retinopathy of prematurity.org
Baby-harming medical research
about baby-blinding retinopathy of prematurity
by H. Peter Aleff, 2005 to 2009
3.7. Some early flawed studies of ROP and light
Many neonatologists say that the nursery lights do not harm preemies because they were taught in medical school that an often cited trial published in 1952 had ruled out any connection between exposure to light and ROP. Its authors had patched one eye of each of 22 preemies with gauze, and both eyes of another 33 infants born below 2000 gram whom they then compared with a not further described
Then they reported that just as many of the patched eyes had developed ROP as among the unpatched ones which had been exposed not only to the ambient light but also to ophthalmoscopic examinations and to the mydriatic drops used to widen the pupils for them, and that therefore none of these three agents could be causing ROP.
However, one of the two co-authors was Reese, and an inspection of their study shows indeed his signature shoddy thinking. He and his co-author Locke had designed and performed that study so poorly that it appears more as an attempt to officially dispose in one hasty catch-all study of three other potential causes for ROP that could imperil the planned condemnation of oxygen.
The authors said that light “has been mentioned in almost every discussion of the etiology” of ROP ever since Terry had suggested its role, but they did not even bother to mention the type or intensity of the light in their nursery. They also asserted carelessly that their gauze eye patches “shut out all light” and “prevent any penetration of light” whereas actual measurements of such gauze patches have shown that “gauze pads [have] about 20% transmittance, well applied”.
Most importantly, both those highly educated medical doctors must have been aware of the even then common knowledge that damage from bright light, such as from staring at the sun, accumulates in adult eyes in a matter of minutes or even seconds to dangerous levels. They should also have known that the eyes of preemies are much more vulnerable to any such injury than those of adults, or else they had no business pretending to be doctors.
Yet, Locke and Reese patched none of the allegedly protected eyes earlier than four hours after birth, and some of them as late as “within 24 hours”. That is more than enough time for the fluorescent light to grossly overdose the fragile retinae of any preemie with damaging blue and violet radiation, and to fully explain the lack of an outcome difference between the unprotected and the only allegedly protected eyes.
Still, that slipshod study by Locke and Reese did its intended job of paving the way for the oxygen myth that would disguise the planned euthanasia program and end the epidemic of baby-blinding by killing its potential victims. And the fact that this small-scale and so fatally flawed study kept getting cited as the main argument against the well documented hazards from fluorescent nursery lamps highlights the dangerously uncritical acceptance of medical studies among those nursery doctors who believe this misleading argument.
By the mid and late 1960s, researchers studying the safety of laser light for industrial applications began to document formally that light can damage eyes not just by burning the retina with heat, as in welding accidents or sun-staring, but also through a slightly slower, non-thermal process which they found to be photochemical,,.
This growing body of knowledge, together with the then recent but already widespread use of intense light to treat bilirubin jaundice in newborn babies, led some physicians to re-open the question about the effect of bright light on the eyes of the preemies exposed to it.
In August 1970, a team of physicians from Boston and Philadelphia described in their paper "Retinal Changes produced by Phototherapy" how they had placed newborn piglets under phototherapy lamps with a total irradiance of 300 ftc
They said they had picked piglets because
One of the piglets lost the patch over its control eye which had not been dilated. That eye remained relatively protected by its heavy and hair-covered eyelids and thick eyelashes, and it had been exposed to the lights for less than twelve hours.
However, already the next day that piglet had become totally blind, in both its dilated as well as its undlilated eye. When its retinae were examined three weeks later under an electron microscope, both showed virtually the same "marked damage" as all the other piglets' more fully exposed retinae. The researchers concluded that preemie eyes exposed to phototherapy lights should be shielded with the utmost care, and they warned:
Despite this alarming confirmation of the hazards from light, and although one of the study authors became soon thereafter a member of the American Academy of Pediatrics’ Committee on Fetus and Newborn, that Committee did not change its recommendations for nursery lighting which specified at that time 100 ftc of fluorescent light, or about a third of the intensity that had so quickly destroyed all the eyes of all the piglets, even the partially protected one.
Please note that the eyelids and irises of preemies are virtually transparent and a closer match to the dilated piglet eyes than to the one partly protected eye that had significantly reduced the intensity of the exposure but still incurred the same damage.
Anyone concerned with the safety of preemies would have immediately protected all of them from any irradiation above a very small fraction of these so obviously retina-damaging intensities, particularly during the by then revived ROP epidemic of retinal damage. However, the learned doctors on that Committee charged with the safety of America's babies did nothing to alert anyone about the danger one of them had just so clearly documented. This is "medical ethics" in action.
The pediatric dogma derived from the bogus oxygen study was so firmly established that nursery doctors had little to gain from questioning the Academy-specified nursery lighting. No further evaluation of short-term effects from nursery lighting was published for another 15 years.
Meanwhile, a few other studies searched for long-term effects and could not find any, but they looked among the wrong patients and were also in other respects grossly flawed and misleading. In all these follow-up studies, only those ex-preemies were included who successfully completed a series of eye tests,,.
The authors of one paper even stated that in selecting patients for their study they had specifically excluded children with ROP or other eye problems, and that they had picked only those with no history of visual or other neurologic dysfunction. Then they deduced from their so doctored sample that none of the examined eyes showed any observable damage from nursery lights and that therefore these lights were safe.
A logical equivalent would be to
only white marbles from a basket containing marbles of various
colors, and then to deduce from that selective sampling that all the
marbles in the basket must be white. All these studies were
ill conceived and useless, and yet they have frequently been cited
by many nursery doctors as support for the assertion that standard
nursery lighting is safe for immature eyes.
In late 1982, at long last, the child psychologist Dr. Penny Glass reopened the question that her medical colleagues considered settled. She and her co-authors covered the top and back of each isolette in two Washington, D.C., nurseries with permanently mounted gray filters. Then they reported that so reducing the light on the baby from 60 ftc to 25 ftc had reduced the number of ROP victims in both their nurseries. In their highest-risk group, the preemies with birth weights below 1000 grams, the ROP rate had decreased from 86% before the filters to 54% after this partial light reduction.
The results of Glass’ team were the most dramatic reduction in both incidence and severity that any of the non-rigged approaches to ROP had ever shown. For the above highest-risk group of babies, there was only one chance in a hundred that the reduction in eye damage might be a random coincidence and had nothing to do with the light reduction. For all the babies in all the groups together, that chance was given as almost one in twenty. The authors concluded that
However, for some of the heavier subgroups the mathematical correlation fell slightly short of that magical 95% probability which doctors are taught to view as the so-called statistical significance level to be met when evaluating the efficacy of a treatment.
This mindless test for "statistical significance" was invented around 1920 by the British mathematician Ronald Fisher who arbitrarily picked a probability for a chance result of five per cent because it made his manual calculations easier. Many users of this "significance" concept have thoughtlessly confused it with "importance", particularly in medical writings, and various critics have denounced this obvious error. For instance, Stephen T. Ziliak and Deirdre N. McCloskey wrote in their 2007 book "The Cult of Statistical Significance: How the Standard Error Costs Us Jobs, Justice, and Lives" as the summary of their second chapter
"Crossing frantically a busy street to save your child from certain death is a good gamble. Crossing frantically to get another mustard packet for your hot dog is not. The size of the potential loss if you don't hurry to save your child is larger, most will agree, than the potential loss if you don't get the mustard. But a majority of scientists in economics, medicine, and other statistical fields appear not to grasp the difference. If they have been trained in exclusively Fisherian methods (and nearly all of them have) they look only for a probability of success in the crossing—the existence of a probability of success better than .99 or .95 or .90, and this within the restricted frame of sampling—ignoring in any spiritual or financial currency the value of the prize and the expected cost of pursuing it. In the life and human sciences a majority of scientists look at the world with what we have dubbed "the sizeless stare of statistical significance." [15A].
Moreover, and very unfortunately, the study authors had called the shading a treatment instead of what it really was: a reduction in dosage of the almost bilirubin-strength irradiation treatment they had been administering indiscriminately to all babies all along under the standard fluorescent ceiling lights.
Calling the shielding from light a “treatment” instead of a withdrawal of that treatment may have resulted from the same confusion that makes doctors call their work “health care” when in fact they provide mostly care for the sick. This confusion has old roots because already the ancient Greeks said of their healing god Asklepius that he held in each hand a vial, one with a cure and one full of poison, and that he often confused the two.
In modern America, this medical confusion between a treatment and its reduction triggered the conditioned medical reflex for efficacy evaluation that prevented both the Glass team and their critics from realizing that the safety of the indiscriminate treatment with light, not the efficacy of its partial withdrawal, was the real issue.
In safety assessments, one does not wait for harmful effects to reach an arbitrary level of "statistical significance" to recognize them as a problem. Safety professionals take even a weak association with harm as a danger signal.
And no sane parents would willingly expose their baby to those lamps if they knew there were almost 19 chances out of 20 that this light could damage her or his eyes. But their baby’s doctors don’t inform them about that danger because from their inverted medithink perspective they don’t see that risk as significant.
Advocates of bright nursery lights dismissed the Glass et al. study also because the groups of preemies exposed to 60 ftc and 25 ftc had not been studied simultaneously, but serially. Many of them said that such sequential study designs are not valid,,,.
Ironically, the 1953 bogus study which is the basis for the mainstream neonatologist belief about oxygen as the alleged cause of ROP had a very similar sequential design. There, infants were assigned to the "routine oxygen" group only during the first three months of the investigation. Then the study team decided that the oxygen to be tested was just too risky to expose any babies to it. They completely ditched the pretense of running a "double-blind controlled" trial by doing away with the controls and with their impartial ignorance of the babies' group assignments.
Then they compared the results from this very small "routine oxygen" group with those from the much larger "curtailed oxygen" group, most of whose members were enrolled during the remaining nine months of the study. The study description stated:
According to the logic of those who dismiss the Glass et al. study of light reduction, a sequential study design is "not scientifically credible" and is "weakened by methodological shortcomings" when its results support the light-damage theory.
However, the same sequential study design is acceptable to these critics when it supports the bogus oxygen theory,, or when it denies the role of light, as in the case of the 33 babies with two patched eyes in the slipshod Locke and Reese study above.
3.9. Delayed shading did not reduce ROP
Three months after Glass et al. had published their results, and despite these objections against before-and-after comparison studies in the pediatric community, three nurses in the Newborn Special Care Unit of the Yale/New Haven Hospital prepared to check the results of the Glass team with their own before-and-after comparison study.
They laid receiving blankets over the top half of the isolettes and then measured the light levels at the face of each baby. However, the top is not where the preemies’ eyes are directed; they all lie with their head on its side, their upper field of view filled with rows of ceiling lamps.
Moreover, these nurses repeated the same blatant timing error from Locke and Reese’s 1952 slipshod study of eye-patching. They covered the isolettes only after the babies' "first few days", although they acknowledged that "the most crucial time for reduction of light intensity for the sick premature infant who requires oxygen and ventilatory support may be immediately after birth".
After two years of so providing too little protection too late, these nurses compared the incidence of ROP in their nursery with the incidence during the preceding two years when they had not tried to shield the babies and had not measured the light intensity. They found no significant difference in the incidences of ROP and concluded, despite the blatant contradiction in their discussion of the timing, that decreasing the light exposure in their study had not prevented any blinding.
The logic behind this type of clinical research is the equivalent of applying sunscreen only after baking in the sun and then concluding, as the so treated skin blisters anyway, that sunscreen does not prevent sunburn.
This patently illogical study was again widely cited as having exonerated the light from any role in ROP. Even more misleadingly, one of the authors co-wrote elsewhere a defense of the bright lighting as if their study had settled the question forever:
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