Expert Witness Profiler

Category: Pediatrics Expert Witness

  • Nutrition Expert Not Allowed to Opine on FTC Compliance

    Nutrition Expert Not Allowed to Opine on FTC Compliance

    This putative class action involves claims that a manufacturer falsely marketed its pediatric nutrition beverage as helping children grow taller. Joanne Noriega sued Abbott Laboratories (“Abbott”), claiming that the packaging and marketing of its beverage, PediaSure Grow & Gain (“PediaSure”), has thus misled consumers. Noriega claimed that she purchased PediaSure for her grandson based on Abbott’s representation that PediaSure is “Clinically Proven to Help Kids Grow (the “challenged statement”). That claim, she alleged, allowed Abbott to charge a price premium for the product.

    Abbott filed motions to exclude the testimony of Dr. Gita Johar (as to consumer perception of the challenged statement), Dr. Daniel Hoffman (as to scientific studies of PediaSure’s effects on growth), and Dr. William Ingersoll (as to the price premium attributable to the challenged statement). Noriega filed motions to exclude the testimony of Dr. Ran Kivetz (as to the materiality of the challenged statement) and Dr. Melvin Heyman (as to scientific studies).

    Marketing Expert Witnesses

    Dr. Gita V. Johar is a professor at Columbia Business School, where she has taught classes on marketing, branding, and research methods since 1992. She earned her PhD in marketing from the New York University School of Business. She has served as a fellow and president of the Society for Consumer Psychology, and as an editor of the Journal of Consumer Research, Journal of Marketing, and Journal of Consumer Psychology. Johar has published papers on topics including deceptive advertising, corrective advertising, refutation of false beliefs formed based on advertisements, effectiveness of disclosures in advertising, and inferences and false beliefs based on advertising claims.

    Get the full story on challenges to Gita Johar’s expert opinions and testimony with an in-depth Challenge Study.

    Dr. Ran Kivetz is a marketing professor at Columbia Business School, where he teaches courses related to marketing strategy, consumer acquisition and retention, and behavioral economics. He earned his PhD in business from Stanford Graduate School of Business and a master’s degree in psychology from Stanford University. His research focuses on buyers’ purchasing behavior, survey design, and the effect of product characteristics on purchase decisions. He has published numerous articles on topics related to consumer behavior and decision-making.

    Kivetz has achieved recognition for his contributions to consumer research, including from the Journal of Marketing Research and Society of Consumer Psychology. He serves on the editorial boards of three journals, evaluating marketing research surveys for publication.

    Want to know more about the challenges Ran Kivetz has faced? Get the full details with our Challenge Study report.

    Nutrition Expert Witness

    Dr. Daniel J. Hoffman is a professor in the Department of Nutritional Sciences at Rutgers University, where he has taught for the last 25 years. He earned his PhD in human nutrition from Tufts University, a certificate in epidemiology from the World Health Organization, and a master’s degree in cell biology from The Catholic University of America. Between 2012 and 2022, in addition to teaching, he served as director of the Center for Childhood Nutrition Research at the New Jersey Institute for Food, Nutrition and Health.

    Discover more cases with Daniel Hoffman as an expert witness by ordering his comprehensive Expert Witness Profile report.

    Economics Expert Witness

    Dr. William Robert Ingersoll is an associate professor and chair of business and entrepreneurship at Azusa Pacific University, where he teaches courses in industrial organization, econometrics, and microeconomic theory. He earned a PhD and master’s degree in economics from the University of Arizona. He represents that he has testified as an economic damages expert in a variety of state and federal cases.

    Get the full story on challenges to William Ingersoll’s expert opinions and testimony with an in-depth Challenge Study.

    Pediatrics Expert Witness

    Dr. Melvin Bernard Heyman is a professor in the Department of Pediatrics at the University of California, San Francisco School of Medicine (“UCSF”). He earned his medical degree from the University of California, Los Angeles (“UCLA”); completed a residency in pediatrics at Los Angeles County-University of Southern California Medical Center; and completed a fellowship at UCLA in pediatric gastroenterology and nutrition. Since 1981, he has worked in pediatric health and medicine, conducting thousands of clinical visits during his career, many of which addressed children’s nutritional needs. Between 1990 and 2016, Heyman served as chief of UCSF’s pediatric gastroenterology division and organized nutritional support services for pediatric patients. He has held leadership roles on local and national committees, including the American Board of Pediatrics and the American Academy of Pediatrics Committee on Nutrition, and has served as editor-in-chief of the Journal of Pediatric Gastroenterology and Nutrition.

    Gain a comprehensive understanding of Melvin Heyman’s qualifications and casework history with his Expert Witness Profile report.

    Discussion by the Court

    Gita Johar

    Johar was retained by Noriega to opine on whether the PediaSure label and commercials would lead a reasonable consumer to believe that the product is clinically proven to help kids grow in height.

    Johar’s expert report assesses whether the PediaSure label and commercials would lead a reasonable consumer to believe that the product is clinically proven to help kids grow in height. Based on her assessment of the PediaSure label and commercials, Johar opined that Abbott has misled consumers to believe that PediaSure has been clinically proven to help kids grow in height. 

    a. Reliability of Johar’s Methodology

    Abbott argued that Johar’s methodology is unreliable because she did not undertake an empirical consumer survey, which it contended departed both from “accepted practice” in the field and from Johar’s own academic research practices.

    The Court held that Johar’s education and experience, taken together with the relevant academic literature on which she relied, supplied an adequate basis for the testimony she proposed to give.

    Abbott noted that Johar lacked specific expertise as to children’s nutrition drinks. Given her extensive experience in consumer product marketing, however, that fact, though fair game for cross-examination, did not support precluding her as unqualified to testify here.

    b. Relevance of Johar’s Consumer Perception Opinions

    Abbott argued that Johar’s testimony would not be helpful to the jury because “her opinions are purely subjective.”

    The Court found that Johar’s testimony would be helpful to the jury. Notwithstanding Abbott’s portrait of her testimony, she did not propose to set out her personal beliefs, as a consumer, about the meaning of the challenged statement on the label. Instead, she proposed to opine, as a marketing professor, based on her experience and research, about how a reasonable consumer would view and process the challenged statement in the context of PediaSure’s packaging.

    Daniel Hoffman

    Hoffman was retained by Noriega as a nutrition and growth expert to opine as to whether PediaSure has been—as the challenged statement represents—clinically proven to help kids grow.

    Hoffman addressed Abbott’s claims substantiation guidance (“CSG”)—an internal manual that addresses health benefit claims, the evidence necessary to substantiate such claims, and the claims development process. He opined that the CSG “sets mandates to be followed” by Abbott and is not “merely aspirational.”

    a. Opinions About the CSG

    Abbott sought to preclude Hoffman’s testimony about the CSG on the grounds that he is unqualified to opine on an internal Abbott document and cannot properly opine on Abbott’s state of mind.

    To begin with, the Court found that Hoffman is not an expert in marketing, claims substantiation, or Abbott’s internal practices. When asked at his deposition what qualified him to interpret the CSG, he answered his “research education.”

    Moreover, the CSG’s guidance, if relevant at trial, would not be “beyond the ken of the average juror” to grasp.

    Finally, Hoffman’s proposed opinion testimony that Abbott failed to comply with the CSG’s ostensibly mandatory guidance is not the province of an expert.

    b. Reliability of Hoffman’s Analysis of Abbott’s Studies

    Abbott argued that Hoffman employed an unreliable methodology in finding Abbott’s studies of PediaSure unsound.

    A fair-minded review of Hoffman’s report supported the reliability of his methodology in evaluating Abbott’s studies. He drew upon his experience (both as a researcher in the field of pediatric growth and nutrition, and as an editor of scientific journals) and academic articles about standards applicable to clinical studies, randomized trials, and medical research involving human subjects.

    c. Relevance of Hoffman’s Opinions on Abbott’s Studies

    Abbott next argued that Hoffman’s opinions as to the scientific rigor of Abbott’s studies are irrelevant because they are based on “academic publication standards.”

    However, the Court found that Hoffman’s report sets out standards that must be satisfied for a study to be considered “transparent,” “objective,”  “scientifically vetted,” “scientifically rigorous,” and “unbiased.”

    Few of the 36 journal articles on which Hoffman relied in support of those standards appear to relate to “academic publishing,” and even those appear to be generally applicable.

    That Hoffman’s analysis of Abbott’s studies tracks analyses he conducted in his editorial roles is no impediment to the admissibility his testimony.

    d. Opinions Not Stated in Expert Report

    Abbott sought to preclude Hoffman’s opinions related to (1) Abbott’s compliance with Federal Trade Commission (“FTC”) health claims guidance and (2) how a reasonable consumer would interpret the challenged statement.

    It was in his deposition that Hoffman articulated for the first time his opinions about Abbott’s compliance with FTC guidance and consumers’ perceptions of the challenged statement.

    Noriega did not contend that these opinions were disclosed earlier or justify the failure to do so. The Court thus cannot find their non-disclosure substantially justified.

    Moreover, Hoffman’s education and experience is in “nutritional sciences and growth,” he is therefore unqualified to opine on FTC compliance or consumer perception.

    Because Noriega failed to timely disclose Hoffman’s opinions on FTC compliance and consumer perception, and because they are independently inadmissible, the Court excluded such testimony.

    William Ingersoll

    Noriega’s expert, Ingersoll, proposed to opine that: (1) products bearing the label “Clinically Proven to Help Kids Grow” are on average “more favorably viewed” than ones that state, “Helps Kids Grow”, or that make no statement about growth; and (2) consumers are willing to pay more—in the amounts above—for the product bearing the challenged statement than the growth-only statement or no statement.

    a. Relevance of Ingersoll’s Survey Results

    Abbott argued that Ingersoll’s survey failed to calculate a price premium keyed to Noriega’s theory of consumer deception.

    Because Noriega’s theory is that the challenged statement misled consumers to believe that PediaSure promotes height growth, Abbott argued, the survey, to be helpful, needed to “isolate a price premium traceable to Abbott’s purported misrepresentation about height.”

    Ingersoll’s survey tested the premiums attributable to the label statements, “Clinically Proven to Help Kids Grow,” and “Helps Kids Grow.” But on their faces, those statements do not exclusively concern height. Their references to growth can also—or alternatively—be read to encompass other forms of growth (e.g., weight, body composition, and/or muscular development).

    As a result, the Court held that Ingersoll’s survey aimed at quantifying price-premium damages did not “fit” Noriega’s theory of liability. 

    Ingersoll could have tested the price premium traceable to a hypothetical height-growth-specific statement. Or he could have tested the value that respondents place on various promised health benefits (e.g., height growth compared to weight gain). Either approach might have enabled him to isolate the price associated with the alleged misrepresentation about height. Ingersoll’s failure to do so resulted in a broad conclusion—that consumers are willing to pay more when PediaSure contains the challenged statement—that is not tailored to Noriega’s theory of the case nor helpful to a jury tasked with isolating the damages (via a price premium theory) attributable to a misrepresentation about height. This flaw is sufficiently fundamental to require exclusion of his proposed testimony.

    b. Reliability of Ingersoll’s Survey Methodology

    Abbott argued that Ingersoll’s conclusions are separately irrelevant because the survey he used showed a “truncated version of the challenged statement” which excluded the footnote disclaimer.

    The Court found that Ingersoll’s failure to test the disclaimer undermined the reliability of his conclusions as to the price premium attributable to the challenged statement. As Abbott noted, the disclaimer supplied context for the statement’s claim of clinical proof: a person who read and understood the disclaimer could be alerted to the fact that the evidence of PediaSure’s growth benefits “came not in studies of all children but rather those who were ‘at risk of malnutrition.’” 

    More broadly, Ingersoll’s election not to address the disclaimer in his report is strong evidence of motivated reasoning—that his analysis was not “reliable at every step,” but instead was result-driven.

    Ran Kivetz

    Kivetz was retained by Abbott to assess whether the challenged statement, as modified by the disclaimer, was a driver of consumers’ decisions to purchase and/or pay a price premium for PediaSure. 

    Kivetz conducted an empirical consumer materiality survey to test the effect of the challenged statement on consumers’ likelihood of purchasing and willingness to pay for PediaSure, and to ascertain the reasons and motivations driving consumers’ purchase of the products.

    He drew two conclusions based on the survey’s results. First, Kivetz concluded that the challenged statement did not drive consumers to purchase PediaSure. Second, Kivetz concluded that consumers are not willing to pay more for PediaSure when the challenged statement is present compared to when it is absent.

    a. Reliability of Kivetz’s Survey Design

    Noriega argued that, for three reasons, the design of Kivetz’s consumer survey was unreliable.

    First, Noriega argued that Kivetz erred in conducting a between-group, rather than within-group, study. Even if a within-group study would have been more effective for assessing materiality, the Court held that Kivetz’s decision to conduct a between-group study did not render his survey unreliable.

    Second, Noriega claimed that Kivetz’s study “suffers from . . . the ceiling effect.” Because approximately 90% of individuals in both the test and control groups stated that they were probably or definitely likely to purchase PediaSure, Noriega argues, there was “no room” to perceive the effect of the challenged statement.  That his survey might have been better designed, however, does not render it unreliable.

    Third, Noriega argued that Kivetz’s use of open-ended questions “produced incorrect and unreliable data.”

    The survey asked consumers why they were definitely/probably likely or unlikely to buy the product, and instructed respondents to “be specific and include details.” It then asked for “any other reason or reasons” for their purchase likelihood, and again instructed them to be specific. Respondents were thus prompted to provide a fulsome explanation for their purchase decision—not just the first reason that occurred to them. The survey also asked respondents closed-ended questions in addition to the two open-ended questions. Respondents were asked about their purchase likelihood (which required choosing between six answer choices) and willingness to pay (which required a numeric response). Accordingly, the questions here do not come close to requiring exclusion of the survey.

    b. Reliability of Survey Coding

    Noriega next argued that Kivetz’s methodology for coding the survey responses was unreliable, and that the responses did not support his conclusions. She argued that Kivetz failed to provide instructions to anonymous assistants, who made “highly subjective” coding decisions, and to keep data that would allow Noriega to determine how each response was coded. But Kivetz provided the coders with a “coding frame,” which contained a list of specific categories in which the responses could be classified. And Noriega did not dispute that Abbott produced the raw survey data, which was also attached to Kivetz’s report. Noriega accordingly could have, based on the raw data, coding frame, and results, reconstructed how responses were coded. The Court found her objections on this basis unavailing.

    c. Opinions Based on Caselaw

    Noriega argued that Kivetz’s testimony should be excluded insofar as it “offers legal conclusions.” Kivetz references caselaw once in his report.

    In support of his statement that the survey he conducted is “routinely used in academic, industry, and litigation settings,” he cited cases that accepted his consumer surveys and found that they “conclusively showed that the challenged claims were not material.” It should be noted that an expert’s testimony on issues of law is inadmissible.

    Melvin Heyman

    Abbott’s expert Heyman opined that there is ample clinical support for a claim that PediaSure helps kids grow, including in both height and weight.

    a. Qualifications to Opine on Height Growth

    Noriega argued that Heyman is unqualified to opine on pediatric height growth because he lacked specialized training or experience in the field.

    Although Heyman did not appear to have expertise in pediatric height growth specifically, that does not render his qualifications inadequate. Courts admit testimony of experts who have “educational and experiential qualifications in a general field closely related to the subject matter in question,” but lack expertise in “the specialized areas that are directly pertinent.”

    b. Reliability of Heyman’s Methodology

    Noriega argued that Heyman’s analysis is unreliable due to a lack of textual support for his assessment of Abbott’s studies. The Court held that Heyman’s testimony is reliable because he has shown how his experience led to his conclusion. Although Heyman’s failure to cite relevant authority might undermine the strength of his conclusions, it does not invalidate them.

    Second, Noriega argued that Heyman’s analysis is unreliable because he failed to rely on the CSG, which constitutes “considerable contradictory evidence.” As noted, however, the CSG is an internal Abbott document that supplies guidance for substantiating marketing claims. It was unnecessary for Heyman to consider it in analyzing the findings of Abbott’s studies, or whether the studies were scientifically rigorous.

    Heyman also addressed the AL-48 study, which he opined was a “scientifically rigorous clinical study that affirms . . . the height-related findings of prior PediaSure studies.” Noriega argued that Heyman’s analysis is unreliable because it is premised on the AL-48 study, which is “unfinished, unwritten, and unpublished.”

    The Court found the AL-48 study was not relevant, because it was completed after the time period on which Noriega’s claims are based (and after the proposed class period). Accordingly, the Court excluded Heyman’s testimony insofar as it references or relies on that study.

    c. Relevance of Opinions About Non-Height Growth

    Noriega argued that Heyman’s testimony would be unhelpful to jurors because he “avoids opining on height growth specifically,” instead addressing other forms of growth that are “wholly irrelevant” to Noriega’s claims.

    The Court found this argument unavailing because Heyman did opine on height growth. His conclusions as to the height findings of Abbott’s studies are central to his proposed testimony.

    d. Relevance of Opinions About L.V ‘s Medical Records

    Noriega argued that Heyman’s testimony related to L.V.’s medical records is irrelevant. The Court agreed.

    Even taking as true Heyman’s assessment that L.V. grew while he consumed PediaSure, such would not make it more likely that PediaSure helps kids grow. There are myriad reasons why L.V. might have grown during the relevant period, such as his genetics, age, diet, sleep, and physical activity. Heyman did not opine that PediaSure caused L.V.’s height growth, nor could he responsibly do so.

    If L.V. grew during the relevant period, that fact would be fair game to use to impeach that aspect of Noriega’s testimony. But a medical expert is not necessary to establish it. L.V.’s medical records, which reflect the weight and height recorded at his appointments in July 2021 and March 2023, are comprehensible to a layperson. Abbott has not contended that expert testimony is needed to decode them on this point. Accordingly, such testimony would be improper.

    Held

    • The Court denied in full Abbott’s motion to exclude Dr. Gita Johar’s testimony.
    • The Court granted in part and denied in part Abbott’s motion to exclude Dr. Daniel Hoffman’s testimony.
    • The Court granted in full Abbott’s motion to exclude Dr. William Ingersoll’s testimony.
    • The Court granted in part and denied in part Noriega’s motion to exclude Dr. Ran Kivetz’s testimony.
    • The Court granted in part and denied in part Noriega’s motion to exclude Dr. Melvin Heyman’s testimony. 

    Key Takeaway

    Trial courts serve as gatekeepers, responsible for ‘ensuring that an expert’s testimony both rests on a reliable foundation and is relevant to the task at hand.

    Whether a witness is qualified as an expert is a threshold question that precedes the Court’s relevance and reliability inquiries. It is critical that an expert’s analysis be reliable at every step. To ensure relevance, the Court must assess whether the expert’s testimony fits the facts of the case.

    Case Details:

    Case Caption: Noriega V. Abbott Laboratories
    Docket Number: 1:23cv4014
    Court Name: United States District Court, New York Southern
    Order Date: June 04, 2026
  • Pediatrics Expert’s Opinion Regarding a Target 95% Vaccination Rate Met the Daubert Bar

    Pediatrics Expert’s Opinion Regarding a Target 95% Vaccination Rate Met the Daubert Bar

    On July 22, 2022, Dr. Gregory Fox, individually and as parent of C.F., and Rita Fox, individually and as parent of C.F. (jointly, the Plaintiffs), filed a lawsuit challenging the state of Maine’s public school vaccination requirements.

    Dr. Laura Blaisdell, a pediatrician with extensive qualifications in medicine and public health, was presented as an expert witness by Department of Education Commissioner Pender Makin. Fox’s challenge centered on Blaisdell’s opinion regarding a 95% vaccination rate target. He argued that her reliance on the R0 variable, which assumes a “totally susceptible” population, was unreliable and unsupported by scientific methodology when applied to the case’s specific facts. He claimed her assumption was erroneous because the population in question was only “partially susceptible”.

    Furthermore, Fox contested the scientific support for the 95% vaccination coverage goal, asserting that Blaisdell erred in inferring its necessity to protect susceptible individuals or halt disease transmission.

    Pediatrics Expert Witness

    Laura L. Blaisdell, MD, MPH, FAAP, CPE is a board-certified pediatrician, public health consultant, and researcher with expertise in vaccine hesitancy, infectious disease control, and camp medicine. She holds a Doctor of Medicine (MD) from the University of Minnesota Medical School and a Master of Public Health (MPH) from the University of Minnesota School of Public Health. She is also a Certified Physician Executive (CPE) and a Fellow of the American Academy of Pediatrics (FAAP).

    Blaisdell has served as an Attending Physician in the Department of Pediatrics at Maine Medical Center since 2008 and is an Assistant Professor at Tufts University School of Medicine. Her research and clinical work focus on vaccine decision-making, public health policy, and disease prevention in communal settings, particularly youth camps. She has been a key figure in vaccine advocacy and has contributed to legislative efforts to promote immunization policies.

    Want to know more about the challenges Laura Blaisdell has faced? Get the full details with our Challenge Study report. 

    Discussion by the Court

    Commissioner Makin countered that Fox conflated herd immunity threshold rates with public health vaccination targets for schools. They argued that Blaisdell’s use of R0 was a generally accepted practice for determining herd immunity thresholds.

    Regarding the 95% target, the Commissioner emphasized that it was a public health goal, not a herd immunity threshold, aligning with targets set by the United States Centers for Disease Control and Prevention (U.S. CDC) and the Maine Center for Disease Control and Prevention (Maine CDC). Blaisdell, in her deposition, clarified the distinction, stating that the 95% figure represents a public health recommendation for school vaccination levels.

    Analysis

    The Court acknowledged that Blaisdell’s use of R0 to calculate herd immunity thresholds was supported by scientific literature, including articles cited by both parties. While the use of this methodology in other scientific literature is not conclusive, it did demonstrate a measure of acceptance within the scientific community.

    The Court ruled that Fox’s challenge regarding the “partially susceptible” population goes to the weight and credibility of Blaisdell’s testimony, not its admissibility. The Court also recognized the distinction between herd immunity thresholds and public health vaccination goals.

    Blaisdell’s reliance on sources like the CDC and state health reports, as well as her clear explanation during deposition, provided sufficient support for the 95% target as a public health goal. Moreover, Blaisdell sufficiently distinguished herd immunity threshold calculations from the public health goal of 95% vaccination coverage. Therefore, challenges to the weight and credibility of the 95% goal did not prevent the testimony from being admissible.

    Held

    The Court dismissed without prejudice Gregory Fox’s motion to partially exclude the testimony of Dr. Laura Blaisdell.

    Key Takeaway:

    This case highlights the importance of distinguishing between different types of scientific targets, such as herd immunity thresholds and public health goals. It also demonstrates the Court’s role in evaluating the reliability and relevance of expert testimony under the Daubert standard. The Court’s decision emphasizes that challenges to the factual underpinnings of expert opinions primarily affect their weight and credibility, not necessarily their admissibility.

    Case Details:

    Case Caption: Fox Et Al V. Makin Et Al
    Docket Number: 2:22cv251
    Court: United States District Court, Maine
    Order Date: March 10, 2025
  • Court Admits Pediatrics Expert Witness’ Specific Causation Opinion Based on Differential Diagnosis

    Court Admits Pediatrics Expert Witness’ Specific Causation Opinion Based on Differential Diagnosis

    For over 10 years, Fisher-Price sold a product called the Rock ‘n Play Sleeper (RnP). The Plaintiff, Ameena Brown, argued that the defective design of the RnP was to blame because her infant son, A.B., had died from sleeping in it. The dangers of this inclined sleeper product were widely debated in this case.

    It all started when A.B.’s mother, Plaintiff Ameena Brown, was gifted a secondhand Rock ‘n Play for A.B. During naptime and overnight sleep, Ameena would place A.B. supine in the RnP, which she kept in the living room.

    On January 15, 2018, the day before A.B.’s death, there was nothing out of the ordinary about A.B.’s health or demeanor. At approximately 6:00 AM the next morning, Ameena awoke and went to check on A.B. A.B. was found dead in the Rock ‘n Play.

    Plaintiffs sought to introduce Darlene Calhoun‘s testimony to show: (1) the design of the RnP increased the risk of harm; (2) A.B. died from suffocation after rolling onto his side and pressing his face against the side of the RnP; (3) A.B. could have expected a normal life expectancy despite his premature birth; and (4) A.B. experienced conscious pain and suffering before death. Calhoun’s report also touches on the topic of rebreathing.

    Defendants contended Calhoun: (1) lacked the requisite qualifications to opine on cause of death; (2) had no basis to conclude the RnP’s design is defective aside from the opinion of other experts in this case; (3) bases her conclusions on “mere association” as opposed to “reliable scientific opinions;” and (4) relied on a theory of increased risk causation which is impermissible under Pennsylvania law.

    Pediatrics Expert Witness

    Darlene A. Vasbinder-Calhoun, D.O. is a retired Neonatalist-Perinatalist. She received her D.O. degree in 1991 from the Ohio University College of Osteopathic Medicine. She is board certified in pediatrics. Calhoun describes her experience as “clinical practice in Neonatal-Perinatal Medicine,” working in Neonatal intensive care units, and conducting academic research.

    Want to know more about the challenges Darlene Calhoun has faced? Get the full details with our Challenge Study report. 

    Discussion by the Court

    During her deposition, Calhoun stated “[m]y opinion is that [A.B.] died from suffocation related to the compression of his mouth and nose against the fabric of the Rock ‘n Play Sleeper.”

    Calhoun formed that opinion based on her review of A.B.’s medical records, the witness statements of A.B.’s mother, various studies Calhoun cited in her report, and her own training and experience.

    Calhoun May Not Offer General Causation Testimony

    Defendants asserted that Calhoun does not qualify as a biomechanical engineer, or a forensic pathologist, and so cannot opine as to design flaws or cause of death.  Further, Defendants contended that Calhoun relies upon “mere association”—the fact A.B. was found deceased in the device—rather than reliable scientific opinions, testing, or data demonstrating causation.

    Calhoun’s general causation opinion “is simply saying that here the Rock ‘n Play can cause death.” The Court held that a review of Calhoun’s report as it pertains to general causation shows little analysis based upon her own expertise. Although she bases her general causation opinion on the type of “information reasonably relied upon by experts in the particular field,” she does not add any of her own context as to how the design of the RnP can cause death.

    Defendants further contended Calhoun “does not have any experience related to product safety testing” which would render her discussion of Fisher-Price’s testing procedures and recall decisions admissible. The Court held that Calhoun has never conducted tests on infant sleep products, and her discussion about whether Fisher-Price knew the RnP posed a threat to infants amounts to a recounting of alleged facts generated without her particularized skills and education. Admitting this testimony may also mislead the jury and would permit Calhoun to testify about recalls and test procedures of which she has no expertise to testify.

    Calhoun’s Specific Causation Testimony Is Admissible

    Though Calhoun did not formally label her opinion as the result of a differential diagnosis, Plaintiffs contended that is precisely the methodology Calhoun utilizes in her report. A differential diagnosis involves the doctor creating a list of possible causes of death, and then working through the medical records to exclude each of those potential causes until only one reasonable explanation remains.

    In her report, Calhoun considers as possible causes of death, and then excludes: Sudden Infant Death Syndrome; Gastroesophageal Reflux Disease; complications from A.B.’s Atrial Septal Defect; complications from A.B.’s Nasogastric Feeding Tube; and A.B.’s respiratory conditions. She also considered A.B.’s developmental age, his preference to turn to his right side, and the way he was found in the RnP the morning of his death.

    Calhoun provides her reasoning, based on her training and experience, for concluding that she can rule out the alternative causes of death she considered. She then concludes, based on those exclusions and the information available to her, that A.B. died of asphyxiation. Further, she concludes due to A.B.’s developmental delays that he would have been unable to roll onto his side, absent the design of the RnP facilitating his roll. Calhoun created a list of possible causes of A.B.’s death, and her report explains why she excluded each alternative.

    Defendants raise several specific issues with Calhoun’s methodology, but these issues, according to the Court, relate to the credibility of her opinion, not its admissibility.

    For instance, Defendants’ argument based on Calhoun’s inability to know exactly what transpired during the time between Brown placing A.B. in the RnP and his death amounts to an argument against the credibility of Calhoun’s diagnosis, but not its admissibility.

    Calhoun Cannot Rely On Increased Risk Of Harm To Establish Causation

    Defendants contended Calhoun impermissibly relied on an “increased risk” standard, which Pennsylvania law prohibits in product liability cases. Calhoun’s ultimate conclusion stated, “[i]t is my opinion that the design of the Rock ‘n Play Sleeper increased the risk of harm for and was the direct cause of [A.B.’s] asphyxiation, physical pain and suffering, and death.”

    After extensive argument, Defendants conceded their position with Plaintiffs as they “understood counsel to be acknowledging that they were not trying to substitute increased risk for proof of causation.” Here, Calhoun offered a basis for specific causation which goes beyond her reliance on increased risk. Moreover, Defendants have conceded that Plaintiffs are not attempting to substitute increased risk for causation. Accordingly, the Court held that Calhoun may not testify that increased risk establishes causation.

    Held

    The Court held that Calhoun’s training and expertise qualifies her to opine on the specific cause of death in this case. She may not provide an opinion on general causation based on the design of the RnP. She may not opine that increased risk establishes causation.

    Key Takeaway:

    The Court concluded that Calhoun’s general causation opinion, which primarily restates the opinions of other experts, lacked analysis rooted in her own expertise and risked misleading the jury; therefore, it must be excluded. However, her specific causation opinion was deemed admissible, as it relied on a reliable differential diagnosis methodology, which considered and ruled out alternative potential causes of death based on her training and experience. The Court also added that while Calhoun may testify that the RnP’s design increased the risk of harm, she cannot assert that increased risk alone establishes causation for A.B.’s death under Pennsylvania law.

    Please refer to the blog previously published about this case:

    Testimony of the Biomechanical Engineering Expert Witness About the Dangers of Inclined Sleepers Limited

    Case Details:

    Case Caption: Ameena Brown V. Fisher-Price, Inc.
    Docket Number: N20C-01-067
    Court: Superior Court of Delaware, New Castle
    Order Date: December 20, 2024
  • Expert Allegedly Revised His Testimony on the Cause of Deaths in Lucy Letby Trial

    Expert Allegedly Revised His Testimony on the Cause of Deaths in Lucy Letby Trial

    Between 2015 and 2016, Lucy Letby harmed babies in her care with the intention of killing them. The means of harm varied: causing air embolus by introducing air via intravenous lines; forcing air into the abdomen via nasogastric tubes; force feeding milk; poisoning by administering insulin; physical trauma. She alone was present on the unit at the time of all the deaths and deteriorations.

    Following an internal review of the deaths, and the suspension of the applicant from nursing duties, the police began an investigation in May 2017. Letby was convicted in August 2023 of seven counts of murder and seven of attempted murder of infants at the neonatal unit at the Countess of Chester Hospital. She was acquitted on two further counts of attempted murder and the jury was unable to agree on a further six counts of attempted murder. The Court of Appeal rejected Letby’s application for leave to appeal against her convictions after the credibility of Prosecution’s lead expert, Dewi Evans‘ testimony was affirmed.

    Evans, a retired paediatrician, was asked to review initially 33 sets of clinical records involving death or deterioration of an infant on the unit and then a further 28 sets of records.

    He was retained to provide an opinion on the cause of the collapse of each baby. Lucy Letby’s barrister Mark McDonald told a news conference in London that Evans, had allegedly altered his view about how the babies died. Evans added: “Mark McDonald’s observations regarding my evidence is unsubstantiated, unfounded, inaccurate. Evans said the only change in his evidence related to the date a child referred to as Baby C died but insisted it was a simple error by the prosecution.

    Pediatrics Expert Witness

    Dewi Evans provides expert medical advice regarding clinical issues where child abuse is suspected or where there are allegations of clinical negligence. He has prepared reports for the Court for over 25 years and has given evidence in court in Wales, England, Ireland and Northern Ireland.

    He was appointed a consultant paediatrician in 1980; he had been trained in neonatology although, at the time, this was not a specific sub-specialty, hence he was never a consultant neonatologist; he set up a neonatal intensive care service in Swansea; he designed a new neonatal unit in 1990.

    Get the full story on challenges to Dewi Evans’ expert opinions and testimony with an in-depth Challenge Study. 

    Discussion by the Court

    “The defense will argue that Evans is not a reliable expert, and all the convictions are not safe,” McDonald said. He said: “Remarkably, Evans has now changed his mind on the cause of death of three of the babies: Baby C, Baby I and Baby P.

    The Court was told that one of Letby’s victims, Baby C weighed just 800g (1lb 12oz) when he was born in early June 2015, but despite that, medics recorded that he was in a “good condition” and stable.

    He was being kept in the highest priority section of the neonatal unit, but on the night of 13 June, he suddenly stopped breathing.

    The Court heard Letby, who was the designated nurse in a different section but was present when Baby C collapsed, caused the issue at about 23:15 BST by inserting air into his stomach via a nasogastric tube.

    Medics failed to revive him and he was pronounced dead at 05:58 on 14 June

    According to McDonald, Evans had “revised his opinion in relation to Baby C” and had written a new report which he had given to police months ago. But, he added “despite numerous requests” the prosecution had “yet to give this report to the defense”.

    Evans previously told BBC that Baby C was likely to have died due to “a combination of air and milk” pumped via the nasogastric tube into the stomach, which differed from what he had said in Court when he only mentioned air.

    He told the BBC it had led him “to review the events leading up to Infant C’s collapse and death” and thought it “more likely” that it was an injection of air into the bloodstream, although he stressed either would be “inflicted injury”.

    Key Takeaway:

    Mark McDonald accused Dewi Evans of retracting his earlier statements about how the babies died. Evans allegedly revised his opinion regarding Baby C but failed to provide the defense with his updated report.

    However, Evans said he was “surprised how little he changed his mind” while working on the case.

    Please refer to the blog previously published about this case:

    Lucy Letby Objected to the Prosecution’s Lead Expert’s Testimony Regarding the Collapse of Each Baby

  • Pediatrics Expert Witness’ Opinion on Forceps-Assisted Vaginal Delivery Excluded

    Pediatrics Expert Witness’ Opinion on Forceps-Assisted Vaginal Delivery Excluded

    The present case involved a medical malpractice claim filed by Plaintiffs Tyler Grenier and Jenna Grenier, individually, and as the next friend of minor J.A.G., against the Defendant United States of America (“Defendant”). The Plaintiffs alleged medical negligence at Tripler Army Medical Center (“Tripler”) concerning prenatal care and labor provided to Plaintiff Jenna Grenier (“Jenna”) and the delivery of J.A.G. The claims included severe physical injuries sustained by Jenna and J.A.G., negligent infliction of emotional distress on Tyler and Jenna, loss of filial consortium, and Tyler’s loss of spousal consortium.

    In the current motion, the Defendant sought to strike the expert testimony of Ofer Levy, a pediatrics expert witness presented by the Plaintiffs. Defendant argued that Levy’s expert report was filed after the expert report deadline, as a rebuttal report, and that he had not been previously disclosed as an expert.

    The Plaintiffs filed their opposition on August 13, 2024, asserting that Levy’s report was timely because the rebuttal disclosure deadline had been extended to June 10, 2024, the same day his report was disclosed.

    Defendant replied on August 20, 2024, contending that Ofer Levy’s expert report is not a rebuttal report because it did not respond to any new information and it is an entirely new expert witness with new opinions that should have been disclosed by the expert witness disclosure deadline of March 11, 2024. 

    Pediatrics Expert Witness

    Pediatrics Expert Witness

    Ofer Levy is principal investigator, staff physician and the Director of the Precision Vaccines Program at Boston Children’s Hospital, Professor of Pediatrics at Harvard Medical School, and Associate Member of the Broad Institute of MIT and Harvard. 

    After graduating from the Bronx High School of Science and then Yale College (B.S., Molecular Biophysics & Biochemistry), Levy received his MD and PhD degrees from New York University. 

    Want to know more about the challenges Ofer Levy has faced? Get the full details with our Challenge Study report.  

    Discussion by the Court

    Dispute Over the Nature of Ofer Levy’s Report

    The parties agreed that Ofer Levy’s report was filed within the deadline for rebuttal expert reports. However, they disagreed on whether the report qualified as a rebuttal or an initial expert report. The Court determined that the report was an initial expert report, not a proper rebuttal.

    Ofer Levy’s opinion stated that the forceps-assisted vaginal delivery caused the minor Plaintiff’s injuries and that a cesarean section should have been performed instead. He further opined that the perinatal injuries would have been avoided with a cesarean section. This opinion mirrored that of Plaintiffs’ obstetrics and gynecology expert witness, Adam V. Levy, who had similarly concluded that a cesarean delivery would have prevented the injuries.

    The Court found that Ofer Levy’s report went beyond providing a rebuttal. Instead, it sought to reinforce the opinions already expressed by Adam V. Levy. This was impermissible, as it did not respond to new evidence but rather bolstered the original expert report. The Court referenced Parenti v. Cnty. of Monterey, where a purported rebuttal was excluded because it merely reinforced the original expert’s opinions.

    Violation of Federal Rule of Civil Procedure 37(c)(1)

    Under Federal Rule of Civil Procedure 37(c)(1), if a party fails to disclose expert testimony as required, the Court may exclude the testimony unless the failure is substantially justified or harmless. The Court ruled that Ofer Levy’s failure to disclose his expert status and report by the deadline was neither justified nor harmless. Consequently, the Court determined that the appropriate sanction was to strike Levy’s expert testimony and report.

    Factors for Exclusion Sanction

    To decide whether exclusion was appropriate, the Court considered several factors:

    1. The public’s interest in the swift resolution of litigation.
    2. The Court’s need to manage its docket efficiently.
    3. The risk of prejudice to the Defendant.
    4. The public policy favoring the resolution of cases on their merits.
    5. The availability of less severe sanctions.

    The Court found that the first three factors supported exclusion. The untimely disclosure would cause delays, which weighed against the Plaintiffs. The fourth factor was neutral, as striking Levy’s report would not dispose of the case. Finally, the fifth factor supported exclusion because the Plaintiffs could still proceed with their claims and trial without Levy’s testimony. Therefore, the Court decided to strike Levy’s expert report and testimony.

    Held:

    The Court, in light of the aforementioned discussion, granted Defendant’s motion to strike Plaintiff’s pediatrics expert witness Ofer Levy’s expert report and testimony.

    Key Takeaway:

    The Court struck the expert testimony of Ofer Levy because his report, filed after the expert deadline, was deemed an initial expert report rather than a rebuttal. The Court found that Levy’s testimony merely reinforced the opinions of another expert, Adam V. Levy, instead of responding to new evidence. Since Levy’s untimely disclosure was neither substantially justified nor harmless, the Court ruled that his report and testimony should be excluded as a sanction under Federal Rule of Civil Procedure 37(c)(1).

    Please refer to the blogs previously published about this case:

    Case Details:

    Case caption: Grenier Et Al V. United States Of America
    Docket Number: 1:22cv396
    Court: United States District Court for the District of Hawaii
    Dated: November 17, 2024
  • Lucy Letby Objected to the Prosecution’s Lead Expert’s Testimony Regarding the Collapse of Each Baby

    Lucy Letby Objected to the Prosecution’s Lead Expert’s Testimony Regarding the Collapse of Each Baby

    Between 2015 and 2016, Lucy Letby harmed babies in her care with the intention of killing them. The means of harm varied: causing air embolus by introducing air via intravenous lines; forcing air into the abdomen via nasogastric tubes; force feeding milk; poisoning by administering insulin; physical trauma. She alone was present on the unit at the time of all the deaths and deteriorations.

    Following an internal review of the deaths, and the suspension of the applicant from nursing duties, the police began an investigation in May 2017. Letby was convicted in August 2023 of seven counts of murder and seven of attempted murder of infants at the neonatal unit at the Countess of Chester Hospital. She was acquitted on two further counts of attempted murder and the jury was unable to agree on a further six counts of attempted murder. The Court of Appeal rejected Letby’s application for leave to appeal against her convictions after the credibility of Prosecution’s lead expert, Dewi Evans‘ testimony was affirmed.

    Evans, a retired paediatrician, was asked to review initially 33 sets of clinical records involving death or deterioration of an infant on the unit and then a further 28 sets of records.

    He was asked to provide an opinion on the cause of the collapse of each baby. As the lead expert during the investigation, he advised the police to seek further expertise from the fields of histopathology; paediatric radiology; paediatric haematology; paediatric endocrinology; paediatric neuroradiology and paediatric surgery.

    Pediatrics Expert Witness

    Dewi Evans provides expert medical advice regarding clinical issues where child abuse is suspected or where there are allegations of clinical negligence. He has prepared reports for the Court for over 25 years and has given evidence in court in Wales, England, Ireland and Northern Ireland.

    He was appointed a consultant paediatrician in 1980; he had been trained in neonatology although, at the time, this was not a specific sub-specialty, hence he was never a consultant neonatologist; he set up a neonatal intensive care service in Swansea; he designed a new neonatal unit in 1990.

    Get the full story on challenges to Dewi Evans’ expert opinions and testimony with an in-depth Challenge Study. 

    Discussion by the Court

    Dewi Evans

    On appeal, Letby argued that Evans’ evidence should have been excluded from the jury’s consideration because he was not a neonatologist; he had not been in full time practice since 2009; most of his current work was purely as an expert witness; he could not be considered sufficiently independent because he had been part of the original investigation; his evidence was not sufficiently reliable to be admitted; he had been the subject of previous adverse judicial comment.

    The Court, however, found him to be a “highly experienced consultant paediatrician” with “decades of clinical hands-on experience with neonates”. Moreover, to the extent that he was acting as an investigator or director of the investigation, he was not doing so in a way that precluded him from being an expert witness in the case. Evans’ evidence was provided without him being given access to the other circumstantial material, so it was uninfluenced by matters outside his expertise and knowledge. Also, his opinions were independently corroborated by other expert witnesses.

    As for being the subject of previous adverse judicial comment, Evans pointed out that the document in question was not in fact an expert witness report for Court, but a letter to solicitors in a care case. It had been used by them without his knowledge or consent in applying for permission to appeal. The criticism was put to him; he had not been aware of it before; he explained his understanding of the context; the matter was left for the jury to consider. The Court found nothing wrong with that approach.

    Air Embolus in Neonates

    Letby sought to admit fresh evidence in the form of two reports from a neonatologist, Shoo Lee, to address the defense assertion that the prosecution experts were wrong to diagnose air embolus on the basis of a research paper. The Court held that ““although their direct clinical experience of air embolus in neonates was inevitably very limited, each of the prosecution’s expert witnesses was well qualified in their respective fields to give the evidence which they gave.”

    Defense did not call any expert witness evidence at trial

    It was open to the defense to call expert evidence of their own. They did instruct a number of experts and serve their reports on the prosecution, but they did not call any expert witness evidence at trial.

    In the trial, the result was that the prosecution expert witnesses were challenged strongly by the defense; but the points made in the challenge could only become evidence in the case if, either the defense called their own witnesses who could then provide that evidence, or the prosecution witnesses accepted the points made in the challenge.

    Held

    The Court of Appeal admitted Dewi Evans’ testimony and rejected Letby’s application for leave to appeal against her convictions.

    Key Takeaway:

    Evans was familiar with the courts’ approach and ready to deal with the inevitable challenges of the criminal justice system.

    The issue of admissibility (whether or not evidence is put before the jury) is a question of law which is dealt with by the judge. If they rule that the evidence is admissible, it is then considered by the jury. The ruling to admit the evidence can be challenged on appeal.

    The issue of the weight to give to any evidence is a matter entirely for the jury. Counsel can seek to persuade them to take one view or another of the evidence. The judge must leave it up to the jury. What weight the jury has in fact given to each piece of evidence might be inferred from the verdict that they reach.

    Case Details:

    Case Caption: Letby V. R
    Case Number: 202303209B4
    Court: Court of Appeal, Criminal Division
    Order Date: July 2, 2024
  • Pediatrics Expert Witness’ Psychological Diagnoses of the Three Children Admitted

    Pediatrics Expert Witness’ Psychological Diagnoses of the Three Children Admitted

    Respondent traveled with her three minor children, J.H., A.H., and S.H., from Mexico to the United States in 2022. Petitioner sought the return of his minor children to Mexico under the Hague Convention. Respondent called Dr. Minal Giri to testify as an expert witness on July 16 and Dr. Paul Gillingham to testify as an expert witness on August 5. Petitioner reserved his objections during the hearing and now moves to exclude the opinions and testimony of Giri and Gillingham.

    Pediatrics Expert Witness 

    Minal Giri is a licensed pediatrician with a medical degree from the University of Chicago. She has been a practicing pediatrician for over twenty years, since she completed her residency at Lutheran General Hospital in 2002. As part of her training, she studied mental health and mental trauma experienced by children. And as part of her current practice, she sees and treats children suffering from mental health conditions such as anxiety and depression on a regular basis. She completed a Global Mental Health Certificate at Harvard University in 2020 that focused on refugee trauma and recovery. 

    Get the full story on challenges to Minal Giri’s expert opinions and testimony with an in-depth Challenge Study. 

    History Expert Witness 

    Paul Gillingham is a Professor in the History and Spanish & Portuguese Departments of Northwestern University and holds a Ph.D in the history of modern Mexico.

    Get the full story on challenges to Paul Gillingham’s expert opinions and testimony with an in-depth Challenge Study.

    Discussion by the Court

    Minal Giri

    In her report and testimony, Giri diagnosed J.H. with post-traumatic stress disorder (“PTSD”) and generalized anxiety disorder, A.H. with PTSD and generalized anxiety disorder, and S.H. with separation anxiety disorder. She opined that if the three children were to return to Mexico, this would compound their existing trauma and exacerbate their disorders. 

    Qualifications

    First, Petitioner argued that Giri is not qualified to provide psychological diagnoses because she is neither a psychiatrist nor a psychologist. But Giri has specific experience diagnosing and treating mental health and mental trauma for immigrant and refugee children. She has written expert reports for approximately 35 prior cases, each of which involved the mental evaluation of children or adults seeking asylum and immigration relief. The Court held that Giri is qualified to provide psychological diagnoses for the three children.

    Methodology

    Petitioner challenged Giri’s methodology. Primarily, Petitioner argued that Giri’s methodology was flawed because she did not ask questions during the interviews about possible causes of the children’s symptoms, beyond their father’s alleged mistreatment. Moreover, Petitioner contended that Giri’s reliance on the Istanbul Protocol implies a false assumption by Giri that the children had been traumatized. 

    The Court held that Giri’s methodology was sound. She interviewed J.H., A.H., and S.H. consistent with her training as a pediatrician and reached conclusions based on those interviews.

    Petitioner also argued that Giri’s methodology was flawed because the DSM-5 contains eight requirements for a PTSD diagnosis and Giri’s reports for J.H. and A.H. enumerated just five of these requirements. The Court held that Petitioner’s cross-examination was the appropriate remedy to attack the missing information rather than exclusion of Giri’s entire report.

    Petitioner argued that Giri’s methodology was flawed because Giri was not present when J.H. and A.H. filled out the GAD-7 and PHQ-9 questionnaires (screening tests for mental health conditions) and thus had no way to verify their answers. Giri testified that her diagnoses were based on the interviews, not the questionnaires, and that the questionnaires merely confirmed the diagnoses she had already reached based on the interviews. The Court affirmed the admissibility of the diagnoses.

    Paul Gillingham

    In his report and during his testimony, Gillingham offered an opinion on 1) the general level of violence in Respondent’s hometown of Zitácuaro; 2) whether, based on his understanding of Mexico and Zitácuaro, Respondent’s allegations of violence were credible; and 3) whether, based on his understanding of Mexico and Zitácuaro, Respondent would have been able to rely on the police or court system for recourse in her divorce case or for physical protection.

    First, Petitioner argued that Gillingham’s report should be excluded because Gillingham failed to disclose all his sources. The Court held that this particular nondisclosure does not warrant exclusion of the entire report. Gillingham testified that he had relied on three data points in forming his opinion about violence in Zitácuaro: homicide rates, internally displaced persons, and disappearances. Gillingham’s report disclosed homicide rates but failed to disclose anything about internally displaced persons or disappearances. Overall, Gillingham’s eighteen-page report contains thorough citations with fifty-eight footnotes. Moreover, Petitioner’s counsel effectively and extensively cross-examined Gillingham on this issue. The Court found that Petitioner fully cured any prejudice stemming from the non-disclosure and thus that the non-disclosure was harmless.

    Second, Petitioner argued that Gillingham’s report and testimony should be excluded as unreliable and irrelevant because Gillingham failed to rely on facts specific to this case. However, Gillingham’s mission was to take the allegations made by Respondent and to assess their general plausibility given what he knows, as an expert, about the political and criminal situation in Zitácuaro. The Court held that the nature of Gillingham’s testimony is unusual. It is less of an analysis and more a sharing of information about Zitácuaro. But there is nothing to suggest that the information provided by Gillingham is flawed. The Court found it at least minimally relevant and thus admissible.

    Held

    The Court denied the Petitioner’s motions to exclude the opinions and testimony of Minal Giri and Paul Gillingham.

    Key Takeaway:

    • All expert opinions come with assumptions and conclusions. Petitioner is free to disagree with Giri’s assumptions and conclusions, but that does not render Giri’s testimony inadmissible.
    • There is nothing to suggest that the information provided by Gillingham is flawed. And his testimony is at least minimally relevant to provide the Court with context for Respondent’s hometown of Zitácuaro. Whether the Court will ultimately afford Gillingham’s testimony much weight in deciding this case is an open question. The testimony, however, is at least minimally relevant and thus admissible.

    Case Details:

    Case Caption: Delgado Moreno V. Hernandez Escamilla
    Docket Number: 1:23cv15736
    Court: United States District Court for the Northern District of Illinois, Eastern Division
    Order Date: August 27, 2024
  • Pediatrics Expert Witness Testimony Limited Despite Thorough Medical Literature Review

    Pediatrics Expert Witness Testimony Limited Despite Thorough Medical Literature Review

    Gerber Products Company sells several infant formula products. This case concerns Gerber Good Start Gentle (sometimes referred to below as “GSG”). Unlike most other infant formulas, which are made with “intact” cow’s milk protein, GSG uses cow’s milk protein that has been partially broken down (the technical term is “100% Whey-Protein Partially Hydrolyzed”).

    Good Start Gentle was the first formula that the U.S. Food and Drug Administration permitted to make a “qualified health claim” — that is, a limited health claim. Specifically, in response to a petition from Gerber, the FDA advised that it would exercise its enforcement discretion not to challenge certain specified, modest claims about GSG. The claims related to atopic dermatitis, otherwise known as eczema. Atopic dermatitis is the most common allergic disease in infants.

    The relief the FDA accorded Gerber was indeed very limited in scope. Gerber responded to the FDA’s permitting this qualified health claim by launching new advertising for GSG: it implemented packaging that stated, among other things, that GSG was the first and “only” formula “to reduce” an infant’s “risk of developing allergies.”

    Plaintiffs asserted that Gerber falsely advertised that GSG (a) could reduce the risk of developing allergies and (b) had earned the FDA’s endorsement.

    The Plaintiffs moved to exclude the testimony of Gerber’s proposed expert witness, Jose M. Saavedra.

    Pediatrics Expert Witness

    Jose M. Saavedra is Associate Professor of Pediatrics, at the Johns Hopkins University School of Medicine. He is a pediatrician, gastroenterologist, investigator, educator, and medical and scientific business executive. Saavedra carried out seminal and groundbreaking work in the area of probiotics in pediatrics, and has an extensive record of publications in nutrition, and in the area of intestinal microbiota, immunity, and preventive nutritional strategies. In the latter part of his career, he also worked as Medical Director for Nestlé Nutrition in North America, and until recently as Global Chief Medical Officer for Nestlé Nutrition, in Vevey, Switzerland. Saavedra is Chairman of the Board of the Nestlé Nutrition Institute. During that time, he expanded scientific innovation, and enhanced Nestlé’s educational and research activities focused on infant and childhood health.

    He spearheaded a number of collaborative initiatives, many on education and dissemination of nutrition knowledge, focused on Early Childhood Nutrition Education, with pediatric and nutrition societies and organizations globally, including NASPGHAN, ESPGHAN, the American Academy of Pediatrics, the National Academies of Science in Washington DC., and UNESCO. He recently published a book entirely dedicated to the impact of early life nutrition on life-long health consequences, focusing on nutrition in the first 1,000 days.

    Discussion by the Court

    According to his report, Saavedra was expected to opine that “Gerber had, and has, a scientifically sound basis” to represent that “feeding [GSG] instead of intact cow milk protein formula (CMF) to infants with a family history of allergy in the first month of life can reduce the risk that said infants will develop allergies, particularly and specifically atopic dermatitis.” He was also expected to opine that “there was a significant and substantial body of scientific evidence to support the representations in the Challenged Advertisements.” These opinions, of course, were more forceful than the claims the FDA permitted Gerber to make on the same subject.

    The Plaintiffs articulated multiple bases for excluding Saavedra’s opinion: alleging bias, stating that his opinions relied on inadequate data from studies that had been criticized for their methodology and data reporting, and asserting that his testimony would be both prejudicial and confusing.

    Alleged Bias

    The Plaintiffs argued that Saavedra should be disqualified because he has worked for Nestlé, Gerber’s parent company, for two decades, during which he endeavored to prove that “100% Whey-Protein Partially Hydrolyzed” formula reduces allergy risk.

    The Court held that an expert witness’s employment with a party, however, “does not automatically disqualify him from rendering expert testimony in a case” involving that party. Gerber may seek to impeach Saavedra with his relationship with Gerber, but it did not warrant excluding his opinion.

    Adequacy of Data, Methodology and Studies

    The Plaintiffs argued that Saavedra did not conduct any of the research himself, and hence his expert opinions warranted exclusion.

    Saavedra’s report is at base a literature review. He considered “twenty peer-reviewed publications of prospective, controlled clinical trials in 12 distinct healthy infant cohorts” — studies that assessed “the reduction in the incidence of allergy” when GSG or another partially hydrolyzed formula is used instead of traditional cow’s milk protein formula.

    Saavedra called four of these studies “high quality,” in light of the “size of the study population, the rigor of randomization, rigor of feeding intervention, adequacy of definition of outcomes, diagnostic criteria and clinical diagnosis, follow up, and data integrity.” Three of these “high quality” studies expressly compared outcomes between infants fed GSG (or the equivalent) versus cow’s milk protein formulas without confounding variables. Those three studies all reported that the subjects receiving GSG or its equivalent saw statistically significant reductions in atopic dermatitis or other allergic diseases for at least a short time. Other studies that Saavedra reviewed showed no reduction in allergies from feeding GSG analogs instead of cow’s milk formula, or at least no statistically significant reduction.

    Review of Medical Literature

    A review of medical literature is a reliable methodology for Daubert purposes. It is axiomatic that experts can rely on hearsay. 

    The Plaintiffs’ motion compelled the Court to determine whether Saavedra had “extrapolated his conclusions from the medical literature in a scientifically reliable fashion.”

    Saavedra included findings published after Gerber disseminated the challenged advertisements in his literature review. For example, Saavedra justified his opinions in part because, since the challenged ads appeared, a study had reported that allergy-risk-reduction benefits from GSG could persist into adolescence. Moreover, he relied on a 2018 “meta-analysis” of data published through 2017 that “reported a 39% incidence reduction in all allergies with exclusive feeding of” GSG or the equivalent.

    These studies were too recent to be relevant. Here, the operative question was whether Gerber’s challenged ads were misleading when made, not whether they would be misleading if made today.

    The challenged ads all impliedly represented that Gerber believed them, and by extension, that Gerber “knew facts which justified” that belief.

    Where only part of an expert’s testimony meets the Rule 702 standard of admissibility, the Court should limit the expert’s testimony, rather than “throw the good out with the bad.”

    Beyond the temporal issue, the Plaintiffs leveled numerous criticisms of the studies on which Saavedra relied most heavily. The Plaintiffs argued that Saavedra’s studies were not “high quality” because multiple groups contended they had significant methodological and reporting issues.

    The Court held that these criticisms did not demonstrate that Saavedra’s proffered opinions extrapolated from “studies that were simply inadequate to support the conclusions reached.” 

    Dual Testimony

    Plaintiffs argued that the Court should not permit Saavedra to testify both as an expert and as a fact witness. The Court may exclude such dual testimony if the danger of unfair prejudice substantially outweighs its probative value.

    The Plaintiffs argued that Saavedra’s dual testimony was objectionable because Saavedra, in his deposition conceded  that he would not differentiate between fact and expert testimony at trial. Even assuming such a concession could change the Rule 403 calculus, Saavedra did not make it. When  Saavedra said he would not “differentiate” between his two capacities, he was discussing his right to compensation, not how he would testify. In any event, the Court is free to revisit this question as trial approaches.

    Held

    Plaintiffs’ motion to exclude the expert testimony of Jose Saavedra was denied in substantial part. The Court ordered Gerber to submit a revised expert report from Saavedra that limited his methodology to publications available at the time Plaintiff made particular claims in GSG advertising. 

    Key Takeaways:

    1. Bias Considerations: Employment history or affiliations with a party involved in the case do not automatically disqualify an expert from providing testimony. The opposing party may attempt to impeach the expert’s credibility based on such relationships, but it doesn’t necessarily warrant exclusion of their opinion.
    2. Adequacy of Data and Methodology: Experts may rely on literature reviews to form their opinions. The Court may scrutinize the quality of studies cited by the expert, but if the expert adequately demonstrates the reliability of their methodology and the relevance of the data, their testimony may be admissible.
    3. Review of Medical Literature: The Court may consider a review of medical literature a reliable methodology for expert testimony, provided it meets certain standards of reliability and relevance.
    4. Dual Testimony: Courts may scrutinize the admissibility of dual testimony, where an expert acts both as an expert and a fact witness. The Court should weigh the potential for unfair prejudice against the probative value of such testimony. Additionally, experts should be clear about their roles and capacities in providing testimony to avoid confusion or potential objections.

    Case Details:

    Case Caption: Hasemann Et Al V. Gerber Products Co.
    Docket Number: 1:15cv2995
    Court: United States District Court, New York Eastern
    Order Date: March 25, 2024