Affirmed and Memorandum Opinion filed August 10, 2023.

In The

Fourteenth Court of Appeals

NO. 14-22-00301-CV

RAWNEY CHARLES MCVANEY, Appellant

V.

BAYLOR SCOTT & WHITE MEDICAL CENTER – LAKEWAY; KIRBY 

DALE REED, N.P.; KRISTIE LEE MILLER, M.D.; AND EPLRMC, P.A.,

Appellees

On Appeal from the 353rd District Court

Travis County, Texas

Trial Court Cause No. D-1-GN-19-001953

MEMORANDUM OPINION

Appellant Rawney Charles McVaney presented to the Baylor Scott & White 

Medical Center–Lakeway (the hospital) in Travis County with unexplained 

weakness and tingling in his extremities. After several hours, McVaney requested a 

discharge from the hospital because he believed had not received proper care and 

had not received a satisfactory explanation for his worsening symptoms. McVaney 

was later diagnosed at another area medical facility with Guillain-Barré Syndrome
2

(GBS), a relatively rare neurological condition.

In this appeal, we must determine whether the trial court erred in rendering

summary judgment on the ground that McVaney produced no evidence of the 

causation required for his medical-malpractice claims against appellees the 

hospital, Kirby Dale Reed, N.P., Kristie Lee Miller, M.D. and EPLRMC, P.A. 

Concluding the trial court did not err, we affirm the judgment of the trial court.1

I. BACKGROUND

McVaney, now a 64-year-old man with a previously unremarkable medical 

history, woke up with tingling in his extremities and weakness in his legs on the 

morning of February 20, 2018. After his symptoms worsened through the morning,

McVaney’s wife drove him to the emergency department at the hospital around

11:30 a.m. The hospital’s medical records reflect that McVaney was able to walk 

and stand without assistance at the time of his admission.

Despite the fact no doctor ever spoke with or physically examined

McVaney, the hospital’s medical records recite the following diagnoses: “R53.1 

Weakness; R20.2 Paresthesia of both hands; R20.2 Paresthesia of both feet; R42 

Dizziness; and Z56.6 Work Stress.” McVaney’s condition continued to worsen

after his admission, and he became frustrated that the hospital’s staff had not 

diagnosed or treated his condition. Nurse practitioner Kirby Dale Reed discussed 

the possibility of sleep apnea, suggested a sleep study, as well as an MRI for 

further diagnostics. McVaney requested a discharge five and a half hours after his 

1 The Supreme Court of Texas ordered the Court of Appeals for the Third District of 

Texas to transfer this appeal (No. 03-22-00132-CV) to this court. Misc. Docket No. 22-9025

(Tex. March 29, 2022); see Tex. Gov’t Code Ann. §§ 73.001, .002. Because of the transfer, we 

decide the case in accordance with the precedent of the transferor court under principles of stare 

decisis if our decision otherwise would have been inconsistent with the transferor court’s 

precedent. See Tex. R. App. 41.3.
3

admission in what McVaney described in his petition as a quadriplegic state, being 

unable to walk or stand.

McVaney’s wife contacted a friend who was married to Dr. Richard Van 

Boven, a local neurologist unaffiliated with the hospital. Dr. Van Boven came to 

McVaney’s home shortly after his discharge from the hospital, examined him, 

suspected he had GBS, and called an ambulance. McVaney was then transported to 

Seton Medical Center in Austin where he began receiving intravenous 

immunoglobulin treatment after medical staff at Seton suspected that he was 

suffering from GBS. Though the parties dispute the length of the delay in 

treatment, it is undisputed that McVaney began receiving treatment for his GBS 

less than 24 hours after the onset of his symptoms.

GBS is an acute neurological condition that generally begins with symptoms 

of numbness, tingling sensation in extremities, weakness, pain in the limbs or some 

combination of these symptoms. See Nobuhiro Yuki, M.D. and Hans-Peter 

Hartung, M.D., Guillain-Barré Syndrome, N. Eng. J. Med. 2012, 366:2295.

2 “The 

main feature is progressive bilateral and relatively symmetric weakness of the 

limbs, and the weakness progresses over a period of 12 hours to 28 days before a 

plateau is reached.” Id. Unfortunately, the disease has a poor and often severe

prognosis:

In the majority of patients, the Guillain–Barré syndrome continues to 

progress for up to 1 to 3 weeks after the onset of symptoms. Two 

thirds of patients are unable to walk independently when maximum 

weakness is reached. Respiratory insufficiency occurs in 25% of 

patients, and major complications, including pneumonia, sepsis, 

pulmonary embolism, and gastrointestinal bleeding, develop in 60%

of intubated patients. Among severely affected patients, 20% remain 

2 This article was relied on by McVaney’s expert, Dr. Van Boven and attached to the

expert report.
4

unable to walk 6 months after the onset of symptoms. The variations 

in the rate and extent of recovery in the Guillain–Barré syndrome 

make prognostication difficult.

Id. at 2296. Despite immunotherapy, “up to 20% of patients remain severely 

disabled and approximately 5% die.” Id. at 2294.

After his admission to Seton, McVaney continued to deteriorate reaching his 

plateau some weeks later. Following his hospitalizations, McVaney experienced 

some recovery and improvement. In 2021, McVaney gave his deposition and 

testified he was then able to walk independently for short distances, walk with the 

aid of a cane for longer distances, and drive a vehicle without modifications. 

Though he returned to work part time, GBS has left him with physical limitations 

and constant pain in his legs.

In April 2019, McVaney filed a medical-malpractice claim subject to Civil 

Practice and Remedies Code chapter 74 against the hospital, Kristie Lee Miller, 

M.D., Kirby Dale Reed, N.P., and EPLRMC, P.A.3 for failure to timely diagnose 

his GBS and begin appropriate treatment.

4 McVaney’s petition states that this 

failure to diagnose and treat led to an increased severity of his GBS and resulted in

“permanent paralysis resulting in permanent disability, disfigurement and 

[e]conomic loss.” Kristie Lee Miller, M.D. was McVaney’s attending physician at 

the hospital, who electronically signed his medical records.5 Reed, a nurse 

3 EPLRMC, P.A. is the professional association which employed Dr. Kristie Miller.

4 Tex. Civ. Prac. & Rem. Code Ann. §§ 74.001–.507 (popularly known as Texas Medical 

Liability Act (TMLA)).

5 Dr. Miller, the attending physician, electronically signed McVaney’s medical records 

agreeing to the following statement: “I have seen and examined the above patient.” Although not 

pertinent to the causation issue before us, this attestation was investigated by the Texas 

Department of State Health Services (DSHS) after Dr. Van Boven lodged a complaint on behalf 

of McVaney because Dr. Miller allegedly never physically examined McVaney or spoke with

him.
5

practitioner at the hospital, also signed McVaney’s medical records and agreed to 

McVaney’s treatment plan. McVaney subsequently amended his petition to add 

claims against all defendants for violations of the Emergency Medical Treatment & 

Labor Act, a federal statute. See 42 U.S.C. § 1395dd(a).6

In 2021, the defendants collectively filed a traditional and no-evidence 

motion for summary judgment on the issue of causation. McVaney, in response,

argued that his neurology expert Dr. Van Boven established that defendants’

violations of the standard of care proximately caused the increased severity of his 

GBS. After hearing the summary-judgment motions, the trial court granted the 

defendants’ no-evidence motion as to McVaney’s claims against the defendants. 

McVaney now appeals from the final judgment of the trial court.7

II. ANALYSIS

On appeal, McVaney argues that the trial court erred in rendering summary 

judgment because reasonable minds could differ as to whether immunotherapy

treatment earlier in the day would have slowed the progression of his disease. 

Therefore, he asserts a fact issue precluded summary judgment.

6 Popularly known as the Emergency Medical Treatment and Labor Act (EMTALA). In 

his petition, McVaney incorrectly cites to 42 U.S.C. §19395dd(a).

7 The final judgment of the trial court contains the following unequivocal “finality”

language: 

[T]he Defendants’ No-Evidence Motion for Summary Judgment should be

GRANTED as to all claims and causes of action by Plaintiff against the 

Defendants and that said claims and causes of action pled against the Defendants 

are hereby DISMISSED WITH PREJUDICE. IT IS FURTHER ORDERED, 

ADJUDGED AND DECREED by the Court that Plaintiff take nothing by this suit 

for his claims and causes of action against the Defendants.

See Lehmann v. Har-Con Corp., 39 S.W.3d 191, 192–93, 200 (Tex. 2001) (“[A] judgment issued 

without a conventional trial is final for purposes of appeal if and only if either it actually 

disposes of all claims and parties then before the court, regardless of its language, or it states 

with unmistakable clarity that it is a final judgment as to all claims and all parties[.]”).
6

A. Applicable law

To prevail on a claim for medical negligence, a plaintiff is required to prove 

“(1) a duty by the healthcare provider to act according to a certain standard, (2) a 

breach of the applicable standard of care, (3) an injury, and (4) a sufficient causal 

connection between the breach of care and the injury.” Dunnick v. Marsillo, 654 

S.W.3d 224, 228 (Tex. App.—Austin 2022, pet. granted); see Tex. Civ. Prac. & 

Rem. Code Ann. § 74.004(a)(13); see also Windrum v. Kareh, 581 S.W.3d 761, 

768 (Tex. 2019) (“To prevail in a wrongful-death suit alleging medical

malpractice, a plaintiff must establish the elements of negligence.”).

A claimant bringing a medical-negligence claim must serve each defendant 

against whom a liability claim is asserted with one or more expert reports. See Tex. 

Civ. Prac. & Rem. Code § 74.351(a). The expert must explain the basis of his 

statements to link his conclusions to the facts. See Columbia Valley Healthcare 

Sys., L.P. v. Zamarripa, 526 S.W.3d 453, 460 (Tex. 2017); HMIH Cedar Crest, 

LLC v. Buentello, No. 03-20-00377-CV, 2022 WL 627226, at *6 (Tex. App.—

Austin Mar. 4, 2022, no pet.). 

B. Standard of review

Although the defendants filed a combined traditional and no-evidence 

summary judgment motion, the trial court granted only the no-evidence motion. 

Therefore, we consider only the standards applicable to no-evidence motions.

A no-evidence summary judgment is essentially a pretrial directed verdict, 

and we apply the same legal sufficiency standard in reviewing a no-evidence 

summary judgment as we apply in reviewing a directed verdict. King Ranch, Inc. v. 

Chapman, 118 S.W.3d 742, 750–51 (Tex. 2003). “After adequate time for 

discovery, a party without presenting summary judgment evidence may move for 
7

summary judgment on the ground that there is no evidence of one or more essential 

elements of a claim or defense on which the [nonmovant] would have the burden 

of proof at trial.” Tex. R. Civ. P. 166a(i). Once the motion is filed, the burden 

shifts to the nonmovant to produce summary-judgment evidence raising a genuine 

issue of material fact on the challenged element. See B.C. v. Steak N Shake 

Operations, Inc., 598 S.W.3d 256, 259 (Tex. 2020). A trial court properly grants a 

no-evidence summary-judgment motion if the nonmovant produces no more than a

scintilla of probative evidence—that is, if the nonmovant’s evidence does not rise 

to a level that would enable reasonable and fair-minded people to differ in their 

conclusions. Dallas Morning News, Inc. v. Tatum, 554 S.W.3d 614, 625 (Tex. 

2018).

C. The expert report

Plaintiff produced an expert report from Dr. Van Boven, dated March 27, 

2019, describing how defendants deviated from the appropriate standard of care by 

not properly screening and examining McVaney. These failures resulted in the 

hospital’s failure to appropriately diagnose McVaney and provide the necessary 

and standard treatment for GBS. Dr. Van Boven opined that these violations in the 

standard of care had a “significant deleterious effect [on] the patient’s long-term 

outcome.”

Specifically addressing causation, Dr. Van Boven explains that the hospital

greatly increased McVaney’s chances for a poor outcome by delaying the 

administration of immunotherapy:

Weakness at hospital admission has been recently found to be a main 

predictor of long-term outcomes in patients with GBS. In the largest 

study of its kind of prognostic indicators, nearly 400 patients with 

GBS followed prospectively, Walgaard et al. found that weakness at 

hospital admission, as measured and quantified by the Medical
8

Research Council (“MRC”) sumscore, is a major predictor of poor 

prognosis, i.e. being unable to walk independently, at 4 weeks and 6 

months, the latter being a time-frame wherein a plateau in recovery 

may reasonably be expected.

These data are of relevance to the case of Mr. McVaney. His risk of 

poor outcome was predicted to have more than doubled by the delay 

in treatment caused by [the hospital’s] violations in the standard of 

care. Comparison of his MRC sumscore at initial hospital presentation 

at Baylor Scott & White-Lakeway versus his sumscore upon 

admission at Seton Main not only boded poorly, but has been brought 

to fruition.

More than one year after the delayed diagnosis and delayed treatment 

of GBS, Mr. McVaney remains wheel-chair or walker dependent. The 

consequences of failure to timely treat GBS parallels the sequela of 

failure to treat other acute, monophasic attacks, e.g. stroke, traumatic 

brain injury, or heart attacks. []

Based on these and previous studies, I maintain that the delay in acute

treatment (IV Immunoglobulin) for GBS resultant from Defendants’ 

breaches in the standards of care contributed significantly and 

negatively to Mr. McVaney’s long-term outcome.8

In his report, Dr. Van Boven cites three medical journal articles, two of 

which were included with his expert report. Although Dr. Van Boven 

supplemented his expert report, his opinion on causation and the basis for his 

opinion remained unchanged.

D. The trial court’s judgment

The defendants’ summary-judgment motion discusses the standards for 

admissibility of evidence under Rule 702 and asks the trial court to exclude Dr. 

Van Boven’s opinion because his opinions are not reliable and inadmissible for 

establishing causation.

9 The defendants also filed, on the same day, a

8 The footnotes in Dr. Van Boven’s report have been omitted.

9 The record before this court does not reflect that any Daubert/Robinson motions to 

exclude were filed or considered by the trial court. See E.I. du Pont de Nemours & Co., Inc. v. 
9

Daubert/Robinson motion to exclude the opinion of Dr. Van Boven. See E.I. du 

Pont de Nemours & Co., Inc. v. Robinson, 923 S.W.2d 549, 558 (Tex. 1995) (trial 

court determines whether expert’s opinion is based on reliable methods and

research).

The trial court reviewed Dr. Van Boven’s opinions by performing its own 

analysis of the medical literature relied on by Dr. Van Boven.10, 11 Ultimately, the 

trial court concluded that McVaney did not provide evidence that the delay in 

treatment contributed to his injuries. Although the trial court’s judgment appears to

encompass both a summary-judgment analysis as well as a Rule 702 analysis, the 

trial court never made a ruling in the record excluding or striking the opinions of 

Dr. Van Boven.

This court has previously concluded that a similar ruling from a trial court 

constituted an implied ruling. See Praytor v. Ford Motor Co., 97 S.W.3d 237, 242 

(Tex. App.—Houston [14th Dist.] 2002, no pet.) (“The trial court, in holding that 

[plaintiff] had failed to present ‘legally competent evidence,’ effectively concluded 

that the expert testimony was either inadmissible or insufficient.”). The Austin 

Court of Appeals has also held that a no-evidence summary judgment is proper if 

the only evidence offered by the nonmovant to prove an essential element of the 

claim cannot be given weight by the court. See Jacob v. Int’l Cellulose Corp., Inc., 

Robinson, 923 S.W.2d 549, 558 (Tex. 1995) (trial court determines whether expert’s opinion is 

based on reliable methods and research).

10 While judges act as gatekeepers in determining the admissibility of evidence, judges 

are not scientists or doctors and do not decide whether an opinion is correct. See Gammill v. Jack 

Williams Chevrolet, Inc., 972 S.W.2d 713, 728 (Tex. 1998) (“The trial court is not to determine 

whether an expert’s conclusions are correct, but only whether the analysis used to reach them is 

reliable.”).

11 The trial court’s final judgment is six pages long and is in effect a four-page opinion 

combined with a two-page judgment. For purposes of our review, we only consider the portion 

of the writing that constitutes the judgment.
10

No. 03-06-00210-CV, 2007 WL 1237963, at *4 (Tex. App.—Austin Apr. 27, 

2007, no pet.) (citing with approval Praytor, 97 S.W.3d at 240).

Here, the evidence supporting McVaney’s causation argument was an 

affidavit from Dr. Van Boven and Dr. Van Boven’s expert report. Given that the 

trial court concluded that it had not been provided with sufficient evidence that any 

delay in treatment contributed to McVaney’s injuries, the trial court effectively

addressed the competency of the expert opinions.

E. Causation

Proximate cause is an essential element of a medical-negligence claim and 

consists of (1) cause in fact and (2) foreseeability. Windrum, 581 S.W.3d at 777 

(citing Bustamante v. Ponte, 529 S.W.3d 447, 456 (Tex. 2017)). Foreseeability 

requires only that the defendants should have anticipated that their negligent acts

or omissions would create danger or harm for others; it does not require the 

defendants to have actually anticipated the precise manner in which the injury 

would have occurred. Travis v. City of Mesquite, 830 S.W.2d 94, 98 (Tex. 1992). 

To establish cause in fact, the plaintiff must show by a preponderance of the

evidence that the defendant’s negligent conduct “was a substantial factor in 

bringing about the injuries, and without it, the harm would not have occurred.” 

Bustamante, 529 S.W.3d at 456 (citation omitted). Consequently, the plaintiff must 

“adduce evidence of a ‘reasonable medical probability’ or ‘reasonable 

probability’” that the defendant’s negligence caused the plaintiff’s injury—that is, 

it must be “‘more likely than not’ that the ultimate harm or condition resulted from 

such negligence.” Id. (quoting Jelinek v. Casas, 328 S.W.3d 526. 532–33 (Tex. 

2010)).

The progression and treatment of GBS is not within the common knowledge 

and experience of jurors, and therefore requires expert testimony to establish 
11

causation. See JLG Trucking, LLC v. Garza, 466 S.W.3d 157, 162 (Tex. 2015). “A 

conclusory statement of causation is inadequate; instead, the expert must explain 

the basis of his statements and link conclusions to specific facts.” Abshire v. 

Christus Health Se. Tex., 563 S.W.3d 219, 224 (Tex. 2018). In addition, “when the 

facts support several possible conclusions, only some of which establish that the 

defendant’s negligence caused the plaintiff’s injury, the expert must explain to the 

fact finder why those conclusions are superior based on verifiable medical

evidence, not simply the expert’s opinion.” Jelinek, 328 S.W.3d at 536.

The specific causation question in this case is whether the delay in 

immunotherapy treatment due to defendants’ failure to diagnose McVaney’s GBS 

while he was at the hospital caused McVaney’s GBS to progress faster and/or with 

more severity than it would have with more rapid treatment.

F. Did the trial court err?

1. Arguments of the parties

In their no-evidence motion, the defendants argued that Dr. Van Boven’s 

opinions “provide no evidence which establishes proximate cause between any 

alleged negligence attributable to Defendants and the injuries sustained by Plaintiff

and or the compensable damages sought by the Plaintiff.” They also highlight that 

Dr. Van Boven never discussed or explained the medical literature on which he 

relied. Then analyzing the medical literature on which Dr. Van Boven specifically 

bases his opinion, defendants conclude that Dr. Van Boven’s opinion is not reliable 

because the medical literature does not support or corroborate his opinion.

In response, McVaney argued that Dr. Van Boven’s opinion was reliable and 

was based on peer-reviewed medical literature. McVaney countered defendants’

argument that the medical literature did not support Dr. Van Boven’s opinion and 

asserted that it “is naive to assert/assume that because there is not a study showing 
12

the results of treatment delay at exact particular points in time there is no evidence 

of causation when clearly there is evidence that immediate treatment prior to 

deterioration nearly doubled the improved prognosis.” 

2. Dr. Van Boven’s opinions

Dr. Van Boven’s report extensively addresses the hospital’s breach of the 

standard of care, which was not challenged by the hospital on summary judgment.

With respect to causation, Dr. Van Boven ultimately concludes in his report that 

“the delay in acute treatment (IV Immunoglobulin) for GBS resultant from 

Defendants’ breaches in the standards of care contributed significantly and 

negatively to Mr. McVaney’s long-term outcome.” However, an expert must 

explain the basis of his statements and link his conclusions to specific facts. See

Abshire, 563 S.W.3d at 224.

Dr. Van Boven begins his causation discussion by stating that weakness at 

hospital admission, “as measured and quantified by the Medical Research Council 

(“MRC”) sumscore,” is found to be a main predictor of poor prognosis.

12 Dr. Van 

Boven never provided McVaney’s sumscore at the time of his admission to the 

hospital, nor does he discuss McVaney’s sumscore at any later point in time. Dr. 

Van Boven’s expert report offers no insight into how a sumscore is calculated or

whether or when it was calculated for McVaney. It is also unknown whether 

McVaney’s sumscore was calculated by his medical providers and contained 

within his medical records or whether it is a measure calculated after the fact.

In his affidavit, Dr. Van Boven quantifies the delay in treatment as “nearly 

12 hours delay.” But, despite this case turning on a delay in medical treatment, Dr. 

12 The quote is attributed to a Dutch study heavily relied on by Dr. Van Boven. See C. 

Walgaard, H.F. Lingsma, L. Ruts, P.A. van Doorn, E.W. Steyerberg & B.C. Jacobs, Early 

Recognition of Poor Prognosis In Guillain-Barré Syndrome, NEUROLOGY, 76:968-975 (2011).
13

Van Boven offered no opinion or discussion regarding the appropriate window of 

opportunity for treatment, consistent with the standard of care, in which GBS 

should have been diagnosed to avoid more serious illness. Instead, Dr. Van Boven 

cited to a study that followed 400 patients with GBS and concluded that weakness 

at hospital admission is a major predictor of poor prognosis. It is undisputed that 

when McVaney presented to the hospital he was already experiencing weakness, 

difficulty walking, and tingling in his extremities. Although the record makes clear 

that McVaney’s condition worsened throughout the day, Dr. Van Boven’s report 

and affidavit do not discuss whether the research on which he relies establish the 

consequences of a delay in treatment. Rather, his conclusions assume without

explanation that the research in the Walgaard study is applicable to the causation 

issue before us.13

Although Dr. Van Boven attached the journal articles on which he relies to 

his report, Dr. Van Boven does not explain or discuss how he used the research to 

reach his ultimate conclusion. Without delving into the substance of the underlying 

medical literature on which he relies, the factfinder is left with only Dr. Van 

Boven’s ultimate conclusions.

3. Dr. Van Boven’s conclusory statements are not evidence of causation

To support a claim that a delayed diagnosis allowed the patient’s medical 

condition to worsen or disease to progress, an expert must explain how and why 

the facts support this conclusion. For example, in Naderi v. Ratnarajah, a dentist 

failed to diagnose and treat an infected tooth abscess, causing the patient to lose 

part of his lower jaw. 572 S.W.3d 773, 776 (Tex. App.—Houston [14th Dist.] 

2019, no pet.). The expert explained that the abscess was “clearly visible” on a 

13 Dr. Van Boven’s expert report expressly states that his causation opinion is “[b]ased on 

these and previous studies.”
14

radiograph taken at the initial visit, and that the radiograph showed the infection 

from the tooth spreading into the surrounding bone, but the dentist did not extract 

the tooth or prescribe antibiotics. Id. at 775, 776–77. Seven months later, the 

patient additionally suffered from swelling and inflammation inside his mouth, and 

still the dentist took no action. Id. at 775–76. The expert in Naderi supported his 

causation opinion by describing how medical records documented the appearance 

of additional symptoms over time.

By contrast, in Baylor College of Medicine v. Davies, a gynecologist failed

to diagnose and begin treatment for ovarian cancer, which the plaintiff claimed led 

to significant progression of the cancer resulting in a worse prognosis and reduced 

life expectancy. 599 S.W.3d 323, 326–27 (Tex. App.—Houston [14th Dist.] 2020, 

no pet.). However, the initial finding in the laboratory report stated that the 

plaintiff might have a tumor but did not reflect the stage of the tumor. Id. at 330. 

The plaintiff’s expert concluded the tumor, at the time of the first pathology report

was a stage 1 tumor, but offered no explanation of how he reached that conclusion 

based on the information in the pathology report. Id. For these reasons, we held 

that the plaintiff’s expert report was conclusory because it was only supported by 

ipse dixit. Id. at 326.

McVaney cites the supreme court’s opinion in Bustamante v. Ponte as

instructive and controlling because it involved the question of whether an expert’s 

reliance on a specific medical study could be used to determine whether a delay in 

treatment of a retinal disorder caused an infant’s loss of vision. Bustamante, 529 

S.W.3d at 462. McVaney primarily relies on the Bustamante case to rebut the 

defendants’ argument that the underlying medical studies do not support Dr. Van 

Boven’s opinion (i.e., an “analytical gap”). However, the court’s analysis of the 

medical study in Bustamante is not instructive to the question we must answer in 
15

this appeal. While the parties in Bustamante argued over the applicability of a 

certain study to the situation of the infant injured in that case, the causation experts 

in Bustamante relied on multiple studies, and “offered the bases for their 

opinions.” Id. at 459–60, 462. We agree with McVaney that the law does not 

require Dr. Van Boven to rely on more than one study to establish the reliability of 

his opinions. We also agree with McVaney that the law does not require that the 

study relied on by Dr. Van Boven align perfectly with the factual or medical 

situation at issue in the case. But the law does require Dr. Van Boven to give the 

bases for his opinion and explain his opinion. See Bustamante, 529 S.W.3d at 462 

(opinion is conclusory if stated basis for opinion provides no support); Cooper Tire 

& Rubber Co. v. Mendez, 204 S.W.3d 797, 806 (Tex. 2006) (expert opinion is 

“fundamentally unsupported” when only link between expert’s conclusion and 

underlying facts is expert’s “own say-so”).

Opinion testimony that is conclusory or speculative is not relevant evidence, 

because it does not tend to make the existence of a material fact “more or less 

probable.” See Tex. R. Evid. 401. It may be, as McVaney argues in his appellate 

brief, that Dr. Van Boven “logically deduced” his opinion from the findings of the 

Walgaard study. But because Dr. Van Boven never explained how he logically 

deduced his opinion nor did he link his opinion to specific facts, his opinions in 

this case are not competent evidence. See Abshire, 563 S.W.3d at 224; Coastal 

Transp. Co. v. Crown Central Petrol. Corp., 136 S.W.3d 227, 232 (Tex. 2004)

(citations omitted).

We therefore conclude the trial court did not err in granting the defendants’

no-evidence summary judgment motion and overrule McVaney’s sole issue on 

appeal.
16

III. CONCLUSION

We affirm the judgment of the trial court as challenged on appeal.

/s/ Charles A. Spain

Justice

Panel consists of Chief Justice Christopher and Justices Jewell and Spain.