Koehn v. Secretary of Health and Human Services ( 2013 )


Menu:
  •      In the United States Court of Federal Claims
    No. 11-355V
    (Originally Filed: December 3, 2013)
    (Reissued: December 19, 2013)*
    **********************
    C. K., as Mother and Next
    Friend of V. K.,
    Vaccine case; off-table
    claim; Althen; petitioner’s
    Petitioner,
    challenge to the Special
    Master’s decision; HPV
    v.
    vaccine; Gardasil;
    systemic juvenile
    SECRETARY OF HEALTH AND
    idiopathic arthritis
    HUMAN SERVICES,
    Respondent.
    **********************
    OPINION
    Currently before the court is petitioner’s motion for review of the
    Special Master’s ruling of May 30, 2013 denying compensation for an injury
    allegedly caused by a vaccine. The matter is fully briefed, and oral argument
    was held on October 18, 2013. For the reasons explained below, we deny
    petitioner’s motion for review.
    On June 6, 2011, petitioner, C. K., filed a petition for compensation
    under the National Childhood Vaccine Injury Act, 42 U.S.C. §§ 300aa-1 to-34
    (2006) (“Vaccine Act”), on behalf of her minor daughter, V. K. (“V”). The
    petition alleges that V developed systemic juvenile idiopathic arthritis
    (“SJIA”) because she received two doses of the human papillomavirus
    *
    This opinion was initially withheld from publication to provide the
    parties with a period of time to propose redactions. The court adopted the
    parties’ proposed redactions, which were made to protect petitioner’s identity.
    The opinion is now prepared for release.
    (“HPV”) vaccine. Specifically, petitioner’s theory of the case was that the
    HPV vaccine causes an increase in particular cytokines, the same cytokines are
    implicated in SJIA, and therefore the HPV vaccine can be a significant factor
    in causing SJIA. After conducting a hearing, reviewing epidemiological
    studies, and weighing the evidence provided by the experts, the Special Master
    concluded that petitioner had failed to establish a persuasive theory of
    causation and denied petitioner’s request for compensation. See Koehn v.
    Sec’y of Health & Human Servs., No. 11-355V, 
    2013 WL 3214877
     (Fed. Cl.
    Spec. Mstr. May 30, 2013) (hereinafter “Decision”).
    BACKGROUND1
    I.       Facts
    V was born in 1995. She was generally healthy throughout childhood.
    She had no remarkable medical events for the first twelve years of her life
    other than asthma. Dr. Elena R. Regala, V’s routine physician, administered
    the first dose of the HPV2 vaccine in February of 2008 during a regular check-
    up. The brand of HPV vaccine given to V was Gardasil, which is
    manufactured by Merck.3 Gardasil provides immunization against four strands
    of virus: HPV-6, HPV-11, HPV-16, and HPV-18, and is therefore referred to
    as a quadrivalent HPV vaccine.
    The HPV vaccine contains virus-like particles (“VLP”) that were
    created from the L1 protein of the human papillomavirus. In order to generate
    a robust immune response sufficient to generate long term immunity, the
    1
    The facts are derived from the Special Master’s decision.
    2
    There are over 130 strands of HPV. Some of these strands cause
    warts. Two strains of the virus, HPV 16 and HPV 18, are known to cause
    cancer. For a more thorough description of symptoms caused by an HPV
    infection, see Decision at *2.
    3
    The other brand of HPV vaccine discussed in some of the studies
    considered by the Special Master is Cervarix, which provides immunity against
    HPV strands 16 and 18. Cervarix differs from Gardasil in that it provides
    immunity against only two strains of HPV and contains a lipid and aluminum
    salt adjuvant known as AS04.
    2
    vaccine contains an adjuvant4 and is delivered intramusculary. This vaccine
    can cause the host to produce more antibodies than he or she would have
    produced in response to a natural infection.
    The second dose of Gardasil was given to V on April 18, 2008. On or
    around June 21, 2008, V experienced a rash all over her body. This caused her
    on June 24, 2008 to visit Dr. Regala, who prescribed Benadryl and prednisone
    for what Dr. Regala believed to be an allergic reaction. Within three days, V’s
    rash had disappeared. After V stopped taking the prednisone, she developed
    pain in multiple places including her knees, thighs, and calves. V was admitted
    to Marian Medical Center on June 28, 2008, for severe joint pain and high
    fever. While at the hospital, V received medical tests, saw a Rheumatologist,
    and was prescribed prednisone. On July 2, 2008, she was discharged from the
    hospital with a presumptive discharge diagnosis of juvenile idiopathic arthritis.
    At the time she was discharged, V no longer had a fever or joint pain but still
    had a rash.
    The cause of SJIA is unknown. The annual incidence rate of this
    disease in children less than 16 years of age is between 0.3 and 0.8 out of every
    100,000. Children with SJIA exhibit symptoms of arthritis and a recurring
    fever for at least two weeks as well as a rash, enlargement of the liver or
    spleen, lymphadenopathy, or serositis. When a child with SJIA has active
    inflamation, commonly referred to as a flare, he or she may experience muscle
    pain, pain in more than one joint, a fever, and a rash. SJIA may also cause
    problems with the heart, liver, or in rare cases, the central nervous system.
    Many of the symptoms described above are associated with a
    dysfunction of the innate immune response and a corresponding increase in the
    production of pro-inflammatory cytokines. A cytokine is a protein which is
    released almost immediately by certain cells when they come into contact with
    a specific antigen. When the cytokine is released it signals other cells to
    generate an immune response. In short, cytokines are like smoke signals
    which cells send out to indicate the presence of an invasion and to elicit a
    defensive response. Respondent’s expert testified that the cytokine response
    4
    The particular adjuvant contained in Gardasil is amorphous aluminum
    hydroxyphosphate sulfate, which stimulates antibody production.
    3
    is almost universal.5 There are, however, specific cytokines which are
    recognized as being either anti-inflammatory or pro-inflammatory. Pro-
    inflammatory cytokines can lead to fever, increased vascular permeability, and
    increased synovial inflammation. “The specific pro-inflammatory cytokines
    that have been implicated in the development of SJIA include interleukin
    (“IL”) 1, IL-6, IL-7, IL-8, IL-18, macrophage inhibitory factor, and tumor
    necrosis factor [(“TNF”)].” Decision at *8. Because of the involvement of
    these cytokines, which are part of the innate immune system, SJIA is classified
    as an autoinflammatory disease as opposed to an autoimmune disease.6
    SJIA is treated by medications which minimize inflamation, including
    some combination of the following: any nonsteroidal anti-inflammatory
    pharmaceutical such as ibuprofen or naproxen; intravenous immunoglobulin;
    cyclosporine-A; thalidomide; prednisone, which reduces inflamation and
    generally suppresses the immune system; etanercept, which targets and inhibits
    TNF; methotrexate, which is a folic acid inhibitor; tocilizumab, which inhibits
    IL-6 production; and anakinra, which is a IL-1 inhibitor.
    5
    Scientists have identified approximately 40 specific cytokines thus far.
    6
    The distinction between an autoimmune and an autoinflammatory
    disease is made based on the part of the immune system that is dysregulated
    or out of balance. The immune system is comprised of two systems: the
    adaptive and innate. These two systems interact continuously to maintain
    balance. Hr’g Tr. 67-70, June 21, 2012. When the adaptive immune system
    is dysregulated, the autoantibodies and autoreactive T cells do not function as
    they would in a healthy individual and the resultant state is called an
    autoimmune disease. Rheumatoid arthritis is typically understood to be an
    autoimmune disease. When the innate immune system, which involves
    cytokine production by monocytes and neutrophils, functions abnormally, then
    the resulting state is known as an autoinflammatory disease. See Elizabeth D.
    Mellins et al., Pathogenesis of systemic juvenile idiopathic arthritis: some
    answers, more questions, 7 Nature Revs. Rheumatology 416 (2011)
    (hereinafter “Mellins”). Before this distinction was made between
    autoimmune and autoinflammatory diseases, most forms of arthritis were
    generally referred to as autoimmune disorders. SJIA was only recently
    classified as an autoimmune disease. Some scholars continue to broadly
    characterize arthritis as an autoimmune disease and include SJIA in this
    characterization.
    4
    After being discharged from the hospital, V saw a pediatric
    rheumatologist, Dr. Deborah McCurdy, on July 8, 2008, who noted that V’s
    family history included juvenile idiopathic arthritis and concluded that SJIA
    was a likely diagnosis in this case. Dr. McCurdy recorded that V’s
    vaccinations were up to date and that V had received two of three courses of
    the HPV vaccine. Dr. McCurdy communicated these findings to Dr. Regala.
    When Dr. Regala saw V again on August 19, 2008, she administered the third
    dose of HPV vaccine. At the time that V received the third course of Gardasil,
    she was no longer taking prednisone but had started etanercept. A physical
    therapist recorded that on August 25, 2008, V experienced a flare with
    symptoms of fever, rash, and increased joint pain. Dr. McCurdy saw V again
    on September 3, 2008. Dr. McCurdy noted that V complained of having some
    symptoms after stopping prednisone and that V had swollen ankles and knees.
    Dr. McCurdy concluded that V had improved but still showed signs of active
    disease while being treated with methotrexate and etanercept.
    Dr. McCurdy continued to care for V through 2010. On January 12,
    2011, V visited another pediatric rheumatologist, Dr. Alice Hoftman. During
    this visit, Dr. Hoftman recommended that V receive the influenza vaccine.
    Although V had received the influenza vaccine during the previous three years,
    C. K. refused this treatment for her daughter. Dr. Hoftman recorded that C. K.
    was hesitant about giving V the vaccine because of Gardasil. Dr. Hoftman
    explained that there was “‘no data but all vaccines and infections can trigger
    autoimmune response.’” Decision at *10 (quoting Ex. 5 at 28).
    II.    Expert Opinions
    A.     Petitioner’s Expert
    Petitioner offered the testimony of Dr. Michael J. McCabe, Jr., an
    expert in the field of immunology. Dr. McCabe is not a medical doctor and
    does not treat patients. In his report, Dr. McCabe wrote that the cause of
    arthritis is multi-factorial. Genetic susceptibility and environmental triggers
    such as infections and vaccinations are possible causative factors. Dr.
    McCabe’s theory is essentially that the HPV vaccine, which Dr. McCabe
    characterized as a potent immunogen, was the environmental trigger that
    caused V’s immune system to fall out balance resulting in her SJIA. The
    evidence of this is that the vaccine elicited a strong cytokine response which
    involved the same cytokines that are associated with SJIA.
    5
    In support of his theory, Dr. McCabe provided “‘scientific and medical
    literature that implicates pro[-]inflammatory cytokines and inflammatory
    responses and innate immunity in the pathogenesis of systemic juvenile
    arthritis.’” Decision at *12 (quoting Hr’g Tr. 123). One such article was Ligia
    A. Pinto et al., HPV-16 L1 VLP vaccine elicits a broad-spectrum of cytokine
    responses in whole blood, 23 Vaccine 3555 (2005) (hereinafter “Pinto”),
    which Dr. McCabe interpreted as showing an increase in the production of
    particular cytokines in response to the HPV vaccine.7 The Special Master
    summarized the Pinto study as follows:
    Twenty-four women participated in the study. Blood
    specimens were collected before the initial injection, known as
    month zero. Twenty women, then, received a 50 µg dose of
    vaccination without adjuvant and four women received a
    placebo of sterile saline solution. One month later, all women
    were given a second injection of the same substance (either the
    vaccination or a placebo). At month two, more blood was
    drawn. At six months, the women received a third injection. At
    seven months, more blood was drawn.
    The researchers determined the level of cytokines for
    each of the three blood samples after different types of
    stimulation. This process was done “in vitro,” meaning in glass,
    like a test tube. The blood from women who received the
    vaccine and women who received the placebo was evaluated in
    the context of four substances. In the first, the blood was not
    stimulated at all. The researchers refer to this as the “media.”
    In the second, the blood was stimulated with 10 µg of the virus-
    like particle present in the vaccine. In the third, the blood was
    stimulated with 1.0 µg of the virus-like particle. In the fourth,
    the blood was stimulated with a control known as PHA. The
    stimulation was for 24 hours in the absence or presence of L1
    VLP or PHA.
    7
    The HPV vaccine used in the Pinto study provides immunity against
    just one strand of HPV, HPV-16, and did not contain an adjuvant. By contrast,
    the vaccine that V received, Gardasil, provided immunity against four strands
    of HPV, including HPV-16, and contained an adjuvant.
    6
    . . . . [T]he researchers obtained different results
    depending upon whether there was any stimulation. For cells in
    the media–meaning no stimulation–the cytokine levels stayed
    relatively similar from month zero to month two to month seven.
    . . . [S]pontaneous secretion of cytokines in the absence of any
    stimuli (media control) did not show any significant increases
    following vaccination. For blood that was stimulated either with
    10 µg or 1.0 µg of the virus-like particle, cytokines increased.
    Stimulation of cells from vaccine recipients with L1 VLP (10
    µg/ml) induced significant increases in the median levels of
    inflammatory [] cytokines. Similar patterns of cytokine
    production to the ones seen in response to L1 VLP at 10 µg/ml
    were observed when L1 VLP was tested at 1.0 µg/ml.
    Decision at *4 (citations and quotations omitted). The Pinto study included a
    graph that Dr. McCabe used to show how levels of pro-inflammatory cytokines
    like IL-1 beta, IL-6, and TNF alpha increased in response to direct stimulation
    with the L1 VLP.8 Pinto at 3558; see Hr’g Tr. 104. According to Dr.
    McCabe, the particular cytokines that increased in response to the HPV L1
    VLP are the same cytokines, IL-1, IL-6, and TNF, that are dysregulated in
    SJIA. This commonality of cytokines present in response to the HPA vaccine
    and involved in SJIA is the foundation and mechanistic support for Dr.
    McCabe’s theory of causation.
    Dr. McCabe also presented the Special Master with an epidemiological
    study, which evaluated a database of the medical history of approximately
    189,000 women to determine whether these women developed autoimmune
    conditions within 180 days of receiving the quadrivalent HPV vaccine. Chun
    Chao et al., Surveillance of autoimmune conditions following routine use of
    quadrivalent human papillomavirus vaccine, 271 J. Intern. Med. 193 (2012)
    8
    This was not the only study Dr. McCabe relied on to show an increase
    in pro-inflammatory cytokines in response to stimulation with the HPV
    vaccine. Dr. Pinto participated in a more recent study which also showed “that
    various cytokines increased after the administration of a vaccine against
    human papillomavirus.” Decision at *12; see Alfonso García-Piñeres et al.,
    Cytokine and Chemokine Profiles following Vaccination with Human
    Papillomavirus Type 16 L1 Virus-Like Particles, 14 Clinical & Vaccine
    Immunology 984 (2007) (hereinafter “García-Piñeres”).
    7
    (hereinafter “Chao”). One of the diseases that the researchers targeted was
    juvenile rheumatoid arthritis9 (“JRA”). In order to identify JRA within the
    population, the researchers looked for a diagnostic code which included JRA
    and searched for medications commonly prescribed to treat JRA. While the
    researchers did not reach any statistically relevant findings regarding JRA, they
    concluded, “no safety signal for autoimmune conditions was found following
    HPV4 vaccination in routine clinical use.” Id. at 202. Dr. McCabe used this
    study to show that, despite the large population involved in this study, it was
    not large enough to detect any increase in the rate of SJIA following HPV
    vaccination because SJIA is such a rare disease. During the hearing, Dr.
    McCabe explained that there is an absence of epidemiological studies in
    support of his theory because the disease is too rare for scientists to be able to
    generate statistically relevant data. Hr’g Tr. 134-35. Dr. McCabe testified that
    “there is ‘no epidemiology that’s meaningful enough to inform us’ as to
    whether the HPV vaccine causes sJIA.” Decision at *13 (quoting Hr’g Tr.
    141-42).
    The additional literature which Dr. McCabe relied on in his report to
    support the connection between vaccines and SJIA was summarized by the
    Special Master in the following manner:
    Dr. McCabe identified three articles in which the authors stated
    that infections or vaccinations could be the initial cause for
    sJIA. Tr. 136, 142-43, 145-46. One article stated, “in juvenile
    idiopathic arthritis (JIA) a temporal relationship between disease
    onset, childhood vaccination, remissions and flares hint[s] at a
    possible relation of JIA disease activity and vaccinations or
    infections.” Exhibit 15 (Arash Ronaghy et al., Vaccination
    leads to an aberrant FOXP3 T-cell response in non-remitting
    juvenile idiopathic arthritis, 70 Ann. Rheum. Dis. 2037 (2011))
    at 1 [(hereinafter “Roghany”)] . . . . Another article asserted that
    “[o]ne scenario is that infectious agents that are typically
    encountered in childhood initiate sJIA; no single environmental
    trigger has been identified, although this lack of an obvious
    9
    The researchers did not search for SJIA in particular. However, Dr.
    Rose believed that “almost certainly all cases of JRA within the study
    population would have been detected with the methodology utilized by the
    investigators.” Decision at *5 (citations and quotations omitted).
    8
    candidate could point to multiple common agents being capable
    of initiating sJIA.” [Mellins at 417] A third article stated “[i]n
    juvenile idiopathic arthritis, infections and vaccinations have
    been suggested as two candidate triggers.” Exhibit 12 (Berent
    Prakken et al., Juvenile idiopathic arthritis, 377 Lancet 2138
    (2011)) at 2141 [(hereinafter “Prakken”)]. This article
    continued, “but neither has been confirmed as a trigger because
    of a scarcity of proper controlled, prospective studies.” Id.
    Decision at *8 (underlining in original). These articles speculate that there
    might be a link between vaccination in general and the development of SJIA,
    but Dr. McCabe suggested that V was most likely predisposed to develop SJIA
    and that V’s environmental trigger, which substantially caused her to develop
    the disease, was Gardasil. Hr’g Tr. 162, 197.
    Dr. McCabe applied the Bradford-Hill criteria for causation to lend
    credence to his theory. See Sir Austin Bradford Hill, The Environment and
    Disease: Association or Causation?, 7 Proc. of the Royal Society of Medicine
    295 (1965) (hereinafter “Bradford-Hill”). Dr. McCabe believes that the
    temporal sequence, the dose-response relationship, biological plausibility, and
    experimental evidence, all of which are indicative of causation under the
    Bradford-Hill assessment, showed that Gardasil could cause SJIA. Dr.
    McCabe acknowledged that some of the Bradford-Hill criteria, such as
    strength of association and analogy, were not necessarily supportive of his
    theory of causation.
    Regarding the dose-response correlation, Dr. McCabe pointed to
    evidence that V experienced a flare after receiving the third dose of HPV
    vaccine. While acknowledging that V was receiving anti-inflammatory
    treatments when she received the third dose, which made the causation of this
    flare less than clear, Dr. McCabe suggested that the worsening of symptoms
    such as fever, rash, and joint pain during this flare showed that V was
    generating pro-inflammatory cytokines in response to the third dose of
    vaccination.
    Dr. McCabe also noted that studies showed that almost all of the
    patients who received the HPV vaccine seroconverted, or developed sufficient
    antibodies for immunity, within seven months. Based on that data, Dr.
    McCabe concluded that development of disease within seven months after
    receiving an HPV vaccine was evidence of a proximate temporal relationship.
    9
    B.      Respondent’s Expert
    Dr. Carlos Rose, an expert in the field of pediatric rheumatology,
    testified on behalf of the Secretary of Health and Human Services. As a
    pediatric rheumatologist, Dr. Rose routinely treats children with SJI–Dr. Rose,
    however, is not an immunologist, he has not done any research on the HPV
    vaccine, and he has not researched the role of pro-inflammatory cytokines in
    SJIA. After reviewing the literature and Dr. McCabe’s report, Dr. Rose
    concluded that it was mere coincidence that V developed SJIA shortly
    following her second dose of HPV vaccine. Although Dr. Rose acknowledged
    that there is some overlap in the cytokines, particularly IL-1 and IL-6,10 present
    in those recently vaccinated against HPV and those who have SJIA, Dr. Rose
    concluded that this overlap was more likely due to the limited number of
    cytokines that are involved in the stereotypical inflammatory response rather
    than due to a causal relationship with the vaccine.
    In response to the research cited by Dr. McCabe regarding the
    connection between the HPV vaccine and SJIA, Dr. Rose opined that these
    articles were simply hypothesis-generating and did not represent a scientific
    consensus based on evidence and testing. Instead, Dr. Rose explained that, in
    his experience, pediatric rheumatologists generally discuss the safety of HPV
    vaccine for their patients and are not asserting links between SJIA and
    vaccines.
    Dr. Rose also provided his interpretation of the relevance of the Pinto
    study. The media group, i.e. the group not stimulated in vitro, was the most
    relevant to Dr. Rose because it showed a lack of sustained cytokine response
    one month after each dose of vaccination. Dr. Rose observed that the cytokine
    response in this media group remained relatively consistent at months zero,
    two, and seven. This, according to Dr. Rose, is “‘very suggestive that the
    response that this vaccine elicited in these normal people has not been
    sustained.’” Decision at *17 (quoting Hr’g Tr. 225). By contrast, patients with
    SJIA experience a pattern of up-regulated cytokines, which is why they are
    treated with medications that inhibit these specific cytokines. Dr. Rose
    10
    “Dr. Rose stated that his experience as a clinician who has seen some
    (but not all) patients with sJIA improve after taking drugs that control
    interleukin 1 and interleukin 6 informs his belief that these cytokines play a
    role in the disease.” Decision at *16.
    10
    disagreed that the Pinto or García-Piñeres studies showed how a vaccine,
    which may trigger a temporary cytokine response, can cause permanent
    cytokine dysregulation resulting in disease.
    In support of his assertion that SJIA is not caused by the HPV vaccine,
    Dr. Rose cited an epidemiological study of roughly 60,000 individuals that
    found no “evidence of an overall increase in relative risks for autoimmune
    disorders in participants receiving vaccines containing AS04.” Thomas
    Verstraeten et al., Analysis of adverse events of potential autoimmune
    aetiology in a large integrated safety database of AS04 adjuvant vaccines, 26
    Vaccine 6630, 6633 (2008) (hereinafter “Verstraeten”) (comparing the
    development of autoimmune diseases in recipients of three different vaccines,
    only one of which was an HPV vaccine known as Cevarix, containing the
    adjuvant AS04 against a control group of recipients of vaccines that did not
    contain AS04 and finding that there was no greater risk of autoimmune disease
    in the population exposed to AS04).11 Dr. Rose believed that this study would
    have shown a connection between SJIA and the HPV vaccine if one existed.
    C.     Additional Studies the Special Master Considered
    Part of the Bradford-Hill criteria referenced by Dr. McCabe is causation
    judged by analogy, i.e. whether similar vaccines cause results that are similar
    to those alleged by petitioner. Bradford-Hill at 299. To explore this criteria
    of causation, the Special Master looked at analogous studies which evaluated
    whether there was a connection between SJIA and the meningococcal C
    vaccine or the measles, mumps, and rubella (“MMR”) vaccine. Decision at
    *22; see Marloes W. Heijstek et al., Safety of measles, mumps, and rubella
    vaccination in juvenile idiopathic arthritis, 66 Ann. Rheum. Dis. 1384 (2007)
    (hereinafter “Heijstek”); Evelien Zonneveld-Huijssoon et al., Safety and
    Efficacy of Meningococcal C Vaccination in Juvenile Idiopathic Arthritis, 56
    Arthritis & Rheumatism 639 (2007) (hereinafter “Zonneveld-Huijssoon”). The
    subjects of these studies already had juvenile idiopathic arthritis or SJIA and
    11
    At the hearing, the weaknesses of this study were discussed, including
    the fact that the study did not involve Gardasil or the adjuvant contained in
    Gardasil and that the researchers looked for JRA rather than SJIA. Hr’g Tr.
    240-44. Dr. Rose also conceded that a proper epidemiological study of SJIA
    would have to test at least 100,000 individuals because of the rarity of the
    disease. Hr’g Tr. 245-46.
    11
    the researchers sought to determine whether the subjects’ disease symptoms
    worsened after receiving either the meningococcal C or the MMR vaccine.
    The conclusion was the same in each study: the researchers did not observe
    any flares or worsening of disease activity in the subjects with SJIA or juvenile
    idiopathic arthritis following vaccination.
    According to Dr. Rose, these studies show that the meningococcal
    vaccine and the MMR vaccine are safe for use in patients with SJIA. Because
    of this record of safety, Dr. Rose added that Pediatric Rheumatologists
    recommend that their patients receive all vaccines, except those containing live
    viruses. Hr’g Tr. 222.
    III.     The Special Master’s Analysis
    In order to receive compensation for an injury caused by a vaccine
    other than those injuries listed on the Vaccine Injury Table,12 a petitioner must,
    show by preponderant evidence that the vaccination brought
    about her injury by providing: “(1) a medical theory causally
    connecting the vaccination and the injury; (2) a logical sequence
    of cause and effect showing that the vaccination was the reason
    for the injury; and (3) a showing of a proximate temporal
    relationship between vaccination and injury.
    Althen v. Sec’y of Health & Human Servs., 
    418 F.3d 1274
    , 1278 (Fed. Cir.
    2005); see 42 U.S.C. § 300aa-13(a)(1)(A). Petitioner “must provide a
    reputable medical or scientific explanation that pertains specifically to the
    petitioner’s case, although the explanation need only be ‘legally probable, not
    medically or scientifically certain.’”13 Moberly v. Sec’y of Health & Human
    12
    See 42 U.S.C. § 300aa-14(a) (injury table); W.C. v. Sec’y of Health
    & Human Servs., 
    704 F.3d 1352
    , 1356 (Fed. Cir. 2013) (explaining that “[i]n
    a table claim, the petitioner benefits from a statutory presumption of causation
    upon showing that the injury is listed in the Vaccine Injury Table for the
    vaccine received and occurred within the time period in the table” but that “[i]f
    the injury is not listed in the table, the petitioner must prove actual causation
    by a preponderance of the evidence”).
    13
    “[A] finding of causation in the medical community may require a
    (continued...)
    12
    Servs., 
    592 F.3d 1315
    , 1322 (Fed. Cir. 2010) (quoting Knudsen v. Sec’y of
    Health & Human Servs., 
    35 F.3d 543
    , 548-49 (Fed. Cir. 1994)). The theory
    presented by petitioner need only be more likely than not and “close calls
    regarding causation are resolved in favor of injured claimants.” Althen, 
    418 F.3d at 1280
    . “Nonetheless, the petitioner must do more than demonstrate a
    ‘plausible’ or ‘possible’ causal link between the vaccination and the injury; he
    must prove his case by a preponderance of the evidence.” W.C., 704 F.3d at
    1356.
    If petitioner establishes a prima facie case under the Althen elements,
    then the burden shifts to the government to show “‘also by a preponderance of
    evidence, that the injury was in fact caused by factors unrelated to the
    vaccine.’” Id. (quoting Knudsen v. Sec’y of Health & Human Servs., 
    35 F.3d 543
    , 547 (Fed. Cir. 1994)).
    The Special Master analyzed each prong of Althen in turn. Pursuant to
    prong one of Althen, the Special Master considered whether petitioner
    presented a reliable scientific theory under the framework of Daubert v.
    Merrell Dow Pharmaceutical, Inc., 
    509 U.S. 579
    , 592-95 (1993), whether
    petitioner’s theory originated within the scientific community or arose for the
    purposes of litigation, and whether the epidemiological evidence supported
    petitioner’s theory.
    First, the Special Master assessed the reliability of Dr. McCabe’s theory
    by applying three14 of the following Daubert factors:
    (1) whether a theory or technique can be (and has been) tested;
    (2) whether the theory or technique has been subjected to peer
    review and publication; (3) whether there is a known or
    potential rate of error and whether there are standards for
    controlling the error; and, (4) whether the theory or technique
    enjoys general acceptance within a relevant scientific
    13
    (...continued)
    much higher level of certainty than that required by the Vaccine Act to
    establish a prima facie case.” Broekelschen v. Sec’y of Health & Human
    Servs., 
    89 Fed. Cl. 336
    , 343 (2009), aff’d 
    618 F.3d 1339
     (Fed. Cir. 2010).
    14
    The third Daubert factor was not considered by the Special Master
    because neither party introduced evidence regarding the potential rate of error.
    13
    community.
    Terran v. Sec’y of Health & Human Servs., 
    195 F.3d 1302
    , 1316 (Fed. Cir.
    1999) (citing Daubert, 
    509 U.S. at 592-95
    ).
    In the absence of studies that directly tested petitioner’s theory, the
    Special Master explored the Bradford-Hill causation criteria of analogy. The
    Special Master considered two types of analogous studies: those that were
    conducted on animals and those that involved other vaccines. As for the first
    type, neither party identified a study conducted with animals even though an
    animal model for macrophage activation syndrome exists, which is similar to
    SJIA. Dr. Rose explained that the lack of animal studies on this issue was
    likely attributable to the fact that researchers were pursuing more productive
    theories. Then the Special Master considered the Heijstek and Zonneveld-
    Huijssoon studies, which belonged to the second type. These studies showed
    no disease aggravation when the test subjects who had JIA or SJIA were
    vaccinated with the meningococcal C or the MMR vaccination. The Special
    Master wrote that these “studies suggest that when researchers have explored
    whether vaccinations affect juvenile idiopathic arthritis, they have not found
    that the vaccine worsens the disease.” Decision at *22. The Special Master
    acknowledged that these studies contained some factual differences from the
    present case, but concluded that “[b]ecause they are studies, the Heijstek and
    Zonneveld-Huijssoon findings are entitled to more weight than speculative
    passages in other articles.” 
    Id.
     The Special Master concluded that the
    analogous evidence weighed against petitioner’s case, or was, at best, neutral.
    Next, the Special Master observed that Dr. McCabe’s theory was
    unprecedented and had not been published or peer reviewed, although the
    Special Master noted that Dr. McCabe relied on peer reviewed and published
    articles in support of his theory. Specifically, the Special Master discussed Dr.
    McCabe’s reliance on the Pinto experiment to show an increase in cytokines
    seven months after vaccination. Dr. McCabe had drawn that result from the
    part of the experiment in which researchers had stimulated blood samples from
    vaccinated individuals with VLP. Dr. Rose agreed with Dr. McCabe that an
    increase in the cytokine response would follow from direct stimulation with
    the VLP. However, Dr. Rose opined that the most relevant part of the Pinto
    study to the present case was the “media” column, which showed that the level
    of cytokines present in the blood is relatively stable when it is left alone
    following vaccination. The Special Master found Dr. Rose’s interpretation of
    the Pinto experiment more persuasive. According to the Special Master, this
    14
    evidence did not weigh in favor of finding that petitioner’s theory is more
    likely than not.
    While the Special Master acknowledged that petitioner had provided the
    Prakken article, which shows that some scientists may be hypothesizing about
    a possible link between vaccination and SJIA, the Special Master noted that
    one equivocal article did not constitute “evidence that the relevant scientific
    community generally accepts the theory that Gardasil can cause sJIA.”
    Decision at *24. Given that Dr. Rose is the head of pediatric rheumatology at
    the Alfred I. DuPont Hospital for Children, the Special Master believed that
    Dr. Rose would know if pediatric rheumatologists were discussing a possible
    link between Gardasil and SJIA. However, Dr. Rose testified that pediatric
    rheumatologists were not discussing whether Gardasil caused SJIA. Rather,
    pediatric rheumatologists, including Dr. Rose, generally recommend that their
    patients receive all vaccines except those that contain a live virus. The Special
    Master found that the relevant scientific community, at this time, does not
    accept the theory that Gardasil can cause SJIA.
    Next, the Special Master analyzed the epidemiological studies provided
    by respondent. One of these articles, authored by Chao, studied the effects of
    Gardasil in upwards of 189,000 young women. The Special Master noted that
    the researchers in this study did not find a cluster of autoimmune disease onset
    in relation the vaccine. The Special Master then turned to the Verstraeten
    article, which, although he found to be somewhat weak because of the small
    sample size and because the researchers tested Cervarix instead of Gardasil,
    “[t]aken together, the Verstraeten and the Chao articles are an additional (but
    not decisive) reason for finding that Dr. McCabe’s theory that a vaccine
    against human papillomavirus can cause sJIA to be unlikely.” Decision at *26.
    Lastly, the Special Master noted that Dr. McCabe developed his theory
    of causation for the purpose of litigation. The Special Master weighed this
    fact against petitioner’s theory under the Althen prong-one analysis, which
    considers whether petitioner has put forth a medical theory causally connecting
    the vaccination and the injury. After reviewing the totality of petitioner’s
    theory, the Special Master found it problematic that, even if he accepted “the
    proposition that pro-inflammatory cytokines contribute to the course of sJIA,
    this observation does not identify the causes of the disease because something
    must initiate the increase in cytokines.” Decision at *8. Ultimately, the
    Special Master found that Dr. McCabe’s theory of causation contained
    sufficient gaps to make it unpersuasive and petitioner therefore failed to prove
    15
    a medical theory that more likely than not the vaccination was causally
    connected to the injury.
    Although the Special Master was not required to reach conclusions
    about the remaining Althen prongs after holding that petitioner had failed to
    prove prong one, he noted that the record did not support a finding that
    development of SJIA within a seven-month interval was sufficient to establish
    a proximate temporal relationship. Specifically, the Special Master found that
    the Pinto experiment undermined Dr. McCabe’s proposed seven-month
    interval for the onset of SJIA symptoms because the cytokine response to
    stimulation with VLP was immediate in the Pinto experiment. While Dr.
    McCabe attempted to explain the delay between vaccination and symptom
    onset with a theory of amplification, the Special Master saw the media portion
    of the Pinto study as contradictory because cytokines in this group remained
    relatively constant over time. Additionally, the Special Master deduced that
    the evidence provided about V did not persuasively show that she developed
    SJIA because of the HPV vaccine. After reviewing Dr. McCabe’s theory, Dr.
    Rose’s contradictory opinion, and the evidence presented by each expert, the
    Special Master concluded that petitioner’s theory “contain[ed] sufficient gaps
    to make it unpersuasive.” Decision at *26.
    DISCUSSION
    This court has jurisdiction to review decisions of the special masters in
    accordance with 42 U.S.C. § 300aa-12. We review the special master’s
    decision under the standard articulated in 42 U.S.C. § 300aa-12(e) and can
    only set aside “findings of fact or conclusion of law” that were “arbitrary,
    capricious, an abuse of discretion, or otherwise not in accordance with law.”
    42 U.S.C. § 300aa-12(e)(2); see Carson v. Sec’y of Health & Human Servs.,
    
    727 F.3d 1365
    , 1368 (Fed. Cir. 2013) (describing how the reviewing court
    should “give no deference to the . . . Special Master’s determinations of law,
    but uphold the Special Master’s findings of fact unless they are arbitrary or
    capricious”). “The arbitrary and capricious standard of review is difficult for
    [a petitioner] to satisfy with respect to any issue, but particularly with respect
    to an issue that turns on the weighing of evidence by the trier of fact.” Lampe
    v. Sec’y of Health & Human Servs., 
    219 F.3d 1357
    , 1360 (Fed. Cir. 2000).
    “Weighing the persuasiveness of particular evidence often requires a finder of
    fact to assess the reliability of testimony, including expert testimony, and we
    have made clear that the special masters have that responsibility in Vaccine
    Act cases.” Moberly v. Sec’y of Health & Human Servs., 
    592 F.3d 1315
    , 1325
    16
    (Fed. Cir. 2010). Special masters have discretion to weigh the evidence and
    “reversible error is ‘extremely difficult to demonstrate’” unless the special
    master has failed to consider the relevant evidence of record, drawn
    implausible inferences or failed to articulate a rational basis for the decision.
    Lampe 
    219 F.3d at 1360
     (quoting Hines v. Sec’y Health & Human Servs., 
    940 F.2d 1518
    , 1528 (Fed. Cir. 1999)). The reviewing court does “not reweigh the
    factual evidence, assess whether the special master correctly evaluated the
    evidence, or examine the probative value of the evidence or the credibility of
    the witnesses–these are all matters within the purview of the fact finder.”
    Porter v. Sec’y of Health & Human Servs., 
    663 F.3d 1242
    , 1249 (Fed. Cir.
    2011).
    Petitioner makes four challenges to the Special Master’s decision. We
    address each allegation in turn.
    I.     Whether the Special Master failed to consider the record as a
    whole
    Petitioner claims that the Special Master failed to consider the whole
    record in his decision. See Dickerson v. Sec’y of Health & Human Servs., 
    35 Fed. Cl. 593
    , 601 (1996) (“[F]ailure to examine the full record and provide
    sufficient findings constitutes error.”). Petitioner believes that, if the Special
    Master had considered the entire record, he would have seen that petitioner
    presented a plausible theory supported by the scientific evidence and research.
    Respondent replies that the Special Master did not exclude any
    evidence and that he considered “all ‘relevant and reliable evidence governed
    by principles of fundamental fairness to both parties’” as evidenced by the
    thoroughness of his decision. Resp’t’s Resp. to Pet’r’s Mot. for Review 10
    (quoting RCFC, App. B, Rule 8(b)(1)). Once the Special Master thoroughly
    considered the record, he was entitled to weigh the evidence and conclude that
    he was not persuaded by petitioner’s theory of the case.
    We agree that the Special Master was careful to consider all relevant
    evidence, particularly those pieces on which petitioner relied to support her
    case. The Special Master discussed the literature that Dr. McCabe cited to
    show that medical experts were considering whether there is a connection
    between SJIA and vaccination, and he found these articles to be equivocal.
    See Decision at *8. The Special Master reviewed the content of the Pinto
    study at length and concluded that Dr. Rose’s interpretation of the significance
    17
    of the study was more persuasive. Decision at *23-24. Additionally, the
    Special Master engaged each part of Dr. McCabe’s expert opinion in the
    analysis of his decision. The Special Master also considered relevant evidence
    and testimony provided by Dr. Rose. The fact that the Special Master found
    Dr. Rose’s expert opinion more persuasive in light of Dr. Rose’s testimony and
    scientific evidence is simply a function of the Special Master’s role as fact
    finder. So long as the Special Master considered the relevant evidence, and we
    conclude that he did, we cannot disturb his findings on this ground.
    II.    Whether petitioner’s burden of proof was erroneously elevated
    A.      Whether the Special Master required petitioner to
    provide epidemiological proof
    Petitioner asserts that the Special Master erred by requiring
    epidemiological proof of petitioner’s theory. See Cappizzano v. Sec’y of
    Health & Human Servs., 
    440 F.3d 1317
    , 1325 (Fed. Cir. 2006) (“[R]equiring
    either epidemiological studies, rechallenge, the presence of pathological
    markers or genetic disposition, or general acceptance in the scientific or
    medical communities to establish a logical sequence of cause and effect . . . .
    impermissibly raises a claimant’s burden.”). Petitioner acknowledges that,
    throughout the Special Master’s decision, he asserted that he was not requiring
    epidemiological proof. Nevertheless, petitioner alleges that, instead of
    accepting Dr. McCabe’s explanation for why there is an absence of
    epidemiological and animal studies connecting Gardasil and the development
    of SJIA, the Special Master turned to and placed “inordinate emphasis” on
    epidemiological studies provided by respondent that were not squarely on
    point. Pet’r’s Mot. for Review 25. In sum, petitioner believes that the Special
    Master de facto required epidemiological evidence by pointing to the Chao
    article, which did not find any statistically relevant increase in the development
    of JRA following vaccination with Gardasil, and the Verstraeten article, which
    involved a different HPV vaccine, a different adjuvant, and did not target SJIA
    within the studied pool of individuals.
    Respondent argues that the Special Master did not raise the burden of
    proof. Rather, throughout his decision, the Special Master maintained that
    petitioner must prove her case by a preponderance of the evidence. See, e.g.,
    Decision at *18, *20, *28. Respondent states, and we agree, that under the
    preponderance of the evidence standard, simply positing a theory is not
    enough. Petitioner must provide a theory that is persuasive. See W.C., 704
    18
    F.3d at 1356.
    The Special Master has discretion to assess the reliability of expert
    testimony when weighing the persuasiveness of the evidence. Moberly, 
    592 F.3d at 1325
    . While the special master may not require epidemiological proof
    of petitioner’s theory, Cappizzano, 
    440 F.3d at 1325
    , he may evaluate
    contradictory evidence provided by respondent, Stone v. Sec’y of Health &
    Human Servs., 
    676 F.3d 1373
    , 1379-80, reh’g en banc denied, 
    690 F.3d 1380
    (Fed. Cir. 2012), cert. denied, 
    133 S. Ct. 2022
     (2013), and he may consider the
    presence or absence of peer reviewed scientific studies in the context of
    applying the Daubert framework for analyzing whether an expert’s theory is
    persuasive, Terran, 
    195 F.3d at 1316
     (upholding the special master’s approach
    of “using Daubert’s questions as a tool or framework for conducting the
    inquiry into the reliability of the evidence”); see Cedillo v. Sec’y of Health &
    Human Servs., 
    617 F.3d 1328
    , 1339 n.3 (Fed. Cir. 2010) (listing the case law
    in which the Court of Appeals for the Federal Circuit upheld the special
    master’s application of the Daubert factors).
    In this case, the Special Master considered epidemiological and other
    medical articles in the context of assessing the persuasiveness of the expert
    opinions using the first Daubert factor, which is whether the theory has been
    or can be tested. See 
    509 U.S. at 593
    . Throughout his analysis the Special
    Master considered the evidence presented by both experts. After considering
    the lack of animal studies, the articles that posited about a connection between
    SJIA and vaccination, and the studies that showed no worsening of symptoms
    in subjects with JIA and SJIA after receiving the MMR or the meningococcal
    C vaccine, the Special Master found that the latter evidence was more
    persuasive than the former and, therefore, this Daubert factor was either
    neutral or balanced against petitioner. While the Special Master may not
    require petitioner to prove his case with epidemiological studies, that does not
    mean that scientific evidence that tends to contradict petitioner’s theory must
    be ignored. The Special Master was squarely within his role as a fact-finder
    when he weighed the evidence presented to him. Because we are not tasked
    with reweighing the evidence, and the Special Master’s conclusion about the
    first Daubert factor was neither arbitrary nor capricious, we find no error. See
    Hulbert v. Sec’y of Health & Human Servs., 
    49 Fed. Cl. 485
    , 490 (2001), aff’d,
    35 F. App’x 899 (Fed. Cir. 2002) (deferring to the Special Master’s
    determination that the petitioner’s expert did not present an opinion that was
    as credible as the opinion given by the respondent’s expert when analyzed
    under the Daubert framework).
    19
    B.     Whether the Special Master impermissibly held against
    petitioner the fact that Dr. McCabe’s theory had not been
    published or peer reviewed
    Petitioner asserts the Special Master heightened her burden to
    something close to scientific certainty by holding against her the fact that Dr.
    McCabe’s theory had not been published and subject to peer review. Rather,
    plaintiff claims that she met her burden of preponderant evidence by
    presenting a theory that was in line with published and peer reviewed scientific
    literature.
    Respondent responds that it was permissible for the Special Master to
    ask whether Dr. McCabe’s theory had been published and subject to peer
    review because it is the second factor of the Daubert framework for assessing
    the reliability of an expert opinion. See 
    509 U.S. at 593
    . While we agree that
    it would be problematic if the Special Master had required petitioner uniquely
    to present a theory that had been tested and peer reviewed, that is not what
    happened in this case. The Special Master sought indicia of reliability through
    the use of the Daubert framework, and he noted that, “until [V]’s case, there
    was not even one case report published in the medical journals showing even
    a temporal sequence in which a Gardasil vaccination preceded sJIA.”
    Decision at *23 (citation omitted). The Special Master did not end his analysis
    of the second Daubert factor there, however. He proceeded to consider the
    peer reviewed medical evidence presented by petitioner and, after weighing it,
    concluded, “the evidence relating to peer review and publication does not
    assist in finding that Dr. McCabe’s theory is probable.” Decision at *24. The
    Special Master’s finding was not arbitrary or capricious, and it did not
    impermissibly raise petitioner’s burden because it occurred within a larger
    framework and was not the Special Master’s sole reason for concluding that
    petitioner’s theory was unpersuasive.
    C.     Whether it was in error and raised petitioner’s burden
    when the Special Master considered if rheumatologists
    generally accept Dr. McCabe’s theory
    When the Special Master inquired about whether rheumatologist
    generally accept the theory that Gardasil can cause SJIA, petitioner claims that
    he impermissibly raised her burden by requiring a theory that is generally
    accepted within the scientific community. Petitioner cites Graves v. Secretary
    20
    of Health and Human Services, 
    101 Fed. Cl. 310
    , 323 (2011) (reciting that
    general acceptance of the theory within the medical community is not
    required). According to petitioner, the Special Master arbitrarily and
    capriciously relied on Dr. Rose’s statement that he did not recall hearing
    discussion amongst his colleagues about Gardasil causing SJIA.
    Respondent contends, and we agree, that the Special Master’s inquiry
    into whether there is general acceptance of Dr. McCabe’s theory within the
    scientific community is permissible as part of the Daubert analysis. See 
    509 U.S. at 594
    . In his analysis of this factor, the Special Master noted that
    petitioner provided articles, such as Berent Prakken et al., Juvenile idiopathic
    arthritis, 377 Lancet 2138, 2141 (2011), that showed that the scientific
    community was hypothesizing that vaccinations or infections might trigger
    SJIA. Decision at *24. Also, the Special Master noted that Dr. Rose testified
    that pediatric rheumatologists did not accept the theory that Gardasil can cause
    SJIA and that the general practice of pediatric rheumatologists is to
    recommend that their patients receive all vaccinations except those that contain
    a live virus. As between these indications of what the relevant medical
    community believes about a connection between Gardasil and SJIA, the
    Special Master found that the relevant scientific community does not generally
    accept Dr. McCabe’s theory. This inquiry, as part of the Daubert framework,
    did not impermissibly raise petitioner’s burden of proof
    III.   Whether the Special Master misinterpreted the Pinto article
    Petitioner asserts that the Special Master’s findings regarding the Pinto
    study were contrary to the evidence. First, petitioner alleges that the Special
    Master was confused in thinking that the Pinto study involved a live strand of
    HPV. Petitioner points out that there is no evidence of a live human
    papillomavirus being involved in either V’s case or in the Pinto study. The
    Special Master’s statement regarding the live human papillomavirus appeared
    in the context of the following paragraph in the Special Master’s decision:
    Despite contrary testimony from Dr. McCabe . . . , Dr.
    Rose’s focus on the media column is logical. The blood in the
    media encountered the L1 virus-like particle only in the context
    of the three doses of vaccination. This pattern resembles what
    happened to [V] in the sense that no medical record suggests
    that she was exposed to a living strand of the human
    papillomavirus. If [V] encountered the human papillomavirus
    21
    after the vaccination, the Pinto article predicts that she would
    produce a robust immune response like the ones reported for 10
    µg and 1.0 µg of the virus-like particle.
    Decision at *23. This paragraph, when considered with the Special Master’s
    earlier description of the Pinto study, Decision at *4, shows that the Special
    Master understood that only VLP was used in the Pinto study. The Special
    Master’s comparison of the reaction of the blood samples when stimulated
    with VLP to show how the body would react to a natural HPV infection was
    made to illustrate Dr. Rose’s opinion that a robust cytokine response would be
    expected in response to stimulation. However, the distinction in this case is
    that V never experienced a stimulant such as a live human papillomavirus or
    a concentrated dose of VLP as was administered in the Pinto study. This is the
    reason why Dr. Rose thought that the media group in the Pinto study was more
    relevant than the stimulated groups. The Special Master’s agreement with
    that analysis was neither erroneous or illogical.
    Second, petitioner argues that the Special Master’s reliance on Dr.
    Rose’s interpretation of the Pinto study was arbitrary and capricious because
    Dr. Rose is not an immunologist and has not conducted research involving
    vaccines or pro-inflammatory cytokines. Dr. Rose was accepted as an expert
    in pediatric rheumatology and, as such, was qualified to opine about medical
    studies. The Special Master did not exclude Dr. McCabe’s interpretation of
    the Pinto study, but instead found Dr. Rose’s interpretation to be more reliable.
    Moberly, 
    592 F.3d at 1325-26
     (“Assessments as to the reliability of expert
    testimony often turn on credibility determinations, particularly in cases . . .
    where there is little supporting evidence for the expert’s opinion.”).
    Respondent asserts, and we agree, that, in light of all of the evidence, the
    Special Master’s reliance on Dr. Rose’s interpretation of the significance of
    the Pinto study was within his discretion as the fact-finder.
    IV.    Whether the Special Master arbitrarily and capriciously weighed
    the evidence against petitioner
    A.      Petitioner provided scientific support for her theory,
    which the Special Master arbitrarily dismissed
    Petitioner claims that the Special Master erroneously dismissed
    scientific support for petitioner’s theory. Specifically, in the Special Master’s
    Althen prong-one analysis, he “neither cites not considers the Mellins,
    22
    Roghany, Prakken, or Emeny articles.”15 Pet’r’s Mot. for Review 20.
    Petitioner argues that, instead of affording proper weight to the
    aforementioned studies provided by petitioner which were relevant, from
    respected journals, and peer-reviewed, the Special Master arbitrarily favored
    analogous, but off-topic, studies authored by Heijstek and Zonneveld-
    Huijssoon. Petitioner distinguishes the Heijstek and Zonneveld-Huijssoon
    studies because they involved the meningococcal C and the MMR vaccines,
    which lack the potency of Gardasil, and involved patients who had already
    developed SJIA and may have been taking pharmaceuticals to control the
    disease. Additionally, Dr. McCabe testified that he would expect the
    meningococcal C vaccine, which is a vaccine against a bacterial infection, to
    elicit a different cytokine response than the HPV vaccine, which immunizes
    against a virus. Hr’g Tr. 183-84. These differences between the Heijstek and
    Zonneveld-Huijssoon studies and the facts of this case, according to petitioner,
    make the Special Master’s reliance on them arbitrary and capricious.
    By contrast, respondent argues that the Special Master considered the
    Prakken, Mellins, Roghany, and Emeny articles but found that they did not
    support petitioner’s theory. While the Special Master did not evaluate each of
    these articles specifically in the context of prong one, he did reference them
    throughout his decision and found that the statements that petitioner relied on
    from these articles were ambiguous. In his decision, the Special Master
    described the scientific support that petitioner gleaned from the Prakken,
    Mellins, and Roghany articles and found it to be unpersuasive due to the
    equivocation in the findings. Decision at *8-9, *13, *16, *22, *24. While the
    Special Master only briefly mentioned the Emeny article in his decision, he did
    write that, “[a]t the hearing, relatively little attention was paid to the García-
    Piñeres article, Emeny article, or the Evans article because Dr. McCabe and
    Dr. Rose primarily discussed an article by Pinto.” Decision at *3. As fact-
    finder, it is within the province of the Special Master to weigh the evidence
    and determine whether it is reliable. He plainly was aware of all the articles
    and was not obligated to unpack them in detail. His treatment of the Prakken,
    Mellins, Roghany, and Emeny articles was not arbitrary or capricious.
    15
    The “Emeny” article referred to in the quotation above is Rebecca T.
    Emeny et al., Cellular Immune Responses to Human Papillomavirus (HPV)–16
    L1 in Health Volunteers Immunized with Recombinant HPV-16 L1 Virus-Like
    Particles, 188 J. Infectious Diseases 327, 336 (2003) (hereinafter “Emeny”).
    23
    B.     Whether the Special Master arbitrarily and capriciously
    disregarded Dr. McCabe’s testimony
    According to petitioner, the Special Master erred by disregarding Dr.
    McCabe’s testimony on prong two because he does not treat patients.
    Petitioner asserts that Dr. McCabe is qualified to testify about causation even
    though he would not be qualified to testify about treatment. Petitioner also
    opines that, while Dr. McCabe was uniquely qualified to testify about the
    causal connection between Gardasil and SJIA based on his research as an
    immunologist, Dr. Rose has never focused on causation but instead specializes
    in treating children with SJIA.
    Respondent replies that the Special Master fully considered Dr.
    McCabe’s testimony, including Dr. McCabe’s testimony concerning whether
    V’s flare following the third Gardasil dose was indicative of specific
    causation. Respondent points out that it is the Special Master’s prerogative
    under the law to examine the qualifications and expertise of the witnesses
    when weighing their opinions, citing Locane v. Secretary of Health and
    Human Services, 
    685 F.3d 1375
    , 1380 (Fed. Cir. 2012). Here, the Special
    Master found more reliable Dr. Rose’s opinion that V’s vaccination with
    Gardasil and development of SJIA were unrelated events. This finding is
    sound under the law and was not arbitrary or capricious given the divergent
    expert opinions.
    Finally, petitioner contends that the Special Master erred by
    disregarding Dr. McCabe’s testimony about the temporal relationship between
    vaccination and disease. Dr. McCabe explained that a cytokine response may
    take months to cycle through a period of amplification to eventually manifest
    as SJIA. Dr. McCabe testified that development of SJIA within seven months
    of vaccination therefore would be a medically appropriate period for causation
    because that is the time period when the immune system works to create
    antibodies against HPV in response to the HPV vaccine. See Decision at *27.
    Timing was thus indicative of causation in V’s case, according to Dr. McCabe,
    because she developed SJIA within four months of her first dose and two
    months of the second dose.
    The Special Master was not persuaded by Dr. McCabe’s explanation of
    the amplification process. “[S]pecifically, Dr. McCabe did not explain why
    the immune system’s production of cytokines would be amplified for weeks
    and months without a stimulant being present.” Decision at *28. The Special
    24
    Master found that Dr. McCabe failed to explain how a seven month period is
    appropriate for causation based on a theory involving the cytokine response
    when both experts agree the response is almost immediate to an antigen or
    trigger. The Special Master wrote that “[t]he body’s rapid cytokine response
    appears inconsistent with Dr. McCabe’s assertion that the onset of disease
    could take many months.” Decision at *28.
    Respondent argues that the Special Master was entitled to find
    persuasive Dr. Rose’s opinion regarding timing, which was that the medically
    appropriate period for causation should be short if the cause is cytokine
    related. Dr. Rose’s opinion was not the only scientific evidence that suggested
    a shorter window for causation than Dr. McCabe proposed. The Special
    Master also drew from data in the Pinto study showing increased cytokines in
    response to stimulation and compared it to data that demonstrated a low and
    consistent level of cytokines in the absence of stimulation. The Special Master
    found that “[t]he Pinto experiment [] undermines the cohesiveness of Dr.
    McCabe’s theory, particularly in regard to timing both for onset of symptoms
    and duration of symptoms.” Decision at *23.
    After considering the evidence and testimony from both experts, the
    Special Master asserted that a finding on Althen prong-three was not necessary
    because petitioner had failed to establish prong-one. Nevertheless, the Special
    Master noted the following: “In the absence of evidence, it is difficult to find
    that [petitioner] has met her burden of proof. Even two months is probably too
    long an interval for a cytokine-driven reaction.” Decision at *28. We will not
    disturb this finding because it was not arbitrary or capricious in light of the
    evidence.
    CONCLUSION
    It is not our role to “reweigh the factual evidence, assess whether the
    special master correctly evaluated the evidence, or examine the probative value
    of the evidence or the credibility of the witnesses.” Porter, 
    663 F.3d at 1249
    .
    Because the Special Master’s decision was not arbitrary, capricious, or
    otherwise not in accordance with the law, we affirm his decision. For the
    reasons set forth above, we deny petitioner’s motion for review. The clerk is
    directed to enter judgment accordingly. No costs.
    25
    s/Eric G. Bruggink
    ERIC G. BRUGGINK
    Judge
    26