possibility of zinc poisoning after research on the
Internet”).
14
   After Marianne Chapman began using Fixodent, she again complained of pain in her lower
extremities. Marianne Chapman Dep. 12:25-13:14. She was diagnosed with and treated for
vitamin B12 deficiency, which has been associated with myelopathy. Fink Report at 14;
Greenberg Dep. 75:1-9. Following brief improvement, her neurologic ailments returned in 2006,
when she experienced burning and numbness in her legs, poor balance, and the eventual loss of
motor control in her right hand. Fink Report at 14-15. In 2006, Marianne Chapman also
developed anemia (low red blood cells) and neutropenia (low white blood cells). Greenberg
Report at 5 (Table 3). She had normal red and white blood-cell measurements in May and
November 2006, while she continued to use Fixodent; her neutropenia normalized permanently
in September 2008, before she stopped using Fixodent in 2009. Id.; Fink Report at 15.
15
   Ten months after Marianne Chapman stopped using Fixodent, she reported worsening hand
weakness and wrist drop. Fink Report at 15. Two years after she ceased using Fixodent, in
2011, she had a recurrence of a neurological problem, a positive Romberg sign of unsteady
balance with her eyes closed, which was not present in 2010. Greenberg Report at 7; Fink
Report at 13.
                                             24
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deficiency.” 16 

extensive medical history of neurological problems

since childhood, it is entirely possible that Marianne Chapman had the myelopathy

condition that she attributes to Fixodent prior to her use of the denture cream,

because her symptoms occurred before and after using Fixodent. See 

(“Because [plaintiff] was diagnosed with diabetes only four years

after beginning to take Seroquel, the temporal relationship in this case does not

provide strong evidence of causation; in fact, it appears to equally indicate that

[plaintiff] may have already developed diabetes before ever taking Seroquel.”

(emphasis added)). In addition, Dr. Greenberg recognized lymphoproliferative

disorders as possible causes of Marianne Chapman’s hematological syndrome and

“malabsorption and gastric bypass surgery as potential causes for her copper-

deficiency.” In re Denture Cream Prods. Liab. 

(emphasis added).


       A reliable differential analysis requires an expert to “compile a

comprehensive list of hypotheses that might explain” a plaintiff’s condition.
16
   P&G contended to the district judge that Dr. Greenberg also should have considered other
hereditary and acquired diseases that could have caused Marianne Chapman’s myelopathy,
including adrenomyeloneuropathy, complicated hereditary spastic paraplegia, Charcot-Marie-
Tooth disease, hereditary motor and sensory neuropathy Type V, subtypes of spinocerebeller
atrophy, hereditary ataxia with neuropathy, vitamin E deficiency, Sjogren’s syndrome,
sarcoidosis, HTLV-1, neuromylitis optica, and multiple-vitamin-deficiency syndrome. In re
Denture Cream Prods. Liab. 

. The judge noted P&G’s argument
concerning hereditary neuropathies, including myelopathies, “are far more common than copper-
deficiency myelopathies,” making Marianne Chapman’s myelopathy “more likely caused by a
genetic condition than by Fixodent, especially considering her personal medical history.” 

(citation and internal quotation marks omitted).
                                             25
             Case: 12-14502     Date Filed: 09/11/2014    Page: 26 of 41

(citation and internal quotation marks omitted). The

“expert must provide reasons for rejecting alternative hypotheses using scientific

methods and procedures and the elimination of those hypotheses must be founded

on more than subjective beliefs or unsupported speculation.” 

(citation

and internal quotation marks omitted). An expert’s failure to enumerate a

comprehensive list of alternative causes and to eliminate those potential causes

determines the admissibility of proposed specific-causation testimony. See 

(determining no abuse of discretion in concluding the specific-

causation expert’s hypothesis was unreliable under Daubert, because of failure to

consider possible alternative causes of plaintiff’s diabetes).


      Significantly, after concluding his report on Marianne Chapman, Dr.

Greenberg performed an additional, reasonable test on her to determine if she had

arterial venous malformation in her thoracic spinal cord. The judge found Dr.

Greenberg’s “failure to perform a test he considered reasonable before opining on

the cause of Ms. Chapman’s disease shows a lack of methodological rigor in

reaching the diagnosis in his report,” because he “did not consider the possibility

of an idiopathic cause for Ms. Chapman’s myelopathy.” In re Denture Cream

Prods. Liab. 

. Dr. Greenberg failed to consider

obvious alternative causes for Marianne Chapman’s CDM, such as hereditary and

acquired conditions known to cause myelopathies. See 

                                          26
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(affirming exclusion of plaintiff’s expert witness following Daubert proceedings,

when the expert’s testimony revealed facts casting “substantial doubt on whether

Seroquel contributed to [plaintiff’s] development of diabetes,” since plaintiff “had

multiple risk factors that could have been the sole cause of [her] diabetes[,] and

[the expert] was unable to determine the relative risk of each factor”). Instead, Dr.

Greenberg pursued his view that zinc-associated copper deficiency was responsible

for Marianne Chapman’s neurological and hematological symptoms. Yet, he

provided no support for his hypothesis that Marianne Chapman’s anemia,

neutropenia, and myelopathy resulted from a single cause rather than several

causes. He also omitted consideration of idiopathic causes for Marianne

Chapman’s CDM, additionally rendering his differential diagnosis unreliable. See

(“The failure to take into account the potential for

idiopathically occurring [disease]—particularly when [the disease] is a relatively

new phenomenon in need of further study—placed the reliability of [the expert’s]

conclusions in further doubt.”).


      Obviously, there were numerous potential causes for Marianne Chapman’s

CDM that Dr. Greenberg did not analyze or consider. The district judge

determined “Dr. Greenberg’s differential diagnosis is not reliable as a matter of

law in the Eleventh Circuit because he ruled-in and considered an etiology—

Fixodent-induced copper-deficiency myelopathy—that has not been established to

                                          27
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cause Ms. Chapman’s disease.” In re Denture Cream Prods. Liab. Litig., 795 F.

Supp. 2d at 1366. In reviewing the evidence presented and applying the applicable

law, we conclude the district judge did not abuse her discretion or commit manifest

error in precluding Dr. Greenberg’s expert testimony regarding the specific

causation of Marianne Chapman’s CDM.


      c. Exclusion of Other Expert Testimony


      Because the judge determined neither the general nor specific-causation

experts had proffered testimony that would prove the zinc in Fixodent had caused

Marianne Chapman’s CDM, she also excluded the testimonies of Dr. Wogalter and

Dr. Von Frunhofer, whose testimonies were premised on the toxicity of Fixodent.

In re Denture Cream Prods. Liab. 

.


      In short, taking everything together, there is enough data in the
      scientific literature to hypothesize causation, but not to infer it.
      Hypotheses are verified by testing, not by submitting them to lay
      juries for a vote. It may very well be that Fixodent in extremely large
      doses over many years can cause copper deficiency and neurological
      problems, but the methodology [the Chapmans’] experts have used in
      reaching that conclusion will not reliably produce correct
      determinations of causation.

testimony of Dr. Raffa concerned P&G’s assets, which related to

the punitive damages claim. Consequently, the judge precluded the proffered

testimonies of these experts based on Rule 702 relevancy. We conclude there was


                                        28
             Case: 12-14502     Date Filed: 09/11/2014    Page: 29 of 41


no abuse of discretion or manifest injustice in granting P&G’s motions preventing

the testimonies of these three experts for the Chapmans.


B. Summary Judgment


      After this court dismissed the parties’ first appeal for lack of jurisdiction,

based on our conclusion the Chapmans did not consider the district judge’s

Daubert order case-dispositive, the judge granted their Federal Rule of Civil

Procedure 60(b) motion for relief from the final judgment. Thereafter, P&G

moved for summary judgment and argued the Chapmans did not have an

admissible expert witness to establish general or specific causation. In opposition,

the Chapmans argued they had alternative expert witnesses to testify at trial,

irrespective of the district judge’s Daubert order. Concluding under the governing

law the Chapmans had no experts to prove their products liability case alleging

Fixodent was the cause of Marianne Chapman’s CDM, the district judge granted

summary judgment to P&G and entered final judgment.


      The Chapmans’ notice of appeal states they are appealing the summary

judgment order and final summary judgment entered on July 31, 2012, “as well as

all orders and rulings that produced that final judgment,” including the order

granting P&G’s motions to exclude the testimony of the Chapmans’ seven general

and specific expert witnesses. Notice of Appeal (Aug. 27, 2012). We have

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considered fully the district judge’s thorough Daubert order, which eliminated the

Chapmans’ expert witnesses, and concluded it was decided correctly under the

controlling law. We now address the summary judgment order the Chapmans have

appealed in conjunction with the Daubert order. 17


       We review a district judge’s granting summary judgment de novo. Williams

v. Mast Biosurgery USA, Inc., 

, 1318 (11th Cir. 2011). Summary

judgment is proper if the movant shows “there is no genuine dispute as to any

material fact and the movant is entitled to judgment as a matter of law.” Fed. R.

Civ. P. 56(a). When a party fails to proffer a sufficient showing “to establish the

existence of an element on which that party will bear the burden of proof at trial,”

there is no genuine dispute regarding a material fact. 

(citations, internal quotation marks, and ellipsis omitted). The burden for laying

the proper foundation for admission of expert testimony is on the party offering the

expert; admissibility must be shown by a preponderance of the evidence. 

n.10 (citing Bourjaily v. United States, 483
17
  Procedurally, this case has been appealed from the district judge’s order granting summary
judgment to P&G. Her Daubert order, excluding the Chapmans’ general and specific-causation
experts, alone could not have provided the procedural basis for appellate jurisdiction, because it
was not a final order. Consequently, the Chapmans have incorporated the judge’s Daubert order
in their appeal of summary judgment granted to P&G to have this court review the merits of the
Daubert order. The Chapmans’ reasons for appealing summary judgment granted to P&G were
raised before the district judge and decided in her order. The Chapmans’ opposition to P&G’s
summary judgment motion consisted of their proposing alternative experts for trial testimony,
while the Daubert order had addressed and excluded their general and specific-causation experts.
To the extent the Chapmans have appealed the same reasons for opposing P&G’s summary
judgment motion before the district judge, we address them.
                                               30
               Case: 12-14502       Date Filed: 09/11/2014      Page: 31 of 

, 175-76, 

, 2778-79 (1987)). “Evidence inadmissible at

trial cannot be used to avoid summary judgment.” Corwin v. Walt Disney Co., 

, 1249 (11th Cir. 2007) (citation, internal quotation marks, and alteration

omitted).


       The Chapmans opposed summary judgment for lack of expert witnesses

following the Daubert order for three reasons: (1) their expert, Dr. Joseph

Prohaska, a biochemistry professor at the University of Minnesota Medical School,

could testify at trial, because P&G had not contested his proffered testimony; (2)

they could call P&G experts and witnesses to testify that excessive ingestion of

zinc can lead to copper deficiency, which can cause CDM; and (3) Marianne

Chapman’s treating physicians for her neuropathy could testify regarding

causation. Because of the Chapmans’ “periodic and contradictory insistence on

having enough evidence to proceed to trial,” the judge analyzed the merits of

P&G’s motion to make her decision “perfectly clear” for this court. 18 Summ. J.

Order at 6. In granting summary judgment to P&G, the district judge addressed

the three possibilities for expert testimony the Chapmans had proffered following

18
   Because of the Chapmans’ joining in the interlocutory appeal purporting to be a final judgment
and her granting the Rule 60(b) motion, the judge was inclined to grant P&G’s motion for
summary judgment based on judicial estoppel under New Hampshire v. Maine, 

,

(2001). See 

121 S. Ct. at 1814 (“Where a party assumes a certain
position in a legal proceeding, and succeeds in maintaining that position, he may not thereafter,
simply because his interests have changed, assume a contrary position, especially if it be to the
prejudice of the party who has acquiesced in the position formerly taken by him.” (citation,
internal quotation marks, and alteration omitted)).
                                               31
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her Daubert order, precluding the testimonies of their general and specific

causation experts, and concluded their alternative expert witnesses also were

unavailing.


       On appeal, the Chapmans challenge both the district judge’s Daubert order

and summary judgment granted to P&G, because the cumulative effect of these

orders eliminated all potential causation experts the Chapmans had proffered.

Their arguments for alternative expert witnesses are combined in the Chapmans’

initial and reply briefs with their Daubert arguments, regarding their contention the

district judge erred in disqualifying their original causation experts. See, e.g.,

Appellants’ Br. at 18 n.5, 22-23, 25, 30-31, 40, 43, 44-46, 47, 48-49, 50, 56, 60;

Appellants’ Reply Br. at 4 n.1, 6, 8, 11, 14, 16-17, 18, 21, 22, 24, 30. The

alternative expert witnesses the Chapmans propounded following the Daubert

order and precluded by summary judgment granted to P&G necessarily had to

satisfy the same Daubert review standards to testify concerning causation for the

Chapmans to prove their case that Fixodent caused Marianne Chapman’s CDM.


       The Chapmans discuss Dr. Prohaska19 and P&G experts and witnesses 20 in

their initial and reply briefs in connection with their contention that the medical



19
  The Chapmans argue Dr. Prohaska’s Report states his “unchallenged opinion [by P&G] that
zinc excess causes copper deficiency and that copper deficiency caused [Marianne] Chapman’s
hematological symptoms.” Appellants’ Br. at 18 n.5.
                                             32
               Case: 12-14502       Date Filed: 09/11/2014        Page: 33 of 41




20
  In their initial brief, the Chapmans argue P&G pre-litigation studies, demonstrating the
bioavailability of zinc after ingestion, would support their position:

                Plaintiffs’ experts relied on three internal P&G studies demonstrating that
       a large percentage of the Fixodent used by denture wearers is ultimately ingested
       into the body and that the zinc in Fixodent, once ingested, is highly bioavailable
       in the small intestine, ultimately being absorbed into the bloodstream and leading
       to elevated serum zinc levels. In 1993, P&G performed a study of 10 actual
       denture wearers “to obtain data on the quantity of Zinc ions ingested by the study
       subjects following daily administration of the maximum recommended amount of
       [denture] adhesive paste.” P&G Clinical Study Report No. 003793, at 5 (Sept.
       1993) (“1993 Study”). Even when the study subjects were instructed to apply
       only half of the label’s recommended amount of adhesive, P&G found that the
       studied users ingested approximately 50% of the Fixodent applied. [Footnote 17
       to this sentence states: “At that rate, someone like Ms. Chapman would ingest 247
       mg of zinc daily (approximately 10 times the threshold for causing
       hypocupremia).”]
                Moreover, P&G internal studies dating back more than two decades have
       demonstrated that, once ingested, most of the elemental zinc dissociates from the
       Fixodent polymer and becomes free-floating in the intestines, where it affects
       copper metabolism. First, in 1989, prior to the introduction of Fixodent, P&G
       conducted a “zinc dissociation experiment” in which it mixed Fixodent with
       laboratory-simulated saliva, gastric fluid, and intestinal proteins. P&G calculated
       that “nearly 100% [of the zinc] dissociated (96.6%)” from its polymer when
       mixed with the simulated gastric fluid. P&G Report on Zinc Dissociation
       Experiment at 5 (July 1989). P&G further recognized that the zinc ions would
       bind with proteins in the small intestine, the precise mechanism by which zinc
       interferes with copper absorption (binding to metallothionein).
                Subsequently, in 1994, P&G performed an “[i]n vitro dialysis study” to
       further analyze the bioavailability of Fixodent. Consistent with its 1989 study,
       P&G found that 83.3% of the zinc in Fixodent became bioavailable when the
       denture cream was mixed with simulated gastric fluid (compared to 93% for zinc
       salt). P&G Dialysis Study on Denture Adhesives at 2 (Nov. 1994). The
       researchers responsible for the 1994 study noted that, “if the adhesive is ingested,
       . . . the majority of [the zinc will] be released” into the body, and as P&G had
       found the previous year, users ingest almost all of the Fixodent that they apply.
       As Dr. Brewer stated in his report, P&G’s own studies provide reliable evidence
       that the zinc in Fixodent can, if the adhesive is consumed, “caus[e] copper
       depletion and its clinical manifestations.” Brewer Rep. 9 & n.14.
                In excluding Plaintiffs’ general-causation experts, the district court never
       mentioned these studies or explained why they were not reliable in demonstrating
       the bioavailability of zinc in Fixodent. The court thus erred by failing to do the
       kind of “exacting analysis of the proffered expert’s methodology” that Daubert
       requires. That error was critical: given that it is well settled that zinc can cause
                                                33
               Case: 12-14502         Date Filed: 09/11/2014       Page: 34 of 41


community generally accepts excess zinc can cause CDM. Appellants’ Br. at 27-

33; Appellants’ Reply Br. at 3-6. Accepting this classification would place this

case in McClain category one, which would eliminate the Daubert analysis of the

Chapmans’ experts, if it were generally accepted by the medical community that

zinc causes CDM. We give the Chapmans “the benefit of the doubt” that these

first two sources of alternative expert witnesses have been presented on appeal in

their briefs. Carmichael v. Kellogg, Brown & Root Servs., Inc., 

,

1293 (11th Cir. 2009). The district judge noted “Dr. Prohaska’s report was limited

to hematological disorders, not myelopathy, and is therefore irrelevant.” Summ. J.

Order at 7. Although the Chapmans “may show zinc blocks copper absorption,

this alone cannot constitute a showing of general or specific causation.” 

see 

(noting causation evidence of one type of stroke “does

not apply to situations involving” another type of stroke). Moreover, she decided

“there was no mechanistic evidence regarding the absorption of zinc from Fixodent

itself.” Summ. J. Order at 8. In performing the requisite gatekeeping function, a

trial judge’s assessment of proposed testimony does not mean “‘taking the expert’s

word for it.’” 

(quoting Fed. R. Evid. 702 Advisory



       CDM, P&G’s own internal studies showing that Fixodent is ingested, and that
       when ingested exposes users to bioavailable zinc, constitute reliable evidence that
       zinc in Fixodent generally can cause CDM.

Appellants’ Br. at 44-46 (alterations and ellipsis in original) (some citations omitted).
                                                 34
               Case: 12-14502       Date Filed: 09/11/2014       Page: 35 of 41


Committee Notes (2000 Amends.)). We also conclude that Dr. Prohaska’s

testimony cannot provide admissible proof the Chapmans need to establish their

case at trial, because his expertise is hematology and not myelopathy at issue in

this case.


       In addition, the judge explained the Chapmans “cannot create a triable issue

of fact as to causation” with P&G experts and witnesses, who have not submitted

the requisite epidemiological or clinical reports. Summ. J. Order at 9. Expert

witnesses, who are expected to testify at trial, must be identified in the Joint

Pretrial Stipulation and must meet the procedural requirements of Federal Rule of

Civil Procedure 26(a)(2), including time designations for supplying disclosures and

reports, regarding expert testimony to be given. The Chapmans proposed their

ability to use P&G experts and witnesses at trial almost six months after the

judge’s scheduled January 24, 2011, deadline for identifying experts, making

complying with the procedural timely notice and disclosure requirements of Rule

26(a)(2), including reports of testimony, impossible. 21 See Fed. R. Civ. P.

26(a)(2)(D) (stating a party “must” disclose expert testimony “at the times and in


21
  Because the Chapmans had waited six months after the court-imposed deadline for naming
expert witnesses before proffering P&G’s experts to testify for them at trial, the district judge
recognized that they were procedurally barred from using these alternative witnesses at trial. We
are not saying parties may not use opposing parties’ experts to prove their case at trial as a
general proposition. We are recognizing that all experts, regardless of which party secured their
services, must meet the qualifications established by Daubert and the procedural requirements of
Rule 26(a)(2).
                                               35
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the sequence that the court orders”). “District courts have broad discretion to

exclude untimely disclosed expert-witness testimony.” Pride v. BIC Corp., 

, 578 (6th Cir. 2000).


       Even if the Chapmans had satisfied the procedural requirements of Rule

26(a)(2) to use P&G experts and witnesses to testify for them at trial, the district

judge concluded the Chapmans could not prove their case with them. P&G’s

experts had “reached the conclusion that Fixodent does not cause CDM.” 22 Summ.

J. Order at 9. The judge determined the Chapmans had “not made a sufficient

showing that [P&G’s] expert testimony would withstand the Daubert analysis of

[her] June 13 Order and yield the conclusion they seek, in view of [P&G’s]

experts’ testimony as a whole.” 

P&G witnesses ultimately did

not support the Chapmans’ conclusion that Fixodent caused Marianne Chapman’s

CDM, the judge explained the Chapmans “cannot perform an end run around the

[Daubert] Order by calling witnesses who have not been vetted for reliability.” 

also noted P&G’s expert, Dr. Laura W. Katzan, cannot “establish

22
   For example, P&G expert, Dr. Timothy R. Koch, plainly disagreed with the Chapmans’
general causation theory and stated: “It’s my position, based on an independent review of the
literature [and] based upon my own practice and experience, that there’s not a sufficient amount
of medical and scientific information and evidence available to support the statement that zinc
induces myelopathy.” Koch Dep. at 67:9-17. Similarly, the district judge noted the Chapmans
contended P&G expert, Dr. Lara W. Katzin, “confirmed that zinc-induced CDM should be
considered in the differential etiology for Ms. Chapman’s condition,” but failed to square that
statement with the judge’s discussion of Eleventh Circuit law stating general causation cannot be
proved by differential diagnosis, “a necessary element of their claims.” Summ. J. Order at 9
(citing 

) (citation and internal quotation marks omitted).
                                               36
               Case: 12-14502        Date Filed: 09/11/2014       Page: 37 of 41


general causation, a necessary element of their claims,” by differential diagnosis.

Id. (citing 

). Considering the prospective testimonies of

P&G experts and witnesses in context, the judge properly decided the Chapmans

could not prove their case with admissible evidence from these alternative experts

and witnesses.


       At a status conference the day after issuance of the Daubert order, the

Chapmans’ counsel argued for the first time they still could try to prove causation

through “treating experts who have opined [Marianne Chapman’s] condition was

caused by her use of Fixodent that were not the subject of the Daubert motion.”

Hr’g Tr., June 14, 2011, at 7:21-8:1 (emphasis added). In recasting Marianne

Chapman’s treating physicians as “treating experts,” the Chapmans sought to have

these doctors testify concerning their personal treatment of Marianne Chapman as

well as their view of the cause of her CDM. The judge, however, explained in her

summary judgment order that treating physicians, who diagnosed Marianne

Chapman’s CDM, are fact and not expert witnesses. 23 Summ. J. Order at 10




23
   A treating physician providing lay testimony can testify narrowly, limited to personal
knowledge resulting from providing medical care, involving consultation, examination, or
treatment of a patient plaintiff. See United States v. Henderson, 

, 1300 (11th Cir.
2005) (distinguishing between an oral surgeon’s testimony that a patient had a fractured jaw as
opposed to giving a hypothesis as to the cause). But “a treating doctor . . . is providing expert
testimony if the testimony consists of opinions based on ‘scientific, technical, or other
specialized knowledge’ regardless of whether those opinions were formed during the scope of
                                                37
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(citing Hendrix, 

). The Chapmans have not briefed on appeal their

district-court argument in opposing summary judgment that Marianne Chapman’s

treating physicians could testify as experts at trial. “The ‘law is by now well

settled in this Circuit that a legal claim or argument that has not been briefed

before the court is deemed abandoned and its merits will not be addressed.’”

(quoting Access Now, Inc. v. Sw. Airlines Co., 

, 1330 (11th Cir. 2004)). Consequently, we conclude the Chapmans

have abandoned on appeal their argument that Marianne Chapman’s treating

physicians could have testified as experts at trial. Because none of the Chapmans’

alternative sources for expert witnesses could provide evidence admissible at trial

“to avoid summary judgment,” the district judge appropriately granted summary

judgment to P&G. 

(citations and internal quotation

marks omitted).


                                        III. CONCLUSION


       To prove Fixodent caused Marianne Chapman’s CDM, the Chapmans were

required to have Daubert-qualified, general and specific-causation-expert

testimony that would be admissible at trial to avoid summary judgment. Guinn,


interaction with a party prior to litigation.” Musser v. Gentiva Health Servs., 

, 757
n.2 (7th Cir. 2004) (quoting Fed. R. Evid. 702(a)).



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. With the district judge’s properly analyzed Daubert order, the

Chapmans lost their designated general and specific-expert witnesses, because of

deficiencies in the experts’ scientific-methodology reliability. Their attempts to

proffer alternative causation-expert witnesses failed, because their prospective

testimony was inadmissible substantively, procedurally, or abandoned on appeal.

Summary judgment correctly was granted to P&G.


      AFFIRMED.




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JORDAN, Circuit Judge, concurring:

      Given the “due deference” that the abuse of discretion standard embodies,

see Gall v. United States, 

, 59 (2007), and the “range of choice”

permitted by that standard, see In re Rasbury, 

, 168 (11th Cir. 1994), I

agree that we should affirm the district court’s exclusion of the Chapmans’ general

causation experts. I would, therefore, not address any of the other issues raised by

the Chapmans.

      Specifically, I would not suggest, as the court does in dictum, that the

district court could have properly prevented the Chapmans from relying on Procter

& Gamble’s own experts. The district court addressed the Chapmans’ reliance on

some of the defense experts on the merits and did not exclude those experts under

Rule 26 of the Federal Rules of Civil Procedure.          So there is no need to

hypothesize about how we would rule if the district court had decreed that such

reliance by the Chapmans was procedurally improper. Moreover, P&G does not

assert Rule 26 on appeal, and some cases hold that, because there is no surprise or

prejudice, a party is permitted to use and rely on the expert testimony presented by

the opposing party.     See, e.g., Nat’l Railroad Passenger Corp. v. Certain

Temporary Easements, 

, 42 (1st Cir. 2004) (no abuse of discretion in

allowing plaintiff to call defense expert in its case-in-chief); Kerns v. Pro-Foam of

South Alabama, 

, 1309-12 (S.D. Ala. 2007) (failure of plaintiff


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to disclose defendant’s expert as its own expert did not prevent plaintiff from

calling that expert during its case-in-chief). If we are going to opine on this issue,

we should wait for a case which directly presents it.

      In closing, I recognize that the district court at times used language which

might be seen as opining on the ultimate persuasiveness of the theories advanced

by the Chapmans’ experts. But given its numerous accurate statements of the

correct standard under Daubert v. Merrell Dow Pharmaceuticals, Inc., 

(1993), I do not think the district court applied an incorrect (or improperly

onerous) legal standard.




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