Published 1/1/2007
Paul A. Manner, MD

Practicing defensive medicine—Not good for patients or physicians

Recently, several studies have focused on the effects of “defensive medicine” on physicians and patients. In addition, calls for tort reform hold that the practice of defensive medicine is a major factor increasing the cost of medical care. Although the concept of defensive medicine seems obvious, a true estimate of its costs and impact is surprisingly hard to find.

What is defensive medicine?

The Congressional Office of Technology Assessment (OTA) provided a useful definition of defensive medicine in 1994.

“Defensive medicine occurs when doctors order tests, procedures, or visits, or avoid high-risk patients or procedures, primarily (but not necessarily or solely) to reduce their exposure to malpractice liability. When physicians do extra tests or procedures primarily to reduce malpractice liability, they are practicing positive defensive medicine. When they avoid certain patients or procedures, they are practicing negative defensive medicine.”

The OTA also noted that actions may be defensive medicine even if performed for reasons such as a belief in a procedure’s effectiveness, a desire to reduce medical uncertainty, or a financial incentive, provided that the primary motive is to avoid malpractice risk. Also, the motive need not be conscious. Some medical practices become so routine that physicians are unaware that liability concerns originally motivated their use.

Although political or media references to defensive medicine almost always imply unnecessary and costly procedures, OTA’s definition does not exclude practices that may benefit patients. Rather, OTA concluded that a high percentage of defensive medical procedures are ordered to minimize the risk of being wrong when the medical consequences of being wrong are severe.

Concerns regarding malpractice liability thus push physicians’ tolerance for uncertainty associated with medical outcomes to very low levels. These concerns drive doctors to order tests, procedures, and specialist consultations even if the expected benefits are quite small. Using such medical technologies and services to reduce risk to the lowest possible level is likely to be very costly even when the price of the procedure is low. For every case where its performance makes the life-or-death difference, there will be many more cases where its performance is clinically inconsequential.

How prevalent is defensive medicine?

Accurate measurement of defensive medicine is extremely difficult. There are only two ways to estimate whether and how frequently procedures are used for defensive reasons: asking physicians directly in surveys, or linking differences in their actual procedure utilization rates to differences in their risk of liability.

Both of these approaches have serious limitations. As the OTA points out, “if physicians are asked how often they practice defensive medicine in survey questionnaires, they may be inclined to respond with the answer most likely to elicit a favorable political response and thus exaggerate their true level of concern about malpractice…[O]n the other hand, without listed reasons from which to choose, physicians may respond as if the survey is a medical board examination and justify their choices on purely clinical grounds when other factors do in fact operate.”

Looking simply at differences in utilization rates, however, may not reflect differences in patient populations. In addition, because this approach cannot accurately assess the generalized “baseline” level of defensive medicine that may exist in all physicians’ practices, it will only detect incremental differences. Thus, if all physicians are practicing a certain degree of defensive medicine, differences between locales with high versus low malpractice rates will consistently understate the true rate.

Recently, however, a number of authors have identified hard data for the prevalence of defensive medicine. A survey of 300 physicians, 100 nurses, and 100 hospital administrators found that more than 76 percent of the physicians responded that malpractice litigation had hurt their ability to provide quality care to patients. Because of their fear of the excesses of the litigation system:

  • 79 percent said they had ordered more tests than they would have based only on professional judgment of what was medically needed, and 91 percent had noticed other physicians ordering more tests
  • 74 percent had referred patients to specialists more often than they believed was medically necessary
  • 51 percent had recommended invasive procedures such as biopsies to confirm diagnoses more often than they believed were medically necessary
  • 41 percent said they had prescribed more medications, such as antibiotics, than they would have based only on their professional judgment, and 73 percent had noticed other doctors prescribing medications similarly

A large majority of nurses (66 percent) and hospital administrators (84 percent) who participated in the survey reported that unnecessary or excessive care was provided due to fear of litigation.

In 2005, Katz and others showed that malpractice fear accounted for significant variability in emergency department decision-making and was associated with increased hospitalization of low-risk patients and increased use of diagnostic tests. Emergency physicians with high levels of fear of malpractice were less likely to discharge low-risk patients compared with emergency physicians with lower levels of concern. This study also showed no difference in rates of missed acute coronary syndrome, showing that clinical acumen was not different between groups.

In Pennsylvania, a state notorious for its malpractice litigation climate, Studdert et al. studied more than 800 physicians and found that “nearly all” (93 percent) reported practicing defensive medicine. “Assurance behaviors” such as ordering tests, performing diagnostic procedures and referring patients for consultation was very common (92 percent). Among practitioners of defensive medicine who detailed their most recent defensive act, 43 percent reported using imaging technology in clinically unnecessary circumstances.

Avoidance of procedures and patients perceived to elevate the probability of litigation also was widespread; 42 percent of respondents reported that they had taken steps to restrict their practice in the previous three years, including eliminating procedures such as trauma surgery that are prone to complications, and avoiding patients who had complex medical problems or were perceived as litigious. Defensive practice correlated strongly with respondents’ lack of confidence in their liability insurance and perceived burden of insurance premiums.

How much does defensive medicine cost?

Not surprisingly, the true cost of defensive medicine is hard to discern. Kessler and McClellan noted that limits on noneconomic damage awards, such as those California has had in effect for 25 years, can reduce health care costs by between 5 percent and 9 percent without “substantial effects on mortality or medical complications.” Applying noneconomic damage limits to the country as a whole, with its national health care expenditure of $1.4 trillion, would reduce healthcare costs by as much as $126 billion, and reduce the federal government’s share of such costs by as much as $50 billion, according to McClellan’s 2003 estimate.

A study in 2006 by Price Waterhouse Coopers, performed for America’s Health Insurance Plans, estimated that costs associated with medical liability account for between 7 percent and 11 percent of health insurance premium dollars; direct costs of litigation and widespread practice of defensive medicine increase healthcare spending by 10 percent, with a disproportionate increase in outpatient and physician costs. Hellinger and Encinosa found that laws limiting malpractice payments lower state health care expenditures by between 3 percent and 4 percent.

The Congressional Budget Office, however, pointed out in its early 2006 study that a reduction in costs resulting from defensive medicine might be offset by other factors, stating “…there are several possible paths by which medical services utilization could be affected by tort limits. The amount of positive defensive medicine (services provided primarily to avoid being sued for malpractice) might decline. Negative defensive medicine might be reduced as well, meaning that medical providers might be more willing to perform risky procedures; this could increase certain types of utilization. If medical providers were less likely to be sued, they might also feel less compelled to document and justify their clinical decision-making processes, which could reduce the amount of time required to provide a given clinical service. If they faced lower medical malpractice premiums, older physicians might choose to retire later, and younger physicians might be more likely to choose specialties, such as obstetrics, that today typically have a high risk of malpractice litigation. Those possible behavioral responses might increase the supply of physicians, which would tend to decrease prices paid for physicians’ services and increase the volume of such services, with ambiguous implications for health care utilization and spending. Medical providers might also put less effort into conforming to the standard of care, which could increase the rate of medical injuries resulting from negligence. An increase in the rate of such injuries could increase utilization and spending, if those injuries resulted in costly treatments.”

What about the future?

The effects of practicing defensive medicine are not limited to increasing the costs of the delivery of care. Defensive medicine, whether due to a positive or a negative motivation, affects patients as well as physicians. As the OTA pointed out, “Predicting the impact of any malpractice reform on defensive medicine is very difficult, because there is little understanding of which specific aspects of the malpractice system actually drive physicians to practice defensively. Is it simply distaste for having one’s clinical actions called into question? Is it distaste for having one’s actions judged by lay juries? Is it a desire to avoid court trials? Is it a fear, however unfounded, of being financially ruined? Or is it the belief that the legal standard of care is so capricious that the system offers no clear guidelines for how to avoid liability?”

Physician and provider supply

In Pennsylvania, Mello and Kelly reported that a third of residents in obstetrics/gynecology planned to leave the state at the end of their training due to the lack of availability of affordable malpractice coverage. Malpractice costs were cited three times more often than any other factor in this decision.

In Florida, a study earlier this year reported that the state’s medical malpractice climate is discouraging medical students from pursuing careers in obstetrics and gynecology—a trend that could further reduce patients’ access to obstetric care.

The legal system has recently addressed several instances of medical error as criminal matters, including a case of erroneous medication administration by a registered nurse and a case of error in triage in an emergency department. Both instances resulted in patient death, and each resulted in charges of criminal negligence or involuntary manslaughter. The prospect of criminal indictment and potential incarceration and financial ruin (since fines in criminal cases presumably would not be covered by liability insurance), is chilling for providers, and is unlikely to result in a greater willingness to assume care with higher risk.

Utility of increased monitoring and testing

All those involved in the healthcare system, including providers, patients, governments, and payors, would presumably accept higher levels of monitoring and testing if such actions guaranteed better results. Unfortunately, there is little to suggest that this is the case. Although risks from anesthesia have been dramatically reduced through better intraoperative surveillance, including improved technology such as capnometry and pulse oximetry, there is no evidence that this increased reliance on more aggressive monitoring and intervention is applicable across all fields of medicine.

Some plaintiff’s attorneys, for example, have asserted that fetal monitoring and reliance on emergency cesarean section play a key role in reducing the chances of cerebral palsy as the result of birth injury. Recent studies, however, have shown no benefit of any kind, with Clark and Hankins stating that “the rate of cerebral palsy has not decreased in developed countries over the past 30 years, despite the widespread use of electronic fetal heart rate monitoring and a five-fold increase in the cesarean delivery rate over the same period of time.” Graham et al point out that “meta-analysis of the randomized controlled trials comparing EFM [electronic fetal monitoring] with auscultation have found an increased incidence of cesarean delivery and decreased neonatal seizures but no effect on the incidence of cerebral palsy or perinatal death.”

Using a liability-effectiveness model, Pauker and Pauker have shown that “when physicians attempt to avoid liability by practicing defensive medicine, some patients will experience decrements in expected health, but no patients experience increments in expected health,” while Dekay and Asch note that defensive testing reduces the overall quality of patient care.

In an editorial in the Journal of the American Medical Association, Budetti notes, “Perhaps the greatest irony is that defensive medicine may be counterproductive and actually might increase malpractice risk. Studdert and colleagues suggest that ‘the more physicians order tests or perform diagnostic procedures with low predictive values or provide aggressive treatment for low-risk conditions, the more likely such practices are to become the legal standard of care.’…[U]nnecessary invasive procedures and surgery are themselves potentially serious violations of the standard of care and could be the basis for malpractice litigation.”

The current climate of high professional liability is a detriment to good patient care. Defensive medicine provides no benefit and much harm.


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Paul A. Manner, MD, is a member of the AAOS Medical Liability Committee. He can be reached at paulmanner98@yahoo.com