| Author | Affiliation |
|---|---|
| Christopher S Greeley, MD | University of Texas Health Science Center at Houston |
The Western Journal of Emergency Medicine has received a detailed critique by Dr Christopher Greeley of the article, “Challenging the Pathophysiologic Connection between Subdural Hematoma, Retinal Hemorrhage, and Shaken Baby Syndrome” by Dr Steven Gabaeff, published in May 2011, Volume XII, Issue 2. The author’s response is even more detailed. The Journalrecognizes that these 2 authorities are diametrically opposed in their opinions, and in the interest of fair academic discourse, we are publishing both the letter to the editor and response to the editor in electronic form for those interested in this highly contentious debate.
We leave it to the reader to judge the original article, its critique, and rebuttal, on their own merits.
The Editor
Challenging the Pathophysiologic Connection between Subdural Hematoma, Retinal Hemorrhage, and Shaken Baby Syndrome
To the Editor
As having board certification in both general pediatrics and child abuse pediatrics, and having experience and training in clinical research and medical literature appraisal, I read with great interest the “Special Contribution” by Dr Steven Gabaeff.1 I appreciate the special relationship that the author has with the Western Journal of Emergency Medicine as having been instrumental in the rebranding from The California Journal of Emergency Medicine, past president of the California chapter of the American Academy of Emergency Medicine, and a current editorial board member. Given the complex and contentious nature of the subject matter, I am impressed that it took less than 4 weeks for a meaningful peer review to occur, for recommending revisions for the author, and for receiving those revisions.
I recognize that there are a number of medical professionals who disagree with some of the accepted clinical features of abusive head trauma (AHT) (formerly referred to as “shaken baby syndrome”) and I believe that critical scrutiny and lively debate of much of clinical medicine is a healthy and necessary endeavor. As a result, there exists a small cadre of professionals who have become denialists to many of the central tenets of AHT2 and use various rhetorical techniques3,4 to further an ideology, and not to meaningfully contribute to the field. Unfortunately, I fear the piece by Dr Gabaeff does not contribute to a substantive deconstruction of some of the basic tenets of child abuse pediatrics or further the discussion. I would like to point out some of the methodologic flaws the author makes so as to afford your readership a more accurate appreciation of this complex and often contentious field. Owing to space constraints, I cannot present a counterfactual argument for each of the presented hypotheses. I will limit my comments to highlighting certain rhetorical sleights that may mislead the reader, and provide some examples from Dr Gabaeff’s text.
Throughout the article, the author uses a common technique of preceding and/or following controversial and unsupported statements with cited comments or phrases. This technique gives the appearance of cited literature support for an unsupported opinion. The first example of this is when the author discusses the work of Dr Ommaya in whiplash forces on the brain and cervical spine of monkeys. The author writes, “With current technology, these neck findings following whiplash injury would be evident as soft tissue swelling from hematoma or edema on magnetic resonance image (MRI) and computed tomography (CT) of the neck.” This is placed before and after well-cited work by Dr Ommaya but is itself uncited, and in the pediatric population has been shown to be untrue.5,6 It is this sentence that is meaningful to clinicians, but it is this sentence that is unsupported. This “citation sandwich” is a common way in which unsupported opinions are given the veil of legitimacy by their proximity to cited and supported concepts. Another example of this is when the author describes the hypothesis that shaking an infant is dangerous. The author writes, “based on analysis of the force required to cause intracranial injury and the impact of shaking on the neck, without some findings of neck injury on imaging, intracranial pathology resulting from human shaking of a previously healthy child should be seriously called into question.” While this statement is uncited, it is preceded by a cited discussion of the G forces required to cause injury and followed by a cited discussion of helmet forces, which occur during football collisions. Of note, the discussion of the forces generated in football collisions is an example of “irrelevant conclusion” (ignoratio elenchi). This technique is used to divert attention away from an underlying argument by introducing a tangential and irrelevant argument theme. The forces generated by the collisions of adults playing football are physiologically and biomechanically unrelated to the theory that shaking of an infant can result in retinal hemorrhages.
Another methodologic flaw the author uses is “denying the antecedent.” This is a technique in which conclusions are made that are not supported by the presented evidence. The author writes, “On this basis, the consideration of intentional impact must be carefully evaluated to diagnose abuse, as it is clear that short falls in household situations are sufficient to cause not only ICT, but even death.” The citation for this is a review of 75,000 falls involving playground equipment reported to the US Consumer Protection Agency, of which 18 were fatal.7 In reading the “Methods” section of this citation, it is readily apparent that none of these were household falls and none involved children younger than 12 months. While this is an important article as support for consideration of falls as a cause of death in young children, to imply that it supports that a short household fall can kill an infant is misleading. Another example of denying the antecedent is when the author discusses the differential diagnosis of retinal hemorrhaging in infants. The author writes, “Lantz found from autopsy work on 425 eyes of the recently deceased that 17% exhibited RHs associated with a variety of diseases and conditions.” The citation for this is a single case report of a 14-month old child who had a crush injury to his head. His evaluation revealed “bilateral dot and blot intraretinal haemorrhages, preretinal haemorrhages, and perimacular retinal folds.” This is another important article but in no way supports the contention offered by the author. (Apparently, the author was intending to refer to Dr Lantz’s 2006 American Academy of Forensic Sciences presentation8 in which he described his experience with 111 people (16% of his total sample) with retinal hemorrhages, only 30 of whom were children. Of these 30, only 19 were younger than 1 year. Dr Lantz reported that 15 of these infants had retinal hemorrhages, which were from nonabusive causes.9 These data have not been published in peer-reviewed literature.
Another example of denying the antecedent in this piece is when the author discusses apparent life-threatening events (ALTE). The author hypothesizes that the symptoms associated with an ALTE (“seizures, decreased muscle tone [limpness], vomiting, failure to thrive, hydrocephalus, altered level of consciousness [LOC], color changes from hypoxic episodes, conventional or dysphagic choking, abnormal breathing patterns, and apnea”) could be the manifestations of a chronic subdural hematoma. Ironically, to support this contention, the author cites a 1968 cohort (pre–computed tomography [CT] technology) of 116 infants with “subdural effusions or hematomas” described by Till.10 Of these 116 infants, nearly half had retinal hemorrhages, a number that “would have been undoubtedly higher if more time had been spent examining the fundi of these babies.”10 Till reports for the subdural collections “no satisfactory explanation in many cases, although trauma is an important factor in the majority.”10 It appears that the citation used to support Dr Gabaeff’s contention that the ALTE-like symptoms of a chronic subdural hematoma (SDH) can be spontaneous is that of a cohort of children many of whom likely had been abused.
Another subtle rhetorical technique used is the “straw man” argument. This is the most widely known rhetorical technique and involves constructing an opposing point of view in a manner that makes it seem unbelievable, and thus easily discountable. The author performs this when he refers to the large number of accidental falls that occur each day, and that “it is illogical to reflexively assume a different, sinister act has occurred in patients who are found to have SDH after an accidental fall. Rather, we should recognize that a very small subset of all accidental falls can and do result in serious brain injury. With a large denominator of accidental falls, the serious brain injuries can and do result from innocent, accidental mechanisms, and each of these cases most likely prompts a medical encounter.” This description makes the “pediatric child abuse specialist” seem irrational and thus unbelievable. In using this rhetorical sleight, one does not have to discuss the data that fatal falls from any height in children are exceedingly rare (55 per year in children younger than 5 years11) nor outline the detailed protocols that hospitals and professional organizations12,13 have regarding the meticulous evaluation of suspect abuse. The straw man argument technique is intended to simply make the opposite position seem unfounded.
Lastly, the author also uses “converse fallacy of hasty generalization.” This is a technique in which a very specific premise is constructed and the conclusions are (mis)applied by generalization. This is a very common technique of rhetorical argument in which a single case report or instance is used to dispel an entire theory. The author uses this technique when he discusses the article by Rooks et al.14This is a study of neuroimaging of newborn infants. Of the 101 infants undergoing neuroimaging, 1 (1%) had “a new frontal SDH on the 2-week MR imaging follow-up examination.” Rooks et al note that this neonate “had bilateral occipital and posterior fossa SDH on initial imaging at birth, confirmed on the 7-day follow-up MR imaging. He was also noted to have extra-axial collections of infancy. At 26-days postnatal age, the MR imaging demonstrated left frontal subdural collections that did not conform to CSF signal intensity.” This single case, that may have had something unique about it, is used to support a recommendation for a screening magnetic resonance imaging on all infants with “subtle behavioral abnormalities to prevent later accusations of abuse if complications arise.” (Of note, this infant was not described by Rooks et al as having hydrocephalus as Dr Gabaeff contends.)
A subtle variant of the converse fallacy of hasty generalization is to simply not provide literature support for a broad generalization. An example of this is when the author discusses the presence of retinal hemorrhages. He writes, “The American Academy of Ophthalmology has endorsed and taught the current corps of ophthalmologists that RH, schisis, retinal folds and vitreous hemorrhage are identified with intentional abuse when in fact these findings are more likely the consequence of metabolic catastrophe within the eye itself and unrelated to shaking forces as discussed above.” This sentence is uncited and nowhere in the article does the author refer to data on metabolic diseases and retinal findings. While case reports are quite rare of infants or children with Menke disease, von Willebrand disease, leukemia, and glutaria aciduria (to name a few) who have been noted to have retinal hemorrhages, the author’s sweeping generalization is simply unsupported by clinical practice or medical literature.
In closely appraising the “Special Contribution” by Dr Gabaeff, we see a number of concerning logical fallacies and rhetorical sleights of hand. While this piece is not a systematic review and simply represents the opinion of the author, much of what is written is intended to be used in legal proceedings, and to be cited as being from a peer-reviewed publication. The distinction between a methodologically rigorous systematic review and an opinion piece will be lost on many readers (and juries). The peer-review process is seen by many uninitiated readers as “validating as true.” As a sophisticated end-user of the medical literature, I am continually reminded it is ultimately up to me to critically scrutinize everything that I read and to assess the quality of methodology and data presented. Given the adversarial nature of some of the scholarship of AHT, I am very conscientious of many of the logical and rhetorical landmines readers can encounter. While it is I who ultimately assigns meaning and value to what I read, it is beholden to journals to maintain very high standard of quality and to not create artificial confusion where none exists. I fear the piece by Dr Gabaeff contributes little to the discussion and merely obfuscates the truth.
Footnotes
Conflicts of Interest: By the WestJEM article submission agreement, all authors are required to disclose all affiliations, funding, sources, and financial or management relationships that could be perceived as potential sources of bias. The author disclosed none.
Reprints available through open access at http://escholarship.org/uc/uciem_westjem
DOI: 10.5811/westjem.
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