UNITED STATES COURT OF APPEALS FOR VETERANS CLAIMS

No. 15-4458

ERIC J. STEWART, APPELLANT,

V.

ROBERT L. WILKIE,

SECRETARY OF VETERANS AFFAIRS, APPELLEE.

On Appeal from the Board of Veterans' Appeals

(Argued February 13, 20181 Decided December 20, 2018)

Emma L. Peterson, with whom Zachary M. Stolz, both of Providence, Rhode Island, for 

the appellant. Angela Bunnell, of Providence, Rhode Island was on the brief for the appellant.

James L. Heiberg, with whom Leigh A. Bradley, General Counsel; Mary Ann Flynn, Chief

Counsel; and Thomas E. Sullivan, Deputy Chief Counsel, all of Washington, D.C., were on the 

brief for the appellee.

Before DAVIS, Chief Judge, and SCHOELEN and PIETSCH, Judges.

PIETSCH, Judge, filed the opinion of the Court. DAVIS, Chief Judge, filed an opinion 

concurring in part and dissenting in part. SCHOELEN, Judge, filed an opinion concurring in part 

and dissenting in part. 

PIETSCH, Judge: Eric J. Stewart appeals an October 20, 2015, Board of Veterans' Appeals 

(Board) decision that denied his claim for disability compensation benefits under 38 U.S.C. § 1117 

for a medically unexplained chronic multisymptom illness (MUCMI) incurred during the Persian 

Gulf War. Record (R.) at 2-10. Because the Board misapplied the VA regulation governing 

presumptive service connection for MUCMIs and relied on an inadequate medical examination for 

its decision, the Board decision will be vacated and the matter will be remanded to the Board for 

further action. 

 

1 Oral argument was held on February 13, 2018, at Washburn University School of Law in Topeka, Kansas. 

The Court extends its appreciation to the law school for its hospitality.
2

I. RELEVANT FACTS AND PROCEDURAL HISTORY

Mr. Stewart served on active duty in the U.S. Army from December 2003 until 

February 2005, including service in Southwest Asia from February 2004 to January 2005. During 

his service in Iraq, Mr. Stewart was surrounded by "burn pits"

2 and exposed to smoke from burning 

garbage and to sand and dust. R. at 54.

In December 2005, Mr. Stewart was treated for and diagnosed with asthma. R. at 54. A 

January 2006 pulmonary function test revealed that he had obstructive and restrictive pulmonary 

disease. He filed a claim for disability compensation benefits for asthma in October 2008. R. at 

497. In August 2011, Mr. Stewart's private nurse informed VA that Mr. Stewart had a combined 

obstructive and restrictive pulmonary disease with no known etiology. R. at 220. In December 

2013, the Board denied Mr. Stewart's claim. R. at 147-56. 

Mr. Stewart appealed the decision to this Court, and, in September 2014, the Court granted 

the parties' joint motion to vacate the Board decision and remand the matter to the Board for further 

proceedings. R. at 141-46. The parties concluded that the provisions of 38 C.F.R. § 3.317 

pertaining to presumptive service connection for veterans who served in Southwest Asia were 

"potentially applicable" to Mr. Stewart's claim. Id. The parties agreed that the Board had failed to 

consider "whether [Mr. Stewart's] asthma or combined obstructive and restricted pulmonary 

disease, constituted a [MUCMI]." R. at 144. In December 2014, the Board remanded Mr. Stewart's 

claim to the RO to obtain an "appropriate VA examination to determine the nature and etiology of 

any undiagnosed illness or respiratory infection." R. at 125.

In February 2015, Mr. Stewart underwent a VA examination, at which the examiner noted

that there were prior diagnoses of asthma dating back to 2005. R. at 54-59. The VA examiner 

opined that 2015 pulmonary function tests were consistent with a diagnosis of asthma. Id. The 

examiner diagnosed Mr. Stewart with asthma and stated that he did not have multiple respiratory 

conditions. R. at 56. The VA examiner, relying on medical literature, discussed the nature of 

asthma, noting that it is a chronic lung disease involving inflammation and narrowing of the 

airways of the upper and lower respiratory system, with recurrent periods of wheezing, chest 

 

2 A burn pit refers to an area in military sites devoted to the open-air combustion of refuse, which in Iraq and 

Afghanistan included plastics, batteries, appliances, medicine, dead animals, human feces, and body parts, with jet 

fuel being used as an accelerant. The resultant pollutants included dioxins, particulate matter, polycyclic aromatic 

hydrocarbons, volatile organic compounds, carbon monoxide, hexachlorobenzene, and ash. 

https//en.wikipedia.org/Burn_pit (last visited Sept. 28, 2018).
3

tightness, shortness of breath, and coughing. Id. The examiner explained that people with asthma 

have inflamed airways that react "strongly to certain inhaled substances." Id. Further, she reported 

that asthma attacks may be triggered by exposure to substances including allergens such as dust, 

animal fur, mold, pollen, trees, air pollution, certain medicines, and certain chemicals. Id. The 

examiner opined that Mr. Stewart had no chronic respiratory illness caused by or as the result of 

service. R. at 58. Additionally, the examiner stated that it was less likely than not that Mr. Stewart 

had a MUCMI. R. at 59.

On October 20, 2015, the Board denied Mr. Stewart's claim. In doing so, the Board 

concluded that asthma was not a MUCMI. R. at 8. The Board reasoned that, because the etiology 

of asthma is "'partially understood,'" it could not be considered a MUCMI. Id.

II. ANALYSIS

A. Definition of a MUCMI

In reviewing the Secretary's regulation and its consistency with the statute, "the first inquiry 

is whether the applicable statute provides a clear statement of congressional intent on point." Sears 

v. Principi, 349 F.3d 1326, 1328 (Fed. Cir. 2003). The Supreme Court has stated:

If the intent of Congress is clear, that is the end of the matter; for the court, as well 

as the agency, must give effect to the unambiguously expressed intent of Congress 

. . . . [I]f the statute is silent or ambiguous with respect to the specific issue, the 

question for the court is whether the agency's answer is based on a permissible 

construction of the statute.

Chevron U.S.A., Inc. v. Natural Res. Def. Counsel, Inc., 467 U.S. 837, 842-43 (1984).

Section 1117 of title 38 of the U.S. Code provides presumptive service connection to 

Persian Gulf War veterans who suffer from a "qualifying chronic disability." The statute states that 

a "qualifying chronic disability" may result from (a) an undiagnosed illness; (b) a MUCMI "(such 

as chronic fatigue syndrome, fibromyalgia and irritable bowel syndrome) that is defined by a 

cluster of signs and symptoms"; or (c) any diagnosed illness that the Secretary determines by 

regulation warrants a presumption of service connection. 

The part of section 1117 regarding what constitutes a MUCMI is plain, and the ordinary 

meaning of the words can be used to conclude that a MUCMI is a medically unexplained chronic 

illness. Thus, the Court finds this language clear and unambiguous. However, Congress did not 

define what it means for an illness to be "medically unexplained." Instead, Congress delegated 
4

authority to the Secretary to prescribe regulations to carry out the statute. Specifically, section (d), 

provides that

(1) The Secretary shall prescribe regulations to carry out this section.

(2) Those regulations shall include the following:

(A) A description of the period and geographical area or areas of 

military service in connection with which compensation under this 

section may be paid.

(B) A description of the illnesses for which compensation under this 

section may be paid.

(C) A description of any relevant medical characteristic (such as a 

latency period) associated with each such illness. 

38 U.S.C. § 1117(d).3

At issue in this case is 38 C.F.R. § 3.317(a)(2)(ii), which VA implemented to carry out 

section 1117. This regulation represents VA's attempt to fill a gap left by the statute, which 

provides no definition for the phrase "medically unexplained." When an agency fills a gap left by 

the statute, "courts may not disturb an agency rule unless it is 'arbitrary or capricious in substance, 

or manifestly contrary to the statute.'" Jernigan v. Shinseki, 25 Vet.App. 220, 225 (2012) (quoting 

Mayo Foundation for Medical Educ. & Research v. U.S., 562 U.S. 44, 52 (2011)). Instead, "courts 

will defer to an agency's 'reasonable interpretation of the statute.'" Id. (quoting Gallegos v. 

Principi, 283 F.3d 1309, 1312 (Fed. Cir. 2002). That regulation states:

the term MUCMI is a diagnosed illness without conclusive pathophysiology or 

etiology, that is characterized by overlapping symptoms and signs and has features 

such as fatigue, pain, disability out of proportion to physical findings, and 

inconsistent demonstration of laboratory abnormalities. Chronic multisymptom 

illnesses of partially understood etiology and pathophysiology, such as diabetes and 

multiple sclerosis, will not be considered medically unexplained.

38 C.F.R. § 3.317(a)(2)(ii) (2018).4

It is clear that the regulation seeks to define the undefined statutory phrase "medically 

unexplained." To that end, VA has decided that "pathophysiology" and "etiology" are decisive 

factors in determining whether an illness is "medically unexplained."5 The parties offer different 

 

3 Additionally, 38 U.S.C. § 501(a) provides VA with the "authority to prescribe rules and regulations that are 

necessary or appropriate to carry out the laws administered by the Department [of Veteran Affairs] and are consistent 

with those laws."

4 Both statute and regulation identify signs or symptoms involving the respiratory system as possible 

manifestations of a MUCMI. 38 U.S.C. § 1117(g)(8); 38 C.F.R. § 3.317(b)(8).

5

"Pathophysiology" is defined as "the physiology of abnormal states; spec[ifically]: the functional changes 

that accompany a particular syndrome or disease." WEBSTER'S THIRD NEW INTERNATIONAL DICTIONARY OF THE 
5

interpretations of this regulatory provision. Mr. Stewart contends that a MUCMI is a diagnosed 

illness that lacks either a conclusive pathophysiology or a conclusive etiology. Appellant's 

Response (Res.) to Court's January 2017 Order at 5-11. Thus, Mr. Stewart also contends that a 

chronic multisymptom illness is not considered a MUCMI when the illness has both a partially 

understood etiology and pathophysiology. Appellant's Res. at 5-11. On the other hand, the 

Secretary contends that a MUCMI is a diagnosed illness that lacks both a conclusive 

pathophysiology and a conclusive etiology. Secretary's Res. at 12-16. By contrast, the Secretary 

argues that a chronic multisymptom illness is not a MUCMI when there is either a partially 

understood etiology or a partially understood pathophysiology. Secretary's Res. at 12-16.6

The parties' dispute comes down to the proper interpretation of § 3.317(a)(2)(ii). The Court 

reviews the interpretation of regulations de novo. See Tropf v. Nicholson, 20 Vet.App. 317, 320 

(2006) The Court begins by examining the language of the regulation. Good Samaritan Hosp. v. 

Shalala, 508 U.S. 402, 409 (1993) ("The starting point in interpreting a statute [or regulation] is 

its language."); Goodman v. Shulkin, 870 F.3d 1383, 1386 (Fed. Cir. 2017) (stating that the rules 

of statutory construction apply to interpretation of regulations); Petitti v. McDonald, 27 Vet.App. 

415, 422 (2015) ("Regulatory interpretation begins with the language of the regulation, the plain 

meaning of which is derived from its text and its structure."). If the plain meaning of the regulation 

is clear from its language, then that meaning controls and "that is 'the end of the matter.'" Tropf,

20 Vet.App. at 320 (quoting Brown v. Gardner, 513 U.S. 115, 120, (1994)). If, however, the 

language is ambiguous, then the Court must defer to the agency's interpretation of its regulation 

unless that interpretation is inconsistent with the language of the regulation, is otherwise plainly 

erroneous, or does not represent the agency's considered view on the matter. See Auer v. Robbins, 

519 U.S. 452, 461-62 (1997).

The regulation is structured so that the first sentence sets forth the characteristics that 

identify an illness as a MUCMI. Conversely, the second sentence of the regulation announces the 

 

ENGLISH LANGUAGE UNABRIDGED 1655 (1966) (hereinafter Webster's). "Etiology" means "a science or doctrine of 

causation or of the determination of causes." Id. at 782. In the context of illnesses specifically, "etiology" is defined 

as "all of the factors that contribute to the occurrence of a disease or abnormal condition." Id.

6 We note that Chief Judge Davis's dissent finds that the regulation conflicts with the statute because of its 

use of the phrase "partially understood etiology and physiology." However, neither party argued this in their briefs 

and when asked at oral argument whether the regulation was inconsistent with the statute, the appellant made clear 

that he took the position that the regulation was consistent with the statute. Oral Argument Recording at 4:33-6:33, 

7:04-8:44.
6

characteristics that prevent an illness from being a MUCMI. A fundamental canon of regulatory 

construction is that when interpreting a regulation, the words of the regulation are given "their 

ordinary, contemporary, common meaning," absent an indication that the words "bear some 

different import." Williams v. Taylor, 529 U.S. 420, 431, 435 (2000); Perrin v. United States, 

444 U.S. 37, 42 (1979) (stating that "words [in a regulation], unless otherwise defined, will be 

interpreted as taking their ordinary, contemporary, common meaning").

The first sentence of the regulation describes the characteristics of a MUCMI: "a diagnosed 

illness without conclusive pathophysiology or etiology." The term "conclusive," modifying 

"pathophysiology" and "etiology," is defined as "putting an end to a debate or question especially 

by reason of irrefutability: involving a conclusion or decision: decisive, final." WEBSTER'S at 471.

The words "etiology" and "pathophysiology" are joined by the conjunction "or," which is a 

"function word to indicate . . . an alternative between different or unlike things, states, or actions."

Id. at 80; see Drosky v. Brown, 10 Vet.App. 251, 255 (1997) (holding that the "use of the word 'or' 

provides for an independent basis rather than an additional requirement"). Thus, the Court 

concludes that the plain meaning of the first sentence in the subsection is that a multisymptom 

illness is a MUCMI if either the etiology or the pathophysiology of the illness is inconclusive. 

The second sentence of the subsection states that a multisymptom illness is not a MUCMI 

when it has a partially understood etiology and pathophysiology. "Partially" means "to some 

extent: partly." WEBSTER'S at 1646. The ordinary meaning of "partially" denotes something that is 

incomplete, affecting a part rather than a whole of something. Id. The words "etiology" and 

"pathophysiology" are joined by the conjunctive word "and," meaning that a MUCMI does not 

exist when both the etiology and pathophysiology are partially, but not totally, understood. See

Middleton v. Shinseki, 727 F.3d 1172, 1178 (Fed. Cir. 2013) (stating that use of the conjunctive 

"'and' means that a veteran must satisfy three elements to obtain a 40% disability rating).

Accordingly, the plain meaning of the second sentence is that a multisymptom illness is not a 

MUCMI if both the etiology and the pathology of the illness are partly understood. 

For the Secretary's argument to be correct, the word "or" in the first sentence would have 

to be read as the conjunctive "and." At the same time, the word "and" in the second sentence would 

have to be read as the disjunctive "or." Such a strained construction is clearly at odds with the plain 

reading of the regulation. Additionally, the Court observes that the regulation virtually adopts the 

language used by Congress in the legislative history accompanying the law. Congress explained 
7

that its purpose in including MUCMIs as presumptive conditions was to insure "eligibility for 

chronically disabled Gulf War veterans notwithstanding a diagnostic label by a clinician in the 

absence of conclusive pathophysiology or etiology." 147 CONG. REC. S13,227, 13,238 (daily ed. 

Dec. 13, 2001) (Joint Explanatory Statement) (emphasis added). Congress continued that "it did 

not intend for chronic multisymptom illnesses of partially understood etiology and

pathophysiology" to qualify as MUCMIs. Id. (emphasis added). It is noteworthy that the regulation 

uses the conjunction "or" and the conjunction "and" in the same manner as Congress did in the 

legislative history. Thus, for the Secretary's argument to prevail, the Court would have to ignore 

both the plain language of the regulation and the intent of Congress. 

Applying the plain meaning of § 3.317(a)(2)(ii) to this case, Mr. Stewart is correct that the 

Board misapplied the regulation. Under the proper interpretation of the law, an illness is a MUCMI 

where either the etiology or pathophysiology of the illness is inconclusive. Conversely, a 

multisymptom illness is not a MUCMI where both the etiology and the pathophysiology of the 

illness are partially understood. Here, the Board concluded that Mr. Stewart's asthma was not a 

MUCMI because asthma has a "partially understood etiology." R. at 8. The Board did not make a 

finding that the pathophysiology of asthma was also "partially understood," as it was required to

do under the law. 38 C.F.R. § 3.317(a)(2)(ii). 

B. The Specific Etiology of a Veteran's Disease

The next issue raised by Mr. Stewart also involves the proper interpretation of

§ 3.317(a)(2)(ii). He argues that if the etiology of his individual asthma is unknown, it may qualify 

as a MUCMI, even though the etiology of asthma as it generally affects the public has a partially 

understood etiology or pathophysiology. Appellant's Brief (Br.) at 7-9; Appellant's Res. to Court's 

January 2017 Order at 11-15; Appellant's Res. to Court's October 2017 Order at 5-6. In response, 

the Secretary contends that "etiology" as used in this subsection refers to the cause of the diagnosed 

illness generally, rather than a specific etiological cause pertaining to an individual veteran.

Secretary's Br. at 7-8. Essentially, the parties disagree on whether the term "medically 

unexplained" requires VA to identify the cause of a specific veteran's illness or whether the 

question may be resolved by general knowledge in the medical community about the illness. 

The U.S. Court of Appeals for the Federal Circuit addressed a similar legal question in 

Goodman. In that case, Mr. Goodman was seeking presumptive service connection for rheumatoid 

arthritis (RA) as a MUCMI. Goodman, 870 F.3d at 1384. In denying his claim, the Board relied 
8

on an advisory medical opinion concluding that RA was not a MUCMI because the etiology and 

pathophysiology of RA were partially understood. This Court affirmed the Board decision. In his 

appeal to the Federal Circuit, Mr. Goodman argued that this Court misinterpreted § 3.317. He 

argued that, by allowing the Board to rely on a medical expert opinion that concluded that RA had 

a partially understood etiology and pathophysiology, the Court effectively allowed the VA medical 

expert to establish a general rule that was binding in future claims that RA is not a MUCMI. Id. at 

1386. 

The Federal Circuit noted that § 3.317 did not "prohibit medical professionals from 

professing whether certain medical diseases may constitute a MUCMI." Id. at 1387. Further, the 

Federal Circuit observed that VA's published guidance granted VA adjudicators "'the authority to 

determine on a case-by-case basis whether additional diseases meet the criteria'" for a MUCMI 

"'in the same manner as they make other determinations necessary to decide claims.'" Id. (quoting 

and adding emphasis to 75 Fed. Reg. 61,995, 61,995 (October 7, 2010)). The Federal Circuit held 

that "the VA adjudicator may consider evidence of medical expert opinions and all other facts of 

record to make the final determination of whether a claimant has proven, based on the claimant's 

unique symptoms, the existence of a MUCMI stated." Id. at 1388 (emphasis added).

The Court concludes that the determination of whether an illness is "medically 

unexplained" is particular to the claimant in each case. In Goodman, the Federal Circuit repeatedly 

stated that a MUCMI determination was to be based on a claimant's unique symptoms and the 

evidence of record. Id. This approach is consistent with this Court's long-standing treatment of 

medical evidence and treatise evidence in service-connection claims. The Court has held that 

generic information in a medical journal or treatise that certain factors could cause a medical 

condition does not, as a general matter, establish nexus absent additional evidence that those 

factors did cause a veteran's condition. See Sacks v. West, 11 Vet.App. 314, 317 (1998); see also 

Libertine v. Brown, 9 Vet.App. 521, 523 (1996); Beausoleil v. Brown, 8 Vet.App. 459, 463 (1996).

If an illness could, as a general matter, be excluded from being a MUCMI on the basis of 

definitional materials or treatises, there would be no necessity of examining all the facts of record 

and the claimant's unique symptoms. The Secretary has acknowledged that "[t]he issue of whether 

a Veteran’s particular chronic multisymptom disability pattern is without a conclusive etiology . . 

. must be determined on a case-by case basis and will require a medical opinion." VA Training 

Letter 10-01 at 5 (emphasis added). Treatise evidence suffices to establish nexus only where 
9

“standing alone, [it] discusses generic relationships with a degree of certainty such that, under the 

facts of a specific case, there is at least plausible causality based upon objective facts . . . .” Wallin 

v. West, 11 Vet.App. 509, 514 (1998). Thus, if definitional or treatise evidence were sufficient to 

conclusively identify the cause of a claimed illness, that is, with the requisite degree of certainty, 

the illness would not be medically unexplained. Any lesser degree of certainty would require 

evaluation of the unique facts of the veteran's situation to determine if his or her illness is medically 

unexplained.

Having found that a determination of whether a condition is a MUCMI must be based on 

an individual veteran's circumstances, we now turn to whether the evidence was adequate to decide 

Mr. Stewart's claim. 

C. Adequacy of Medical Examination

A medical examination is considered adequate "where it is based upon consideration of the 

veteran's prior medical history and examinations and describes the disability, if any, in sufficient 

detail so that the Board's 'evaluation of the claimed disability will be a fully informed one.'" Stefl

v. Nicholson, 21 Vet.App. 120, 123 (2007) (quoting Ardison v. Brown, 6 Vet.App. 405, 407 

(1994)). The opinion must "support its conclusion with an analysis that the Board can consider and 

weigh against contrary opinions." Id. at 124-25. This Court has held that "most of the probative 

value of a medical opinion comes from its reasoning" and that a medical examination or opinion 

"is [not] entitled to any weight . . . if it contains only data and conclusions." Nieves-Rodriguez 

v. Peake, 22 Vet.App. 295, 304 (2008). "Whether a medical opinion is adequate is a finding of 

fact, which this Court reviews under the 'clearly erroneous' standard." D'Aries v. Peake, 

22 Vet.App. 97, 104 (2008); see Gilbert v. Derwinski, 1 Vet.App. 49, 52 (1990). A finding of fact 

is clearly erroneous when the Court, after reviewing the entire evidence, "is left with the definite 

and firm conviction that a mistake has been committed." United States v. U.S. Gypsum Co., 333 

U.S. 364, 395 (1948); Gilbert, 1 Vet.App. at 52.

Here, the parties agree, for different reasons, that the 2015 VA examiner's opinion that Mr. 

Stewart's asthma was not a MUCMI is inadequate. The Court agrees. Although the VA examiner 

discussed in great detail the symptoms of asthma and identified the events or substances that may

trigger asthma attacks, she did not address the etiology or pathophysiology of asthma, either partial 

or conclusive. That certain factors may trigger attacks once a person has asthma does not explain 

why that person contracted asthma in the first place. Factors that may trigger attacks have nothing 
10

to do with etiology, which requires an identification of the cause of a condition. Because the VA 

examiner failed to address the etiology or pathophysiology of Mr. Stewart's asthma, we find the 

opinion inadequate. On remand, the Board should obtain a medical opinion that addresses this

question and provides a clear rationale supporting the opinion.

III. CONCLUSION

The Board's October 20, 2015, decision is VACATED and this matter is REMANDED for 

further proceedings consistent with this decision.

DAVIS, Chief Judge: concurring in part and dissenting in part: I fully endorse the analysis 

in Section II.B., and concur in the disposition of this case in Section II.C. I dissent from Section 

II.A., insofar as it may be read to find ambiguity in the phrase "medically unexplained," leading 

to a conclusion that the Secretary's regulation is valid. As described below, the regulation, 38 

C.F.R. § 3.317(a)(2)(ii), setting forth the Secretary's definition of a medically unexplained chronic 

multisymptom illness (MUCMI), is inconsistent with the plain meaning of the statute and is 

arbitrary and capricious, and otherwise contrary to the statute.7 Therefore, the regulation operates 

in a manner that inappropriately excludes potential medically unexplained multisymptom illnesses 

from coverage. We should declare it invalid.

The majority suggests that my concerns with the validity of the regulation are not raised 

by the briefing, and further note a statement at oral argument that the regulation was consistent 

with the statute.8 The majority does not mention the supplemental briefing questions issued by the 

Court, which included the following two questions:

1. Is the language of 38 U.S.C. § 1117 ambiguous? 

2. If so, should the Court accept the Secretary’s interpretation of the statute, and how much 

deference is owed to the Secretary’s interpretation?

I believe my concerns with the validity of this regulation are within the scope of these questions 

and the responses thereto. Indeed, it was those questions that seeded my consideration of the 

validity of the regulation. Moreover, the appellant's statement at oral argument, even assuming it 

was a well-considered position, is hardly a reason to ignore the severe defects in this regulation as 

 

7 See Cox v. McDonald, 28 Vet.App. 318, 324 (2018) (after determining that a statute is silent or ambiguous 

with respect to an issue, the Court must determine whether the Secretary's regulation is arbitrary, capricious, or 

manifestly contrary to the statute).

8 See supra at 5, note 6. 
11

described below. "When an issue or claim is properly before the Court, the Court is not limited to 

the particular legal theories advanced by the parties, but rather retains the independent power to 

identify and apply the proper construction of governing laws."9

Furthermore, the majority's view of the record should lead to a decision to refrain from 

consideration of the validity of the regulation. Instead, the majority goes out of its way to attempt 

to add the imprimatur of the Court to the regulation in question. I therefore regard the discussion 

of the majority opinion regarding the validity of the regulation as dicta, that is, not required for the 

disposition of the appeal as characterized by the majority's view of the record. 

The Court's supplemental briefing questions raise the threshold issue of the regulation's 

conformity with the statute. The interpretation of a statute is a question of law that the Court 

reviews de novo.10

In the regulatory context, however, the Court may not disturb an agency rule unless it is 

"'arbitrary or capricious in substance, or manifestly contrary to the statute.'"11

When a court reviews an agency's construction of a statute which it administers, it 

is confronted with two questions. First, always, is the question whether Congress 

has directly spoken to the precise question at issue. If the intent of Congress is clear, 

that is the end of the matter; for the Court as well as the agency must give effect to 

the unambiguously expressed intent of Congress.12 

"[I]f the statute is silent or ambiguous with respect to the specific issue," however, "the question 

for the Court is whether the agency's answer is based on a permissible construction of the statute."13

Conversely, "no deference is due to agency interpretations at odds with the plain language of the 

statute itself. Even contemporaneous and longstanding agency interpretations must fall to the 

extent they conflict with statutory language."14 The Court must employ the standard tools of 

 

9 Kamen v. Kemper Fin. Services, Inc., 500 U.S. 90, 99 (1991); see also Tatum v. Shinseki, 24 Vet.App. 139, 

144 (2010) (parties' agreement at oral argument cannot bind the Court); Rykus v. Brown, 6 Vet.App. 354, 359 (1993) 

("The Court is not bound by the Secretary's concessions . . . . ").

10 Cook v. Snyder, 28 Vet.App. 330, 338 (2017).

11 Household Credit Services, Inc. v. Pfenning, 541 U.S. 232, 242 (2004) (quoting United States v. Mead 

Corp., 533 U.S. 218, 227 (2001)).

12 Chevron v. Natural Resources Def. Council, 467 U.S. 837, 842 (1984).

13 Id. at 842-43.

14 Public Employees Retirement System of Ohio v. Betts, 492 U.S. 158, 171 (1989).
12

statutory construction, including the canons of statutory interpretation, to determine whether 

Congress has directly addressed the precise question at issue.15

I. The statutory definition of MUCMI is not ambiguous.

The governing statute provides compensation for Persian Gulf veterans having a "chronic 

qualifying disability," which is divided into three classes:

A. An undiagnosed illness

B. A medically unexplained chronic multisymptom illness [MUCMI] (such as chronic 

fatigue syndrome, fibromyalgia, and irritable bowel syndrome) defined by a cluster of 

signs or symptoms

C. Any diagnosed illness that the Secretary determines [by regulation] to warrant a 

presumption of service-connection.

The statutory language for consideration here is: "A medically unexplained chronic multisymptom 

illness [MUCMI] . . . defined by a cluster of signs or symptoms."16

The Secretary asserts that this language contains ambiguity with respect to the phrase 

"medically unexplained,"17 but offers no contextual or linguistic reasons why this is so. "[S]imply 

saying something is ambiguous does not make it so."18

"Ambiguity" is defined as "[a]n uncertainty of meaning or intention, as in a contractual 

term or statutory provision."19 The plainness or ambiguity of statutory language is determined by 

reference to the language itself, the specific context in which that language is used, and the broader 

context of the statute as a whole."20

"Statutory construction must begin with the language employed by Congress and the 

assumption that the ordinary meaning of that language accurately expresses the legislative 

purpose."21 The term "medically unexplained" is defined neither in section 1117 nor in any other 

provision of veterans law. Therefore, the ordinary and accustomed meaning of the term applies.22

 

15 Chevron, 467 U.S. at 843 n9; Cathedral Candle Co. v. USITC, 400 F.3d 1352, 1362 (Fed. Cir. 2005).

16 38 U.S.C. § 1117.

17 Secretary's Response to Supplemental Briefing Order of Jan. 17, 2018, at 8.

18 Johnson v. Shinseki, 28 Vet.App. 237, 254 (2013) (Kasold, C.J., dissenting).

19 BLACK'S LAW DICTIONARY 93 (9th ed. 2009).

20 Robinson v. Shell Oil Co., 519 U.S. 337, 341 (1997).

21 Park 'N Fly, Inc. v. Dollar Park & Fly, Inc., 469 U.S. 189, 194 (1985).

22 Prokarym v. McDonald, 27 Vet.App. 307 (2015).
13

"Medically unexplained" simply means that an illness has not been explained by the current 

knowledge of the medical community. The definition of the word "unexplained" most pertinent to 

the medical context is "not accounted for or attributable to an identified cause: SIDS [sudden 

infant death syndrome] is still an unexplained phenomenon."23 Thus, section 1117(a)(2)(B) refers 

to a chronic multisymptom illness, which the medical community is unable to attribute to an 

identified cause, but characterized by a cluster of signs or symptoms. 

Contrary to the suggestion by the majority, 24 the term "medically unexplained" is not 

undefined and there is no gap for the Secretary to fill. There is nothing in the term "medically 

unexplained" itself, or in the structure of the statute, that would counsel against applying the term 

MUCMI to any chronic multisymptom illness not attributable to an identified cause.

The unambiguity of this plain meaning is confirmed by relevant canons of statutory 

interpretation. First, it is consistent with the general-terms canon.

Without some indication to the contrary, general words (like all words, general or 

not) are to be accorded their full and fair scope. They are not to be arbitrarily 

limited. This [canon] is based on the reality that it is possible and useful to formulate 

categories (e.g., "dangerous weapons") without knowing all the items that may fit 

. . . within those categories.25

The phrase "medically unexplained" is such a general term that is entitled to be applied to the full 

scope of its plain meaning. Second, this plain meaning is supported by the omitted-case canon: a 

matter not covered by the statute is to be treated as not covered.26 This canon includes the corollary 

that a judge, and in this case, the agency, should not derive unprovided-for exceptions to the text. 

"[I]f the Congress [had] intended to provide additional exceptions, it would have done so in clear 

language."27 

Moreover, there is no warrant for construing a snippet of the statutory phrase rather than 

the entire phrase of which it is a part. "In expounding a statute, we must not be guided by a single 

 

23 NEW OXFORD AMERICAN DICTIONARY 1887 (2010) (emphasis added).

24 See supra at 4. 

25 B. GARNER & A. SCALIA, READING LAW: THE INTERPRETATION OF LEGAL TEXTS at 101 [hereinafter 

"Garner & Scalia"]; see, e.g., Slaughter House Cases, 83 U.S. 36, 73 (16 Wall.) (1872) (although the rights of blacks 

were in contemplation of Congress in enacting the 13th, 14th, and 15th Amendments, the word "persons" employed 

in the text of the amendments applied to guarantee to other classes of people the rights protected by those 

amendments).

26 See Garner & Scalia, supra n.25, at 93. 

27 Petteys v. Butler, 367 F.2d 528, 538 (8th Cir. 1966) (Blackmun, J., dissenting).
14

sentence or member of a sentence, but [should] look to the provisions of the whole law, and to its 

object and policy."28 

In this instance the words "medically unexplained" are given a more precise context by 

both the neighboring words and the disease examples given.29 It is clear from the entire phrase 

that the statute defines a class of "qualifying chronic disabilit[ies]" consisting of illnesses as to 

which medical understanding has progressed no further than identifying a cluster of characteristic 

signs and symptoms, and perhaps giving it a name, i.e., a "diagnostic label." There is simply no 

reason for the Secretary to define the statutory language further by regulation.

"Only where a statute's plain meaning leads to an absurd result that Congress clearly never 

could have intended is [the] 'plain meaning rule' abandoned for a review of the applicable 

legislative history and statutory construction." 30 That the plain meaning of "medically 

unexplained" could lead to the inclusion of such illnesses as diabetes and multiple sclerosis as 

MUCMIs might be inadvisable, but not absurd. Diabetes is presumptively service connected with 

respect to herbicide exposure,31 and multiple sclerosis is a chronic disease that is presumptively 

service connected if it manifests within 7 years from the date of separation from service.32 It is 

therefore unclear that Congress—as opposed to some individual legislators—or the President who 

signed the bill could not have intended that these conditions be included in the statutory definition 

of a MUCMI. It is not for the Secretary or the Court to impose such exclusions when the statute 

does not.

II. The Secretary's regulation imposes restrictions that contradict the plain meaning 

of the statute, and the regulation is otherwise inconsistent with the statute.

The implementing VA regulation states:

the term [MUCMI] means a diagnosed illness without conclusive pathophysiology 

or etiology, that is characterized by overlapping symptoms and signs and has 

features such as fatigue, pain, disability out of proportion to physical findings, and 

inconsistent demonstration of laboratory abnormalities. Chronic multisymptom 

 

28 Ortiz-Valles v. McDonald, 28 Vet.App. 65, 70 (2016) (citing United States Nat'l Bank of Oregon v. 

Independent Ins. Agents of Am. Inc., 508 U.S. 439. 455 (1993)). 

29 See Freeman v. Quicken Loans, 566 U.S. 624, 635 (2012).

30 Alleman v. Principi, 16 Vet.App. 253, 255 (2002); Sabonis v. Brown, 6 Vet.App. 426, 430 (1994) (same); 

Mintz v. Brown, 6 Vet.App. 273, 282 (same).

31 38 C.F.R. § 3.309(e) (2018).

32 38 C.F.R. §§ 3.307(a)(3) (2018), 3.309(a). A MUCMI is compensable if it manifested to a degree of 10% 

by December 31, 2016. 38 C.F.R. § 3.317(a)(1)(i) (2018).
15

illnesses of partially understood etiology and pathophysiology, such as diabetes 

and multiple sclerosis, will not be considered medically unexplained. 33

A. The regulation is inconsistent with the plain meaning of the statute.

The concepts of "conclusive pathophysiology or etiology" and "partially understood 

etiology and pathophysiology" appear nowhere in the statute. The Secretary adopted both 

sentences of this regulation from the legislative history.34

In effect, the regulation operates to constrict the plain meaning of "medically unexplained" 

as employed in the statute. The full scope of the statutory term "unexplained" can only be shrunk 

by regulatory concepts of "partially understood etiology and pathophysiology" if one inserts the 

word "completely," or perhaps "predominantly," in front of the unqualified phrase, as the drafters 

of the statute did not. A regulation imposing a requirement not imposed by the enabling statute is 

invalid.35

The restrictions in § 3.317(a)(2)(ii) are fundamentally grounded on a notion that Congress 

would not have intended the term "medically unexplained" to sweep as broadly as the plain 

language requires. "What Congress 'would have wanted' it did not provide, and that is the end of 

the matter."36

B. The regulatory definition of MUCMI is inconsistent with the structure of the 

statute.

"'Statutory terms are interpreted in their context and with a view to their place in the overall 

statutory scheme.'"37 Here, the word "diagnosed" is employed in 38 U.S.C. § 1117(a)(2)(C), and 

its negative in subsection (a)(2)(A), but omitted from subsection (a)(2)(B). "Where Congress 

includes particular language in one section of a statute but omits it in another section of the same 

Act, it is generally presumed that Congress acts intentionally and purposely in the disparate 

inclusion or exclusion."38 Further, if Congress had intended a MUCMI to be a diagnosed condition, 

it would be expected that the wording of subsection (a)(2)(C) would have begun "any other 

 

33 38 C.F.R. § 3.317(a)(2)(ii) (emphasis added).

34 68 Fed. Reg. 34,539, 34,540 (June 10, 2003); 75 Fed. Reg. 61,995, 61,996 (Oct. 7, 2010); see 147 CONG.

REC. S. 13,227, 13,238 (daily ed. Dec. 13, 2001) (Joint Explanatory Statement).

35 See Brown v. Gardner, 513 U.S. 115 (1994).

36 Garner & Scalia, supra n.25 at 94.

37 Halle v. McDonald, 28 Vet.App. 112, 116 (2016) (quoting Tyler v. Cain, 533 U.S. 656, 662 (2001)). 

38 Russello v. U.S., 446 U.S. 16, 23 (1983).
16

diagnosed illness." The conclusion to be drawn is that Congress did not consider a MUCMI as a 

diagnosed condition. 

Yet, the Secretary's regulation, purportedly defining MUCMI, begins with the words "a 

diagnosed condition." It is possible that the Secretary may have meant to invoke the concept of a 

mere "diagnostic label," as referred to in the legislative history. The presumption, however, is that 

a given term bears the same meaning throughout a statute or a regulation.39 Thus, the Court may 

not presume that the meaning of "undiagnosed" and "diagnosed" as used in the wording of the 

statute, and incorporated into the regulation, differs from the meaning of "diagnosed" that the 

Secretary infers to be part of the provision dealing with MUCMI. 

Moreover, the words of a regulation are given their ordinary and accustomed meaning.40 

A "diagnosis" is defined as "determination of the nature of a case of disease."41 This definition 

extends beyond merely giving a name to a condition, but requires an understanding of the nature 

of an illness. 

This inconsistency with the statute has more than semantic implications. Another portion 

of the Secretary's regulation excludes from compensation any disease that can be attributed to a 

"known clinical diagnosis."42 The ordinary meaning of "clinical diagnosis" is a "diagnosis based 

on signs, symptoms, and laboratory findings during life."43 This section of the regulation offers no 

alternative understanding of the term "clinical diagnosis," which, according to the regulation, is to 

be based on "history, physical examination, and laboratory tests."44 The Secretary argued that Mr. 

Stewart's obstructive and restrictive lung condition was excluded from being a MUCMI because 

asthma is a clinical diagnosis, 45 although that argument was undeveloped. 

It is unclear what sort of diagnosis—even the application of a diagnostic label—would not 

be a clinical diagnosis "based on" history, examination, signs, symptoms, and laboratory findings. 

Even the conditions defined by statute as MUCMIs are still identified by a clinical diagnosis, albeit 

 

39 Gardner, 513 U.S. at 118; Voracek v. Nicholson, 421 F.3d 1299, 1304 (Fed. Cir. 2005).

40 Ortiz-Valles, 28 Vet.App. at 69 (and cases cited).

41 DORLAND'S at 507. 

42 38 C.F.R. § 3.317(a)(1)(ii).

43 DORLAND'S at 507.

44 38 C.F.R. § 3.317(a)(1)(ii).

45 Secretary's Brief at 6.
17

on the absence rather than the presence of identifiable factors by which the illness could be 

attributed to any other clinical condition. Chronic fatigue syndrome, for instance, requires, among 

other factors, "the exclusion by history, physical examination, and laboratory tests of all other 

clinical conditions that may produce similar symptoms."46 So chronic fatigue syndrome would still 

arguably be a clinical diagnosis, although it would be classified as a diagnosis of exclusion. 

The sum of this discussion is that just about any illness of interest to Gulf War veterans, 

with the possible exception of those identified by diagnoses of exclusion, would be attributed to a 

known clinical diagnosis. Such a clinical diagnosis to label a veteran's condition would be possible 

long before the medical community identified the cause of the condition, either conclusively or 

partially. During the AIDS crisis, for instance, the detection of reduced immune cells by laboratory 

blood tests, together with the symptoms and signs of the disease, could suffice to label the 

condition (i.e., yield a "clinical diagnosis") even though there was no understanding of the etiology 

of the condition. The etiology of the illness was explained only with the discovery of the Human 

Immunodeficiency Virus. The interaction of the Secretary's definition of a MUCMI as a 

"diagnosed condition" and the provision on "clinical diagnosis" operates such that future analyses 

of MUCMIs, apart from those named in the statute, may well yield the null set. That result is hardly 

in keeping with the legislative goal evident in the revision of the statute to include MUCMIs. 

The "clinical diagnosis" provision has been part of the Secretary's regulation from the 

beginning. It may describe an "undiagnosed illness" and may not conflict with the definition of 

MUCMI if the latter is not required to be a "diagnosed condition" in the ordinary understanding of 

that term. That enigma begs for redrafting of the regulation, which the Court should declare invalid.

III. The Secretary's recourse to the legislative history produced an inherent 

contradiction that renders the regulation arbitrary and capricious.

The only possible reason for introducing the exclusionary concept of "partially understood 

etiology and pathophysiology" in § 3.317 is that it is contained in the legislative history. The Senate 

report stated: "In selecting this [statutory] language it is the intent of the Committee to ensure 

eligibility for chronically disabled Gulf War veterans notwithstanding a diagnostic label by a 

clinician in the absence of conclusive pathophysiology or etiology."47 In the next paragraph, the 

 

46 38 C.F.R. § 4.88a (2018).

47 147 Cong. Rec. S. 13,227, S. 13,238 (daily ed. Dec, 13, 2001) (statement of Sen. Rockefeller) (emphasis 

added).
18

committee report commented on the inclusion of the three illnesses (chronic fatigue syndrome, 

fibromyalgia, and irritable bowel syndromes) as examples of MUCMIs in the statute. The report 

then stated: "The Committees do not [intend] this definition to assert that the cited syndromes can 

be clinically or scientifically linked to Gulf War service based on current evidence, nor do they 

intend to include [MUCMIs] of partially understood etiology and pathophysiology such as 

diabetes or multiple sclerosis."48 The first sentence of § 3.317(a)(2)(ii) corresponds to the first 

quoted remark and the second sentence of the regulation to the second quoted remark. 

There is no need in this case to discuss the legal and doctrinal difficulties with employing 

legislative history in statutory interpretation, 49 or the confusing and contradictory statements 

regarding such usage contained in the caselaw of this Court and its reviewing court.50 Suffice it 

to say that the Secretary's resort to legislative history in this case results in a blatant ambiguity 

rendering § 3.317(a)(2)(ii) unintelligible. 

There is an inherent contradiction in the two sentences of § 3.317(a)(2)(ii), extracted from 

the legislative history. The first sentence of the regulation describes the characteristics of a 

MUCMI: "a diagnosed illness without conclusive pathophysiology or etiology." The term 

"conclusive," modifying "pathophysiology" and "etiology," is defined as "putting an end to a 

debate or question especially by reason of irrefutability: involving a conclusion or decision: 

decisive, final." 51 The second sentence purports to exclude illnesses of "partially understood 

etiology and pathophysiology." But if the etiology and pathophysiology of an illness are only 

 

48 Id. (emphasis added).

49 See Lawson v. FMR LLC, 571 U.S. 429, 459-460 (2014) (Scalia, J., concurring).

50 Compare Wanner v. Principi, 370 F.3d 1124, 1130 (Fed. Cir. 2004) ("[T]he clarity of the legislative scheme 

makes resort to the legislative history unnecessary.") with Glaxo Operations U.K. Ltd. V. Quigg, 894 F.3d 392, 395 

(Fed. Cir. 1990) (legislative history should be examined at least to determine whether there is clearly expressed 

legislative intent contrary to the statutory language). Compare Lee v. West, 13 Vet.App. 388, 395 (2000) ("Because 

the plain meaning of the statute [contradicts] the Secretary's position we need not consider the statute's legislative 

history.") (citing Daily v. Cisneros, 509 U.S. 137 (1993) and Frederick v. Shinseki, 24 Vet.App. 335, 341 (2011), rev'd 

on other grounds 684 F.3d 1263 (Fed. Cir. 2012) ("We start with the axiom that legislative history is not legislation 

and cannot trump the plain meaning of the legislation.") (citing Van Wersch v. Dept. of Health & Human Servs., 197 

F.3d 1144, 1152 (Fed. Cir 1999)) with Atencio v. O'Rourke, 30 Vet.App. 74, 84 (2018) (legislative history should be 

examined to determine whether there is Congressional intent contrary to the plain meaning of the statute). See also 

Cypert v. Peake, 22 Vet.App. 307, 311 (2008) ("[T]he Court cannot read into a statute an alternative purpose premised 

on congressional intent.").

51 WEBSTER'S THIRD NEW INTERNATIONAL DICTIONARY OF THE ENGLISH LANGUAGE UNABRIDGED 471

(1966).
19

partially understood, it follows that the illness is without conclusive pathophysiology or conclusive 

etiology. 

The examples of illnesses named in the regulation, as supposedly of partially understood 

etiology and pathophysiology, are of no help in resolving the ambiguity. As the Secretary argued,52

both multiple sclerosis and diabetes are of unknown or inconclusive etiology, and therefore do not 

have "partially understood etiology and pathophysiology." 53 Although Congress could have 

explicitly excluded these illnesses from the statutory definition of MUCMIs, for whatever reason, 

it did not. More to the point, these illnesses do not clarify how an illness can be of only partially 

understood etiology and pathophysiology yet have conclusive etiology and conclusive 

pathophysiology. 

We are left with a fundamental ambiguity that is not resolved by the incorporation of the 

legislative history remarks into the Secretary's regulation. "[A]mbiguities in the legislative history 

are insufficient to undercut the ordinary understanding of the statutory language."54

The most enthusiastic advocates of the use of legislative history agree that employing an 

inherently ambiguous legislative history to attenuate the plain meaning of statutory language is 

improper. Even where there are "contradictory indications in the statute's legislative history . . . we 

do not resort to legislative history to cloud a statutory text that is clear."55 As Justice Kagan 

recently observed: "Those of us who make use of legislative history believe that clear evidence of 

congressional intent may illuminate ambiguous text. We will not take the opposite tack of allowing 

ambiguous legislative history to muddy clear statutory language."56 "When legislative history does 

not contain 'clear evidence of congressional intent' and is 'more conflicting than the statutory text 

is ambiguous' it is of little use."57 Here, the legislative history is ambiguous at best, and should not 

be employed to detract from the plain meaning of the statute.

 

52 Secretary's Response to Supplemental Briefing Order of Jan. 17, 2018, at 11.

53 See DORLAND'S at 1680 (32d ed. 2012) (etiology of multiple sclerosis is unknown).

54 Ardestani v. INS, 502 U.S. 129, 137 (1991).

55 Ratzlaf v. United States, 510 U.S. 135, 147-48 (1994) (citing Barnhill v. Johnson, 503 U.S. 393, 401 (1992) 

(appeals to legislative history are well taken only to resolve statutory ambiguity)). 

56 National Assoc. of Mfrs. v. Dept. of Defense, 138 S.Ct. 617, 634 n 9 (2018) (citing Milner v. Dept. of Navy, 

502 U.S. 562, 572 (2011)). 

57 Jensen v. Shinseki, 29 Vet.App. 66, 76 n.7 (2017) (quoting Milner). 
20

Thus, any chronic multisymptom illness about which the medical community possesses 

some knowledge, short of a conclusive understanding, is simultaneously within and without the 

MUCMI classification under the Secretary's regulation. The implementation of the regulation 

depends entirely on which sentence is the focus of the analysis, and it is indeterminate how the 

regulation would be applied to any medically unexplained illness other than those named in the 

statute. The word "capricious" means "characterized by or subject to whim."58 Therefore, I believe 

the regulation adopted by the Secretary to implement the statute, § 3.317(a)(2)(ii), is arbitrary and 

capricious in substance. 

IV. There is no evidence on which to conclude that Mr. Stewart's asthma was not 

medically unexplained.

In the decision here on appeal, the Board stated that "asthma may be due to allergic 

manifestations or provoked by factors such as vigorous exercise, irritant particles, or psychological 

stress, among other causes." 59 The Board also cited a VA medical examination report that 

contained the following remarks:

Per literature review, many things can trigger or worsen asthma symptoms. Triggers 

may cause asthma to flare up while directly in contact with a trigger. Triggers may 

include: Allergens from dust, animal fur, cockroaches, mold, and pollens from 

trees, grasses, and flowers; Irritants such as cigarette smoke, air pollution, 

chemicals or dust in the workplace, compounds in home décor products, and sprays 

(such as hairspray); Medicines such as aspirin or other nonsteroidal antiinflammatory drugs and nonselective beta-blockers; Sulfites in foods and drinks; 

Viral upper respiratory infections, such as colds; Physical activity, including 

exercise.60

Invoking the regulatory concept of "partially understood etiology," the Board concluded that 

asthma is not medically unexplained.

"Etiology" is "the study or theory of the factors that cause disease and the method of their 

introduction to the host; the causes or origin of a disease or disorder."61 Neither the medical 

definition of asthma nor the VA examination report furnishes any information as to the etiology 

of asthma, either partial or conclusive. That certain factors may trigger attacks once a person has 

 

58 WEBSTER'S II NEW RIVERSIDE UNIVERSITY DICTIONARY 227 (1984).

59 R. at 8 (citing the 30th edition of DORLAND'S at 168).

60 R. at 59.

61 DORLAND'S at 652.
21

asthma does not explain why that person contracted asthma in the first place. Factors that may 

trigger attacks have nothing to do with etiology, which requires an identification of the cause of a 

condition.

"Some cases [of asthma] are allergic manifestations in sensitized persons (allergic a.)."62

But it is still not clear why certain persons contract asthma and others do not. Not all people with 

allergies have asthma, and not all asthmatics have allergies.63 Thus, even in cases that can be 

classified as some type of allergic asthma, the illness is not medically explained. 

Furthermore, there is no evidence that Mr. Stewart's asthma is attributable to any 

preexisting allergies. It should be noted that if his asthma could be traced to some sort of allergic 

reaction, the question would arise whether his sensitization occurred because of exposure to the 

dust or toxins to which he was indisputedly exposed in Iraq. But there is no medical evidence on 

this subject and the Board made no findings in that regard.

The parties disagree whether the term "medically unexplained" requires VA to identify the 

cause of a specific veteran's illness or may be resolved by general knowledge in the medical 

community about the illness. I fully agree with Judge Pietsch's analysis and conclusion that the 

determination of whether a condition is a MUCMI must be based on an individual veteran's 

circumstances. I emphasize, however, that there is no evidence in this record as to the etiology of 

asthma, either generally or in Mr. Stewart's particular case. 

I would invalidate the Secretary's implementing regulation, 38 C.F.R. § 3.317(a)(2)(ii), as 

inconsistent with the statute and internally inconsistent. Nevertheless, I agree with the majority 

that the Board's October 20, 2015, decision should be set aside and this matter remanded for further 

development to determine whether Mr. Stewart's asthma is a medically unexplained chronic 

multisymptom illness in his particular situation, followed by readjudication.

SCHOELEN, Judge, concurring in part and dissenting in part: I join the Court's decision 

except that I respectfully dissent from that portion of the opinion pertaining to the specific etiology 

of a veteran's disease (Part II.B.). The dispute between the parties is whether the phrase "medically 

unexplained" requires VA to identify the etiology of a veteran's illness or whether VA may rely 

 

62 Id. at 168 (italics in original).

63 See id. for a description of different types of asthma, some of which are not associated with any allergic 

reaction to known substances. 
22

on the general knowledge in the medical community about the illness. The appellant argues that 

VA must identify the etiology of his individual asthma. The Secretary, on the other hand, contends 

that the term "etiology" in § 3.317(a)(2)(ii) refers to the cause of the diagnosed illness generally, 

rather than a specific etiological cause pertaining to an individual veteran. 

The majority concludes that if the etiology of a veteran's specific illness is unknown, the 

illness may be considered a MUCMI, even though the etiology of the disease as it generally affects 

the public is known. The majority reaches this conclusion without pointing to specific language in 

either the statute or its implementing regulation. To the contrary, the statute and regulation 

specifically mention illnesses that are MUCMIs (fibromyalgia, chronic fatigue syndrome, and 

irritable bowel syndrome), as well as specific illnesses (diabetes and multiple sclerosis) that are 

not MUCMIs, without qualifying whether the etiology of a veteran's illness is known. See Tropf 

v. Nicholson, 20 Vet.App. 317, 320 (2006) (stating that the plain meaning of a regulation is 

controlling). Surely, had Congress intended that the defining characteristic of a MUCMI was 

whether the etiology of a veteran's specific illness was understood, it would have clearly stated 

this in the statute. 

Instead of relying on the statutory or regulatory language, the majority relies upon 

Goodman v. Shulkin, 870 F.3d 1383 (Fed. Cir. 2017), to bolster its broad holding. As the majority 

correctly notes, Mr. Goodman was seeking presumptive service connection for rheumatoid arthritis 

(RA) as a MUCMI. In denying Mr. Goodman's claim, the Board relied on a medical opinion that 

concluded that RA was not a MUCMI because the etiology and pathophysiology of that condition 

were partially understood on a general basis in the medical community. This Court affirmed the

Board decision. 

On appeal, Mr. Goodman argued to the Federal Circuit that the Court effectively allowed 

the VA medical expert to establish a general rule that was binding in future claims that RA is not 

a MUCMI. Id. at 1386. Mr. Goodman claimed that the Court's ruling "'expand[ed] the authority of 

the medical expert beyond the facts of an individual case and improperly delegate[ed] authority 

for determining a qualifying disease to an individual physician.'" Id. The Federal Circuit soundly 

rejected this argument and held that § 3.317 did not "prohibit medical professionals from 

professing whether certain medical diseases may constitute a MUCMI" and that such medical 

opinions could be used by VA adjudicators when it made determinations in individual claims that 

came before it. Id. at 1387. Further, the Federal Circuit observed that the Board has "'the authority 
23

to determine on a case-by-case basis whether additional diseases meet the criteria [for a MUCMI] 

in the same manner as they make other determinations necessary in deciding claims.'"64 Id. 

(quoting 75 Fed. Reg. 61,995, 61,995 (October 7, 2010)). Ultimately, the Federal Circuit stated: 

"[W]e hold that VA adjudicators may rely on a medical examiner's evaluation of whether a 

veteran's condition qualifies as a MUCMI," id. and that the Board may consider medical evidence 

along with "other facts of record" to determine whether the "claimant has proven, based on the 

claimant's unique symptoms, the existence of a MUCMI," id. at 1380. 

The majority seizes upon this language to conclude that Goodman endorses the notion that 

VA must pinpoint the etiology of Mr. Stewart's individual asthma. However, Goodman clearly 

does not make this broad pronouncement. Rather, the Federal Circuit held that the medical 

advisor's statement did not violate the requirement that VA adjudications are to be conducted on a 

case-by-case basis. In doing so, the Court affirmed the Board's reliance on a medical opinion that 

was based on the facts of Mr. Goodman's claim, including his individual symptoms, but also 

opined that RA had a partially explained and medically accepted etiology and pathophysiology. 

Thus, if anything, Goodman endorses VA's practice of relying on medical opinions that address 

the etiology of a disease generally, even though the medical opinion does not pinpoint the specific 

etiology of the individual claimant's disease.65

 

64 By using the language "in the same manner as they make other determinations necessary in deciding 

claims," the Federal Circuit recognizes that, as in other service-connection claims, the Board reviews a medical 

examiner's findings along with other relevant evidence to decide whether the evidence before it establishes that the 

claimant has a condition that is related to service. 

65 The only other basis that the majority gives for its broad holding is the fact that the Secretary has 

acknowledged that whether an illness constitutes a MUCMI requires a medical opinion and that treatise evidence is 

not sufficient evidence to support a Board finding that an illness constitutes a MUCMI. However, VA generally does 

not rely on treatise evidence, alone, to decide whether a veteran's disability is related to service. To the contrary, this 

Court has long recognized that treatise evidence may help a veteran establish entitlement to service connection when 

it is accompanied by a medical examiner's opinion relating the particular veteran's illness to service. See Sacks v. West, 

11 Vet.App. 314, 317 (1998) (treatise evidence when combined with an opinion of a medical professional can provide 

important nexus evidence to support a service-connection claim). Moreover, the observation by the majority that a 

medical opinion is needed to identify an illness as a MUCMI does not lend any insight to the question whether a doctor 

must pinpoint the specific etiology of a veteran's illness or rely on the knowledge in the medical community about the 

cause of the diagnosed illness generally.