Standard of care, expert witnesses, and malpractice lawsuits.

AJR 2011; 196:W489 0361–803X/11/1964–W489 © American Roentgen Ray Society Standard of Care, Expert Witnesses, and Malpractice Lawsuits The suggestion of Dr. Semelka and his coauthors [1] that the standard of care in medical malpractice lawsuits involving allegations of missed radiologic findings be determined by blind readings of external radiologists warrants further comment. In the case described by the authors, four expert witnesses for the plaintiff reported that CT disclosed fractures of T3 and T10 as well as a 1-mm widening of the T10 facet joints. None of 31 radiologists who subsequently blindly interpreted the same CT identified the T3 fracture or the T10 facet joint widening, although 61% of them did identify the T10 fracture. That the authors showed discord in radiologic interpretation between medical expert witnesses and blinded secondary radiologists interpreting the same images is not at all surprising. The discordance rate of 39% regarding the T10 fracture is not that much out of line with other studies [2, 3]. A discordance rate of 100% relative to the T3 fracture and the T10 facet widening is odd, however. Unfortunately, the authors do not have additional material that might shed light on this oddity. The four expert witnesses who “saw” the three abnormalities on the CT scan presumably testified that the defendant radiologist breached the standard of radiologic care— that is, was negligent—for having missed the findings. In the context of diagnostic radiology, the standard of care calls for radiologists to act reasonably in rendering radiologic interpretations as would ordinary radiologists under the same or similar circumstances. From a strictly legal point of view, the standard of care is not necessarily established by whether the radiologist’s report is correct or incorrect but rather whether it is reasonable. The authors inform us that the malpractice lawsuit focusing on this particular CT was settled, but they were unable to give us any details regarding the patient (e.g., was the patient the wage earner of a family, or did the patient become paraplegic? ) or the defendant radiologist (e.g., did the radiologist “miss” all three findings or just one or two? ). The authors tell us that the inference of “spinal instability,” made by the plaintiff’s expert witnesses who found the facet widening, “was the basis for legal action. ” The word “inference” connotes guesswork based on trivial or inadequate data or premises [4]. In malpractice litigation, opinions of expert witnesses must be couched in a degree of probability that far exceeds inferences; opinions regarding negligence and causes of injury must be “within a reasonable degree of medical certainty,” i.e., greater than 50% likelihood [5]. Many factors are taken into consideration by a jury when determining whether a defendant radiologist is liable and by attorneys representing the opposing litigants when determining whether to settle a lawsuit out of court. Whether the defendant radiologist has missed a radiologic finding and the severity of patient injury are just two of these factors. The authors’ concerns that expert witnesses retained by attorneys may render subjective and biased opinions because they know the clinical outcome and are being paid are real and shared by many radiologists. It is true that medical experts retained by attorneys tend to emphasize only those facts that support the position of the party by whom they have been retained. It is also true that some experts offer distorted opinions regarding the standard of care because of financial considerations or simply because they truly believe that the standard of care is closer to “perfection” than “reasonable. ” The latter may be applicable to the T3 fracture and T10 facet joint widening. The overwhelming majority of radiologists acting as expert witnesses are honest, knowledgeable, and realistic, and they testify in good faith. However, the distinction between honest differences of opinion and opinions indicative of false or biased testimony is far from clear. Expert testimony expressing reasonable differences of opinion about conduct of radiologists is ingrained in the adversarial nature of civil litigation as it is and has been practiced in the United States since the founding of our Republic. Although admittedly our legal system has many faults, some of which were enumerated by Dr. Semelka and colleagues [1], the system is not apt to change. The proposal by Dr. Semelka and colleagues [1] of having a panel of independent, objective radiologists determine whether a defendant radiologist has or has not breached the standard of care may at first glance sound appealing to many radiologists. However, let us be careful what we wish for. I pose the following hypothetical scenario and question to the reader: You are a defendant radiologist who has been accused of missing what you consider to be a very subtle finding on a radiologic study. You are absolutely convinced that you have done nothing wrong and that most radiologists would not have seen or reported the alleged abnormality. Your defense attorney begins searching for a well-qualified radiologist who will support your interpretation and testify as an expert witness on your behalf. The first radiologist with whom your attorney consults says, “I agree that the finding is very subtle and probably most radiologists would not see it, but I saw it and therefore I do not believe I can defend the radiologist. ” Your defense attorney consults with two more radiologists and receives similar responses. He then approaches a fourth radiologist, a well-regarded and highly qualified individual who has testified as a defense expert witness on previous occasions. This radiologist says, “I definitely agree that this finding is extremely subtle, I do not believe that the defendant radiologist was negligent, and I will be glad to testify on the radiologist’s behalf before a jury. ” It is obvious that if the resolution of the lawsuit against you were decided by a panel of the three radiologists first consulted by your defense attorney in this hypothetical case, you would be found liable. However, if the defense attorney were permitted to retain the expert witness, he would have picked radiologist number four, and you would have an excellent chance of prevailing in a jury trial. Which option would you choose? Leonard Berlin NorthShore University HealthSystem Skokie Hospital Skokie, IL