                               FIFTH DIVISION
                              MCFADDEN, P. J.,
                          RICKMAN and MARKLE, JJ.

                   NOTICE: Motions for reconsideration must be
                   physically received in our clerk’s office within ten
                   days of the date of decision to be deemed timely filed.
                               http://www.gaappeals.us/rules


                                                                  February 25, 2019




In the Court of Appeals of Georgia
 A18A1842. KERSHAW et al. v. PRINCETON PROPERTIES
     MANAGEMENT, INC. et al.

      MARKLE, Judge.

      Mr. and Mrs. James and Delores Kershaw, plaintiffs in the civil action below,

appeal from the trial court’s grant of summary judgment to the defendants. The

Kershaws argue that the trial court erred in finding that they failed to submit

sufficient expert medical evidence to establish that negligence by the defendants

caused the Kershaws’ injuries. Because we conclude that the trial court must exercise

its role as gatekeeper to determine the admissibility of expert testimony under OCGA

§ 24-7-702 and Daubert v. Merrell Dow Pharmaceuticals, 509 U.S. 579 (113 SCt

2786, 125 LE2d 469) (1993), and the trial court did not do so in this case, we vacate

the trial court’s order and remand the case for further proceedings.
      “Summary judgment is proper when there is no genuine issue of material fact

and the movant is entitled to judgment as a matter of law.” OCGA § 9-11-56 (c). Our

review of a trial court’s ruling on a motion for summary judgment is de novo, and we

review the evidence, and all reasonable inferences, in the light most favorable to the

nonmovant. See Green v. Raw Deal, Inc., 290 Ga. App. 464, 465 (659 SE2d 856)

(2008).

      So viewed, the evidence shows that Mr. and Mrs. Kershaw rented an apartment

in the Highland Lakes Apartments complex from May 2012 to June 2015. Mrs.

Kershaw was diagnosed with COPD in November 2011, and the Kershaws believe

that mold in the apartment exacerbated Mrs. Kershaw’s condition. As evidence of

mold in the apartment, the Kershaws testified that they noticed rust-like stains on the

air conditioner vents and moisture damage near the water heater, and the stains and

moisture reappeared after cleaning. The apartment also smelled bad, and the

Kershaws sometimes burned incense to cover the smell. In addition, the Kershaws

hired Healthy Air to perform a mold test and the test showed that the apartment had

very high toxic mold levels.

      As evidence of her medical condition, Mrs. Kershaw testified that she never

needed medication for breathing issues until she lived in Highland Lakes. Even after

                                          2
she moved out of the apartment, Mrs. Kershaw continued to experience a weakened

immune system. Prednisone and Z-Packs help her symptoms and her doctors have

told her that mold exposure can cause health issues. Mr. Kershaw testified that his

health was also affected by the mold at Highland Lakes. He has experienced a loss

of memory, chronic phlegm in his throat, an overactive bladder, and headaches.

      Dr. Vosudeh Pai, Mrs. Kershaw’s treating physician, testified in a deposition

as an expert witness for the Kershaws. He stated that, as a general principle, mold

exposure can exacerbate respiratory symptoms and pulmonary conditions. Dr. Pai did

not order any lab testing to determine if Mrs. Kershaw had been exposed to an unsafe

level of mold, or to determine if she is allergic to any type of mold. He acknowledged

that mold spores are present in “background levels” in outdoor air, and he could not

identify how much greater exposure Mrs. Kershaw had by virtue of the indoor air

compared to the outdoor air. Dr. Pai also acknowledged that inhalation of incense

smoke could aggravate Mrs. Kershaw’s condition.

      Dr. Pai explained that COPD is a progressive condition that causes breathing

difficulties and wheezing. In his view, Mrs. Kershaw’s condition was caused by her

years of cigarette smoking and was “[d]efinitely not” caused by mold exposure. Dr.

Pai looked through medical records of Mrs. Kershaw’s visits to various emergency

                                          3
rooms while she was renting the Highland Lakes apartment, when she presented with

breathing difficulties. He testified that several of those flare ups may have been

triggered by things like seasonal pollen in the air, exposure to someone who was sick,

or exposure to cigarette smoke (either because she was smoking herself or because

she had been near someone who was smoking). Dr. Pai further testified that several

of the flare ups appeared to have been triggered during a time when Mrs. Kershaw

was away from her Highland Lakes apartment. Additionally, he stated that the

frequency of flare ups reported by Mrs. Kershaw were typical for a patient with

COPD. Ultimately, as of Mrs. Kershaw’s most recent visit in May 2017, Dr. Pai did

not notice any worsening of her condition. He described her pulmonary function

between 2012 to 2016 as “fairly stable.” Based on medical records and clinical notes

that were created contemporaneously to that time period, Mrs. Krenshaw’s flare ups

did not appear to have become worse, more severe, or more frequent during the time

she lived at Highland Lakes.

      Nonetheless, Dr. Pai testified that he was able to state with a reasonable degree

of medical certainty that Mrs. Kershaw’s COPD was exacerbated by her exposure to

mold at the Highland Lakes apartment. He explained that this opinion was based on

Mrs. Kershaw’s statements to Dr. Pai that she had seen mold in her apartment, and

                                          4
on pictures of the apartment which she showed him when she was seeking treatment.

He concluded that there was “a reasonable veracity” to her assertion that she had been

exposed to mold, and explained that it is generally known that mold exposure can

aggravate respiratory symptoms in patients with COPD. Dr. Pai could not, however,

isolate the effect of the mold exposure from the effect of other potential triggers.

      The Kershaws filed a civil action against the entities that own Highland Lakes,

raising claims of private nuisance, breach of the implied warranty of habitability, and

breach of the covenant of quiet enjoyment, and alleging that the defendants had failed

to remediate the mold and dust in the apartment and that they experienced injury and

damages as a result. The defendants filed a motion to exclude Dr. Pai as an expert

witness, arguing that his testimony did not meet the requirements of OCGA § 24-7-

702 and Daubert v. Merrell Dow Pharmaceuticals, 509 U.S. 579 (113 SCt 2786, 125

LE2d 469) (1993). The defendants also filed a motion for summary judgment, arguing

that the Kershaws had failed to present the medical expert testimony necessary to

establish that any negligence by the defendants caused their injuries. Without ruling

on the motion to exclude Dr. Pai’s testimony, the trial court granted the defendants’

motion for summary judgment, finding that “Dr. Pai’s conclusions that mold and dust

exacerbated Mrs. Kershaw’s COPD are speculative, unsupported by his clinical

                                          5
observations, and therefore do not rise to the required level of ‘reasonable

probability.’”1 The Kershaws then filed this appeal.

      On appeal, the Kershaws argue that Dr. Pai’s testimony satisfied the

requirement for expert testimony as to causation in this case. They acknowledge that

Dr. Pai did not run any tests to confirm Mrs. Kershaw had been exposed to mold but

contend that his failure to do so does not mean that his opinion lacks a scientific

basis. Instead, they assert, the lack of testing is merely a factor the jury may consider

when evaluating the weight to afford his opinion.

             Causation is an essential element of nuisance, trespass, and
      negligence claims. To establish proximate cause, a plaintiff must show
      a legally attributable causal connection between the defendant’s conduct
      and the alleged injury. The plaintiff must introduce evidence which
      affords a reasonable basis for the conclusion that it is more likely than
      not that the conduct of the defendant was a cause in fact of the result.


(Punctuation omitted). Lore v. Suwanee Creek Homeowners Assn., 305 Ga. App. 165,

172 (2) (699 SE2d 332) (2010). “The diagnosis and potential continuance of a disease

or other medical condition are medical questions to be established by physicians as


      1
        The trial court also found that the Kershaws had failed to present any
evidence of property damage due to the mold. The Kershaws do not challenge this
finding on appeal.

                                           6
expert witnesses and not by lay persons. Thus, we have required expert medical

testimony, based at least on reasonable probability, to establish a causal link between

exposure to a substance and a medical condition.” (Citation omitted.) Seymour Elec.

& Air Conditioning Svc., Inc. v. Statom, 309 Ga. App. 677, 680 (710 SE2d 874)

(2011). Where, as here, the case involves a “specialized medical” question, expert

testimony is required to establish causation. Id. at 679-680.

      OCGA § 24-7-702 (“Rule 702”) governs the admissibility of expert testimony

and requires that the trial court act as “gatekeeper to ensure the relevance and

reliability of expert testimony.” (Citation and punctuation omitted.) Scapa Dryer

Fabrics, Inc. v. Knight, 299 Ga. 286, 289 (788 SE2d 421) (2016) (addressing expert

testimony under former OCGA § 24-9-67.1). OCGA § 24-7-702 (b) 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,
      if: (1) The testimony is based upon sufficient facts or data; (2) The
      testimony is the product of reliable principles and methods; and (3) The
      witness has applied the principles and methods reliably to the facts of
      the case which have been or will be admitted into evidence before the
      trier of fact.



                                          7
      “Though Daubert involved scientific experts, the Supreme Court has since

made it clear that the strictures of Rule 702 and Daubert apply with equal force to

non-scientific expert witnesses.” (Citation omitted.) Smith v. CSX Transp., Inc., 343

Ga. App. 508, 511-512 (1) (b) (806 SE2d 890) (2017). Accordingly, a medical

doctor’s opinion regarding causation falls within OCGA § 24-7-702 and must satisfy

Daubert. Id. at 512.

      To establish the admissibility of expert testimony under Rule 702, the trial

court, as gatekeeper, must consider: (a) the qualifications of the expert; (b) the

reliability of the testimony; and (c) the relevance of the testimony. Scapa Dryer

Fabrics, Inc., 299 Ga. at 289. Thus, Rule 702 “imposes a special obligation upon the

trial judge” to act as “gatekeeper.” Scapa Dryer Fabrics, Inc., 299 Ga. at 289 (citing

Kumho Tire Co. v. Carmichael, 526 U. S. 137, 147 (II) (A) (119 SCt 1167, 143 LE2d

238) (1999)); see also Dubois v. Brantley, 297 Ga. 575, 585(2) (775 SE2d 512)

(2015).

      [W]hen a party offers expert testimony and the opposing party raises a
      Daubert challenge, the trial court must make certain that an expert,
      whether basing testimony upon professional studies or personal
      experience, employs in the courtroom the same level of intellectual rigor
      that characterizes the practice of an expert in the relevant field. . . .
      Daubert requires the trial court to act as a gatekeeper to insure that

                                          8
      speculative and unreliable opinions do not reach the jury. As a
      gatekeeper the court must do a preliminary assessment of whether the
      reasoning or methodology underlying the testimony is scientifically
      valid and of whether that reasoning or methodology properly can be
      applied to the facts in issue.


(Citations and punctuation omitted; emphasis supplied.) McClain v. Metabolife Intl.,

Inc., 401 F3d 1233, 1237 (II) (11th Cir. 2005).2 We will not disturb a trial court’s

determination of whether an expert is qualified – and thus the testimony is admissible

– absent a manifest abuse of discretion. HNTB Ga., Inc. v. Hamilton–King, 287 Ga.

641, 642 (1) (697 SE2d 770) (2010). “A trial court, however, abuses its discretion by

failing to act as a gatekeeper.” McClain, 401 F3d at 1238 (II).

      Here, the defendant moved to exclude the expert’s testimony under Daubert.

The trial court did not rule on the motion, but instead evaluated whether the expert’s




      2
          Because our new Evidence Code is modeled after the federal rules, in
interpreting Georgia’s new Evidence Code, we may “look to decisions of the federal
appellate courts construing and applying the Federal Rules, especially the decisions
of the United States Supreme Court and the Eleventh Circuit.” Chrysler Group, LLC
v. Walden, 303 Ga. 358, 361 (II) (A) (812 SE2d 244) (2018); see also OCGA § 24-7-
702 (f). If the provisions at issue were “carried over from our old Evidence Code, and
when courts consider the meaning of those provisions, they may rely on Georgia
decisions under the old Code.” (Citations omitted.) Chrysler Group, LLC, 303 Ga. at
361 (II) (A).

                                          9
testimony established causation and granted summary judgment to the defendants

based on that ground. In doing so, the trial court failed to act in its role as gatekeeper.

       Moreover, the trial court’s order, which addresses the expert’s testimony in a

single sentence, shows that the trial court considered only whether the testimony

established a question of fact on causation. There is no mention or discussion of the

expert’s qualifications, the reliability of his testimony, or the relevance of the

testimony. See Scape Dryer Fabrics, Inc., 299 Ga. at 289. Thus, the order does not

enable us to evaluate whether the trial court considered the admissibility of the

expert’s testimony under OCGA § 24-7-702.3 Because this is a role for the trial court,

and our review is limited to determining whether the trial court abused its discretion,

we conclude that we must vacate the trial court’s order and remand for the trial court

to conduct a proper Daubert analysis. See Lavelle v. Laboratory Corp. of America,

327 Ga. App. 142, 147 (2) (755 SE2d 595) (2014) (“While the trial court was not

required to make specific findings of fact relating to these statutory requirements


       3
         We are mindful that we generally presume that the trial court performed its
duties, Byelick v. Michel Herbelin USA, Inc., 275 Ga. 505, 507 (3) (570 SE2d 307)
(2002), but where the trial court did not rule on the pending motion to exclude, did
not mention the admissibility of the expert’s testimony, and explicitly stated that it
was considering the motion for summary judgment, we cannot say with certainty that
the trial court conducted the proper Daubert analysis.

                                            10
[under Rule 702], the trial court’s rulings did not adequately demonstrate that the trial

court performed its role as gatekeeper . . . . For this reason, we vacate the ruling

excluding [the expert’s] opinion and remand the case” for the trial court to fulfill its

role as gatekeeper.) (citations and punctuation omitted).

      Judgment vacated and case remanded with instruction. Rickman, J. concurs.

McFadden, P. J.,dissents.

      * THIS OPINION IS PHYSICAL PRECEDENT ONLY. COURT OF

APPEALS RULE 33.2.




                                           11
In the Court of Appeals of Georgia
 A18A1842. KERSHAW et al. v. PRINCETON PROPERTIES
     MANAGEMENT, INC. et al.

      MCFADDEN, Presiding Judge, dissenting.

      In vacating the trial court’s judgment, the majority concludes that the trial court

erred by failing to perform his gatekeeping duties under OCGA § 24-7-702 (“Rule

702”). But the record does not affirmatively show this failure, so I respectfully

dissent. Instead of vacating the judgment and remanding the case to the trial court, I

would reach the merits of the appeal and, as detailed below, reverse the grant of

summary judgment on the claims requiring proof that the exacerbation of Mrs.

Kershaw’s medical condition was caused by the presence of mold or dust in the

apartment.

      1. Rule 702 ruling.


                                           2
      As the majority notes, the trial court was required to decide whether Dr.

Vosudeh Pai’s opinion testimony was admissible under Rule 702 before deciding

whether that testimony was evidence of medical causation sufficient to preclude

summary judgment. See generally Williams v. Mast Biosurgery USA, 644 F3d 1312,

1317-1318 (II) (A) (11th Cir. 2011) (“when a treating physician’s testimony is based

on a hypothesis, not the experience of treating the patient, it crosses the line from lay

to expert testimony, and it must comply with the requirements of Rule 702 and the

strictures of Daubert”). The majority opinion rests on a determination that the trial

court did not fulfill this requirement, and therefore erred. But the record does not

support this determination.

      A “trial court is presumed to know the law and presumed to faithfully and

lawfully perform his or her duties. We will not presume the trial court committed

error where that fact does not affirmatively appear in the record.” Johnson v.

Equicredit Corp., 238 Ga. App. 380 (1) (517 SE2d 353) (1999) (citations omitted).

This rule applies to the question of whether a trial court performed its role as

gatekeeper over the admission of expert testimony. See Lavelle v. Laboratory Corp.

of America, 327 Ga. App. 142, 147 (2) (755 SE2d 595) (2014).



                                           3
      In this case, “[t]here is nothing in the record establishing a failure of the trial

court to consider the [admissibility of Dr. Pai’s testimony on medical causation], and

under the principle that a trial court will be presumed to have performed [his] duty we

[should] not assume the trial court here failed to do so.” Byelick v. Michel Herbelin

USA, 275 Ga. 505, 507 (3) (570 SE2d 307) (2002) (citations omitted). While the trial

court did not expressly rule on the defendants’ motion to exclude Dr. Pai’s opinion

testimony, we may infer from the record as a whole that the trial court considered the

admissibility of the testimony in the course of ruling on the summary judgment

motion. Throughout the course of the litigation below, the defendants argued to the

trial court that he would have to act as a gatekeeper in connection with the medical

causation evidence. The defendants argued this point first in their motion to dismiss

the action, which the trial court denied. They then argued the point in their motion to

exclude Dr. Pai’s testimony, and they reiterated the argument in support of their

motion for summary judgment. As the defendants made clear in their brief supporting

their summary judgment motion, the trial court would not need to reach their

argument that Dr. Pai’s opinion failed to establish causation if the trial court

determined that the opinion was inadmissible under Rule 702. The fact that the trial

court did reach this causation argument indicates that the trial court considered, and

                                           4
rejected, the defendants’ assertion that Daubert required the exclusion of Dr. Pai’s

testimony regarding a causal link between exposure to mold and the exacerbation of

a respiratory condition. This would not be a remarkable conclusion on the part of the

trial court. Daubert’s role is to “ensur[e] that the courtroom door remains closed to

junk science[; it] is not served by excluding testimony . . . that is supported by

extensive relevant experience, and . . . exclusion is rarely justified in cases involving

medical experts.” Cartledge v. Montano, 325 Ga. App. 322, 328 (1) (750 SE2d 772)

(2013) (citation and punctuation omitted).

      Simply put, nothing in the trial court’s summary judgment order is inconsistent

with the presumption that the trial court performed his duties under Rule 702 before

considering whether Dr. Pai’s opinion created a genuine issue of material fact.

Compare Lavelle, 327 Ga. App. at 145-147 (2) (record did not adequately

demonstrate that trial court performed role as gatekeeper where language of trial

court’s written order suggested that trial court overlooked some bases for witness’s

expert opinion testimony in conducting Daubert). So I believe we may — and should

— reach the question of whether the trial court erred in granting the defendants’

motion for summary judgment.

      2. Summary judgment.

                                           5
      Delores Kershaw does not contend that the mold and dust in the subject

apartment caused her medical condition. She was diagnosed before she moved in. She

contends, and elicited expert testimony showing, “with a reasonable degree of

medical probability,” that the mold and dust “made a meaningful contribution to her

exacerbation.” That is sufficient.

      “It is well established that recovery may be had for aggravation of a

pre-existing condition or disease.” Binns v. MARTA, 168 Ga. App. 261, 264 (3) (308

SE2d 674) (1983) (citation omitted); see also Scapa Dryer Fabrics, Inc. v. Knight,

299 Ga. 286 (788 SE2d 421) (2016). Dr. Pai’s expert testimony created a genuine

issue of material fact as to whether Mrs. Kershaw’s exposure to mold aggravated her

condition. His testimony followed the roadmap provided by this court in Allstate Ins.

Co. v. Sutton, 290 Ga. App. 154 (658 SE2d 909) (2008), and by our Supreme Court

in Scapa Dryer Fabrics, Inc. v. Knight, supra. So the Kershaws are entitled to survive

summary judgment on their claims requiring proof that the exacerbation of Mrs.

Kershaw’s condition was caused by the presence of mold or dust in the apartment.1




      1
        I find no error with the grant of summary judgment to the defendants on the
claims for property damage and for breach of the covenant of quiet enjoyment.

                                          6
      Under Allstate “we have required expert medical testimony, ‘based at least on

reasonable probability,’ to establish a causal link between exposure to a substance

and a medical condition.” 290 Ga. App. at 160 (3) (b) (citation omitted). Under Scapa

that evidence is required to show that the exposure “made a meaningful contribution”

to the exacerbation of the condition. 299 Ga. at 291 (emphasis omitted). Accordingly,

the Kershaw’s expert, Dr. Pai, opined with a reasonable degree of medical probability

that Mrs. Kershaw’s exposure to mold or dust in her apartment meaningfully

contributed to the exacerbation of that medical condition. His opinion therefore

established the required “causal link between exposure to a substance and a medical

condition.” Allstate, supra (citation omitted).

      At issue before us is the basis for Dr. Pai’s opinion. In the summary judgment

order the trial court held that Dr. Pai’s opinion was not evidence of the necessary

causal link because it was “speculative [and] unsupported by his clinical

observations.” These criticisms go to the weight and credibility of Dr. Pai’s testimony

and should be addressed by the factfinder. See Cartledge v. Montano, 325 Ga. App.

322, 328 (1) (750 SE2d 772) (2013)2 (“the credibility of the expert and the weight to

      2
        See generally Evans v. Dept. of Transp., 331 Ga. App. 313, 318 (2) n. 2 (771
SE2d 20) (2015) (cases decided under former Evidence Code remain useful to
analysis of expert testimony and speculation).

                                          7
be given to his opinion [are] matters to be addressed by the jury”) (citations and

punctuation omitted). Our Supreme Court corrected a similar error in Layfield v.

Dept. of Transp., 280 Ga. 848 (632 SE2d 135) (2006). Reversing a ruling by this

court that a defendant was entitled to summary judgment because the plaintiff’s

expert witness lacked sufficient information to reach a probative opinion, the Court

held in Layfield that, even if an

      expert’s opinion was based upon inadequate knowledge, this does not
      mandate the exclusion of the opinion but, rather, presents a jury question
      as to the weight which should be assigned the opinion. If it be developed
      that the opinion is based on inadequate knowledge, this goes to the
      credibility of the witness rather than to the admissibility of the evidence.
      The weight given to expert testimony in negligence cases is for the trier
      of fact who can, but is not required to give it controlling influence.


Id. at 851 (1) (citations and punctuation omitted). Unless an expert’s opinion is

wholly speculative, “[a]ny objection to the speculation of [that] opinion goes to the

testimony’s weight, not its admissibility.” DeGolyer v. Green Tree Servicing, LLC,

291 Ga. App. 444, 451 (5) (b) (662 SE2d 141) (2008) (citation omitted). Accord

Layfield, supra.

      Dr. Pai’s opinion was not wholly speculative. As Mrs. Kershaw’s treating

physician he was personally familiar with her medical history and condition and he

                                           8
received information from her regarding her exposure to mold in her apartment. And

he was permitted to give an expert opinion based on Mrs. Kershaw’s report that there

was mold in her apartment, even though this fact was not in his personal knowledge.

See Leonard v. State, 269 Ga. 867, 870 (3) (506 SE2d 853) (1998) (expert may give

opinion based on his own examination or observation or “upon any state of facts,

supported by some evidence in the case, which he assumes as true”) (citation,

punctuation, and emphasis omitted). “[W]here evidence in the case allows a

reasonable inference to be drawn by the expert witness, the expert may render an

opinion for the jury to weigh.” Cartledge, 325 Ga. App. at 327-328 (1) (citation and

punctuation omitted).

      Dr. Pai opined that, to a reasonable degree of medical probability, Mrs.

Kershaw’s exposure to mold or dust meaningfully contributed to the exacerbation of

her condition. His opinion satisfied the requirements of Scapa, supra, and Allstate,

supra. At this stage of the proceedings Dr. Pai’s testimony must be “treated with

indulgence,” even if it ultimately does not persuade a jury. Layfield, 280 Ga. at 850

(1). Given that testimony, we should reverse the grant of summary judgment on the

claims that mold or dust in the apartment exacerbated Mrs. Kershaw’s medical

condition.

                                         9
