       NOTE: This disposition is nonprecedential.


  United States Court of Appeals
      for the Federal Circuit
                ______________________

               ZAWADI Z. ALLEN, SR.,
                 Claimant-Appellant

                           v.

     ROBERT A. MCDONALD, SECRETARY OF
            VETERANS AFFAIRS,
               Respondent-Appellee
             ______________________

                      2015-7003
                ______________________

   Appeal from the United States Court of Appeals for
Veterans Claims in No. 13-395, Judge Alan G. Lance Sr.
                ______________________

                Decided: June 20, 2016
                ______________________

   CONRAD R. LEIKAUF, I, Leikauf & Mulcahey Law,
Branchburg, NJ, for claimant-appellant.

    BARBARA E. THOMAS, Commercial Litigation Branch,
Civil Division, United States Department of Justice,
Washington, DC, for respondent-appellee. Also represent-
ed by BENJAMIN C. MIZER, ROBERT E. KIRSCHMAN, JR.,
ALLISON KIDD-MILLER; JONATHAN ELLIOTT TAYLOR, DAVID
J. BARRANS, RACHAEL BRANT, BRIAN D. GRIFFIN, TRACEY
2                                        ALLEN   v. MCDONALD



PARKER WARREN, Office of General Counsel, United
States Department of Veterans Affairs, Washington, DC.
               ______________________

    Before PROST, Chief Judge, TARANTO and CHEN, Circuit
                           Judges.
PROST, Chief Judge.
    Zawadi Z. Allen, Sr. appeals from a final judgment of
the United States Court of Appeals for Veterans Claims
(“Veterans Court”) denying service connection for chronic
sinusitis. We affirm.
                       BACKGROUND
    Mr. Allen served in the United States Army from No-
vember 1989 until November 1993. His service included
active combat in the Persian Gulf War between January
and April 1991. He received the Army Commendation
Medal for “exceptionally meritorious service.”
    While on duty, Mr. Allen was exposed to smoke from
burning oil fields and several nerve agents. In particular,
on March 10, 1991, Mr. Allen’s unit was serving in an
area near Khamisiyah, Iraq, where several rockets were
destroyed. The Department of Defense reported in a July
1997 letter that, when these rockets were destroyed, “the
nerve agents sarin and cyclosarin may have been released
into the air” and “exposure to a very low level of nerve
agents was possible.” Supplemental App. 169.
    Mr. Allen’s October 1989 enlistment exam reported
that he was in “excellent” health and had no history of
sinusitis, allergies, asthma, or respiratory problems. He
was seen several times throughout his service for respira-
tory ailments, but was never diagnosed with sinusitis. In
December 1989, Mr. Allen was treated for a sore throat,
nasal drainage, chest congestion, and a cold. In May
1991, Mr. Allen was examined and reported that he had
sinusitis, eye trouble, chronic or frequent colds, swollen or
ALLEN   v. MCDONALD                                       3



painful joints, and dizziness or fainting spells, but the
examining officer concluded that his sinuses, mouth and
throat, nose, and head were normal. Between March and
July 1992, Mr. Allen was seen several times for chest
pain, coughing, and shortness of breath. Between Sep-
tember 1992 and March 1993, Mr. Allen was treated
several times for severe fatigue, a sore throat, and conges-
tion. Nevertheless, at the end of his service, in October
1993, Mr. Allen stated on a medical form that he was in
“excellent” health. He reported that he suffered from
swollen and painful joints and chronic or frequent colds,
but indicated that he did not have sinusitis.
    Between 1993 and 2005, Mr. Allen was treated spo-
radically for various ailments, including joint pain, ab-
normal sensation in his ear, an upper respiratory
infection, breathlessness, and fatigue. He was never seen
for or diagnosed with sinusitis.
    In May 2005, Mr. Allen filed a claim seeking service-
connected benefits for sinusitis. In July 2005, the U.S.
Department of Veterans Affairs (“VA”) regional office
(“RO”) sent Mr. Allen a letter providing information on
the benefits process and describing additional evidence he
would need to provide to support of his claim. In August
2005, Mr. Allen submitted a letter from his mother, Nettie
Grier, which stated that when Mr. Allen was discharged
he “complained about his sinuses bring congested” and
that he still had certain sinus problems. On September
14, 2005, the RO denied Mr. Allen’s claim on the basis
that there was no record of treatment for sinusitis.
    Mr. Allen filed a Notice of Disagreement on Septem-
ber 28, 2005. On October 18, 2005, Mr. Allen obtained a
private medical examination, which concluded he had
chronic sinusitis. Mr. Allen submitted this report to the
RO. Nevertheless, the RO again denied Mr. Allen’s claim.
    Mr. Allen appealed to the Board of Veterans Appeals
(“Board”) on November 8, 2006. As additional support for
4                                         ALLEN   v. MCDONALD



his claim, Mr. Allen submitted a letter from a pathologist
and family member, Dr. Monnette Baker, stating that she
had reviewed literature relating to Gulf War veterans and
that “it is [her] opinion that the onset of many illnesses,
including chronic sinusitis, may be a consequence of
serving in the Gulf War.” Supplemental App. 125. Mr.
Allen also testified before the Board that his sinus prob-
lems began while he was serving in the Gulf War and he
has continuously had problems since.
    The Board issued a decision on December 14, 2009
finding that Mr. Allen had shown that he had a current
disability of chronic sinusitis and an in-service injury that
he had been exposed to nerve agents, but remanding
because a medical exam was needed to determine if Mr.
Allen’s sinusitis was connected to his in-service injury. A
VA physician conducted an examination on February 17,
2010, but concluded that “[g]iven the silent medical record
during the military and in the 12 years following, I would
be resorting to mere speculation to link [Mr. Allen’s]
current complaints of chronic sinusitis with his military
exposure during service.” Id. at 108. Mr. Allen’s case was
returned to the Board, which remanded again on August
16, 2011, instructing the physician to either provide a
“more definitive comment on the etiology of [Mr. Allen’s]
chronic sinusitis” or specifically explain why it was not
possible to render such an opinion. Id. at 86–89. The VA
physician reviewed literature from the VA’s website and
Mr. Allen’s medical records and concluded that “[b]ased
on the literature and the treatment records, I am still
resorting to speculation to say that his exposure to vari-
ous toxic agents in the Persian Gulf caused [Mr. Allen’s]
chronic sinusitis.” Id. at 80.
     On December 17, 2012, the Board issued a decision
denying Mr. Allen’s claim for service connection for sinus-
itis. It found that, although Mr. Allen had shown that he
had an in-service injury (“environmental exposure”) and a
present disability (sinusitis), he failed to establish a nexus
ALLEN   v. MCDONALD                                        5



between the two, as neither the VA physician nor Dr.
Baker could do more than speculate as to nexus or state
that nexus was “possible.” It also found that Mr. Allen
could not alternatively establish nexus by showing conti-
nuity of symptomatology under 38 C.F.R. § 3.303(b)
because he had not shown that he had sinusitis during
service. It found that both he and his mother were com-
petent to testify as to his symptoms, but this testimony
was not credible because it conflicted with Mr. Allen’s
contemporaneous service records. It also found that the
VA had fulfilled its duty to assist.
    The Veterans Court affirmed. It concluded that the
Board provided an adequate statement of reasons and
bases to support its decision, did not err in finding that
the benefit of the doubt rule was inapplicable, correctly
found that the VA satisfied its duty to assist, and disa-
greed with the remainder of Mr. Allen’s challenges.
    Mr. Allen timely appealed to this court. We have ju-
risdiction under 38 U.S.C. § 7292.
                        DISCUSSION
    Our jurisdiction to review decisions of the Veterans
Court is limited by statute. We may review a Veterans
Court decision with respect to the validity of a decision on
a rule of law or the validity or interpretation of any stat-
ute or regulation that was relied upon by the Veterans
Court in making its decision. 38 U.S.C. § 7292(a). Unless
a constitutional issue is presented, we have no jurisdic-
tion to review questions of fact or the application of a law
or regulation to a particular set of facts. Id. § 7292(d)(2).
                              I
     To establish service connection for a present disabil-
ity, a veteran must show that: (1) he suffers from a pre-
sent disease or disability; (2) there was an in-service
incurrence or aggravation of a disease or injury; and (3)
there is a causal link or nexus between the present disa-
6                                       ALLEN   v. MCDONALD



bility and the disease or injury that was incurred or
aggravated during service (“the Shedden factors”). Shed-
den v. Principi, 381 F.3d 1163, 1167 (Fed. Cir. 2004). The
Board found that Mr. Allen had satisfied the first two
requirements; thus, the issues on appeal focus on whether
there is a nexus between Mr. Allen’s present disability
(sinusitis) and in-service injury (environmental exposure).
     Mr. Allen argues that the Veterans Court and the
Board erred in finding there was no nexus because the
Board failed to liberally construe his “filings” and failed
apply the “benefit of the doubt rule” according to 38
U.S.C. § 5107(b). He also argues that it failed to consider
his combat status in weighing his lay evidence, as re-
quired by 38 U.S.C. § 1154. Had the Board appropriately
followed these principles, Mr. Allen argues, it would have
found that a generous reading of Dr. Baker’s medical
opinion combined with his and his mother’s lay state-
ments established the requisite nexus.
    As an initial matter, to the extent Mr. Allen challeng-
es the Veterans Court’s application of these principles to
the facts of this case, we lack jurisdiction. We do, howev-
er, have jurisdiction to review whether the Veterans
Court applied the wrong law. We address each of Mr.
Allen’s arguments in turn.
    First, Mr. Allen contends that the Veterans Court and
the Board failed to “give a sympathetic reading to the
veteran’s filings by determining all potential claims raised
by the evidence, applying all relevant laws and regula-
tions.” Moody v. Principi, 360 F.3d 1306, 1310 (Fed. Cir.
2004) (internal quotation marks omitted). Mr. Allen is
correct that the VA has a duty to fully and sympathetical-
ly develop a veteran’s claim, id.; however, this does not
negate the fact that, once Mr. Allen’s claim had been
developed, he still bore the burden of proving his claim.
38 U.S.C. § 5107(a) (“a claimant has the responsibility to
present and support a claim for benefits”). Mr. Allen does
ALLEN   v. MCDONALD                                          7



not appear to contend that his claim should have been
developed more broadly; instead, his challenge only
concerns the Board’s evaluation of whether he presented
evidence sufficient to establish nexus. In this context, the
Board applied the correct legal framework by evaluating
whether Mr. Allen, as the claimant, met his burden of
proof.
    Mr. Allen also argues that the Veterans Court and the
Board failed to apply the benefit of the doubt rule. Sec-
tion 5107(b) instructs that “[w]hen there is an approxi-
mate balance of positive and negative evidence regarding
any issue material to the determination of a matter, the
Secretary shall give the benefit of the doubt to the claim-
ant.” 38 U.S.C. § 5107(b). Here, however, the Board did
not find that there was such an “approximate balance.”
To the extent Mr. Allen challenges this finding, it is a
factual determination beyond our review. Given this, we
accept the Board’s finding and conclude, on that basis,
that the Board did not err in declining to apply the benefit
of the doubt rule.
    Next, Mr. Allen argues that that Veterans Court and
the Board erred because they failed to consider his combat
status in assessing his and his mother’s lay statements.
Section 1154(b) provides that, in the case of a combat
veteran, “the Secretary shall accept as sufficient proof . . .
satisfactory lay or other evidence . . . if consistent with the
circumstances, conditions, or hardships of such service.”
38 U.S.C. § 1154(b). However, we held in Davidson v.
Shinseki that § 1154(b) only applies to the second Shed-
den factor: whether there was an in-service injury. 581
F.3d 1313, 1315–16 (Fed. Cir. 2009) (stating that
“§ 1154(b) concerns only whether a disease was incurred
or aggravated in service-not whether the disease was the
principal or a contributory cause of death”). Here, Mr.
Allen only challenges the Board’s assessment of the third
Shedden factor: nexus. Thus, Mr. Allen’s combat status
8                                        ALLEN   v. MCDONALD



has no relevance to the Board’s consideration of his and
his mother’s lay evidence.
    In addition to correctly disregarding § 1154(b), the
Board correctly assessed Mr. Allen’s lay evidence. In
evaluating lay evidence, the Board “cannot determine
that lay evidence lacks credibility merely because it is
unaccompanied by contemporaneous medical evidence.”
Buchanan v. Nicholson, 451 F.3d 1331, 1337 (Fed. Cir.
2006). Instead, “as fact finder, [the Board] is obligated to,
and fully justified in, determining whether lay evidence is
credible in and of itself, i.e., because of possible bias,
conflicting statements, etc.” Id. This is precisely what
the Board did here: it did not dismiss Mr. Allen’s or his
mother’s statements out of hand, but considered them
along with his contemporaneous service records, which
reported that he did not have sinusitis. It then, as it
should have, made credibility determinations about this
lay evidence. We discern no legal error in this process.
    The remainder of Mr. Allen’s arguments on the nexus
issue concern the Board’s conclusion regarding nexus
itself. For example, Mr. Allen’s arguments that the Board
did not adequately credit Dr. Baker’s letter, the testimony
from his mother, or medical records of other respiratory
conditions are merely disagreements with how the Board
weighed the evidence before it. We lack jurisdiction to
review these determinations.
                             II
    If a veteran cannot establish nexus, he may, in some
cases, prove his claim for service connection by showing a
“continuity of symptomology” under 38 C.F.R. § 3.303(b).
However, this alternative route is not available to Mr.
Allen. We held in Walker v. Shinseki that 38 C.F.R.
§ 3.303(b) only applies to chronic conditions listed in 38
C.F.R. § 3.309(a). 708 F.3d 1331, 1335–38 (Fed. Cir.
2013). “Sinusitis” is not one of these conditions. 38
C.F.R. § 3.309(a). Thus, under current law, Mr. Allen
ALLEN   v. MCDONALD                                       9



cannot establish service connection through continuity of
symptomology.
    Mr. Allen nevertheless argues that the Veterans
Court and the Board erred in denying service connection
because his lay evidence established continuity of symp-
tomology. The Board’s decision, which issued prior to our
decision in Walker, considered continuity of symptomology
and found that, because Mr. Allen’s lay evidence contra-
dicted contemporaneous medical records, it was insuffi-
cient to establish continuity of symptomology.          See
Supplemental App. 68–72. Even if we were to evaluate
the Board’s decision on this point, we would discern no
reversible error. As discussed above, the Board applied
correct legal standards in its assessment of Mr. Allen’s lay
evidence and determined that it was not credible. Thus,
even if a continuity of symptomology analysis were not
foreclosed by Walker, Mr. Allen’s arguments on this point
would fail.
                            III
    Mr. Allen’s remaining arguments, including his ar-
gument that the VA did not fulfill its duty to assist under
38 U.S.C. § 5103A(a)(1) and his argument that the Board
did not adequately explain the reasons and bases for its
decision in accordance with 38 U.S.C. § 7104(d)(1), con-
cern application of fact to law. We do not have jurisdic-
tion to review these issues.
    We also disagree that Mr. Allen was denied due pro-
cess. The VA, in adjudicating his claim, afforded him
repeated opportunities to present evidence and to chal-
lenge the VA physician’s opinions. It also notified Mr.
Allen regarding the elements of his claim and the types of
evidence he would need to present to meet his burden of
proof. Whatever due process requires, it requires no more
than this.
10                                       ALLEN   v. MCDONALD



    We have carefully considered the remainder of Mr. Al-
len’s arguments and have determined that they lack
merit. For the foregoing reasons, we affirm the Veterans
Court’s decision and deny Mr. Allen’s request for service
connection for sinusitis.
                       AFFIRMED
                           COSTS
     Each party shall bear their own costs.
