Studdert DM, Mello MM, Sage WM, DesRoches CM, Peugh J, Zapert K, Brennan TA. Defensive Medicine Among High-Risk Specialist Physicians in a Volatile Malpractice Environment. JAMA. 2005;293(21):2609–2617. doi:10.1001/jama.293.21.2609
Author Affiliations: Department of Health Policy
and Management, Harvard School of Public Health (Drs Studdert, Mello, DesRoches,
and Brennan), Department of Medicine, Harvard Medical School (Dr Brennan),
and Department of Medicine, Brigham and Women’s Hospital (Dr Brennan),
Boston, Mass; Columbia Law School, New York, NY (Dr Sage); and Harris Interactive
Inc, Rochester, NY (Mr Peugh and Dr Zapert).
Context How often physicians alter their clinical behavior because of the threat
of malpractice liability, termed defensive medicine,
and the consequences of those changes, are central questions in the ongoing
medical malpractice reform debate.
Objective To study the prevalence and characteristics of defensive medicine among
physicians practicing in high-liability specialties during a period of substantial
instability in the malpractice environment.
Design, Setting, and Participants Mail survey of physicians in 6 specialties at high risk of litigation
(emergency medicine, general surgery, orthopedic surgery, neurosurgery, obstetrics/gynecology,
and radiology) in Pennsylvania in May 2003.
Main Outcome Measures Number of physicians in each specialty reporting defensive medicine
or changes in scope of practice and characteristics of defensive medicine
(assurance and avoidance behavior).
Results A total of 824 physicians (65%) completed the survey. Nearly all (93%)
reported practicing defensive medicine. “Assurance behavior” such
as ordering tests, performing diagnostic procedures, and referring patients
for consultation, was very common (92%). Among practitioners of defensive
medicine who detailed their most recent defensive act, 43% reported using
imaging technology in clinically unnecessary circumstances. Avoidance of procedures
and patients that were perceived to elevate the probability of litigation
was also widespread. Forty-two percent of respondents reported that they had
taken steps to restrict their practice in the previous 3 years, including
eliminating procedures prone to complications, such as trauma surgery, 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.
Conclusion Defensive medicine is highly prevalent among physicians in Pennsylvania
who pay the most for liability insurance, with potentially serious implications
for cost, access, and both technical and interpersonal quality of care.
Defensive medicine is a deviation from sound medical practice that is
induced primarily by a threat of liability.1,2 Defensive
medicine has been reported widely in the United States and abroad.3- 6 However,
its prevalence and characteristics remain controversial.7
Defensive medicine may supplement care (eg, additional testing or treatment),
replace care (eg, referral to another physician or health facility), or reduce
care (eg, refusal to treat particular patients).8,9 Some
practices, herein termed assurance behavior (sometimes
called “positive” defensive medicine), involve supplying additional
services of marginal or no medical value with the aim of reducing adverse
outcomes, deterring patients from filing malpractice claims, or persuading
the legal system that the standard of care was met. Other practices, herein
termed avoidance behavior (sometimes called “negative”
defensive medicine), reflect physicians’ efforts to distance themselves
from sources of legal risk. Defensive medicine, particularly avoidance behavior,
encompasses both day-to-day clinical decisions affecting individual patients
and more systematic alterations of scope and style of practice.
Defensive medicine has mainly been invoked as an argument for tort reform
in the years between malpractice crises when other pressures for legal change
have ebbed.10 Analysts have focused on liability
concerns as contributing incrementally to the overuse of health care services
in the United States and the waste of scarce economic resources.11 We
hypothesized that during a more volatile period in liability insurance markets,
physicians’ uncertainty about the costs and availability of coverage
may induce a wider array of defensive practices, affecting not only the cost
of health care but also its accessibility and quality.12
We queried a group of physicians at high risk of malpractice claims
about the frequency and nature of their defensive practices. These physicians’
liability risk stemmed from location of their practice in Pennsylvania, a
state that has been hit particularly hard by the latest malpractice “crisis.”13 At the time of the study, several liability insurers
had recently left the Pennsylvania market and premiums charged by the remaining
insurers had risen dramatically over the preceding 3 years.13 For
example, the cost of a standard primary-layer policy for Philadelphia general
surgeons at the largest insurer rose from $33 684 in 2000 to $72 518
in 2003, excluding a mandatory contribution to the state’s secondary-layer
insurance fund (amounting to 43% of the primary premium in 2003).14 The physicians we surveyed came from 6 specialties
that have been acutely affected by high rates of litigation and steep premium
increases. We requested specific details of defensive practices undertaken.
We also tested whether the odds of physicians’ practicing defensively
were associated with objective and subjective measures of their liability
Researchers at the Harvard School of Public Health (Boston, Mass) and
Columbia Law School (New York, NY) collaborated with a professional survey
organization, Harris Interactive Inc (Rochester, NY), to design and conduct
the survey. Design of the sample and survey questionnaire was shaped by findings
from 41 in-depth key informant interviews conducted with representatives from
medical specialty societies, county medical societies, hospitals, insurers,
and government agencies in Pennsylvania. Institutional review boards at the
Harvard School of Public Health and Columbia Law School approved the research.
The survey cover letter provided basic information about the study and return
of the questionnaire constituted evidence of informed consent.
Key informants identified 6 specialties—emergency medicine, general
surgery, neurosurgery, obstetrics/gynecology, orthopedic surgery, and radiology—as
being especially affected by high and rising liability costs. A stratified
random sample of 1333 physicians in these specialties was drawn from the American
Medical Association Physician Masterfile; 1 primary stratum consisted of 5
counties in southeastern Pennsylvania, which informants identified as most
affected, and the other consisted of all other counties in Pennsylvania. Within
each stratum, specialists who were active in direct patient care at least
50% of the time according to the Physician Masterfile data were sampled. Sampling
was proportionate by specialty except that neurosurgeons were oversampled
to ensure adequate representation. The sample size was calculated to provide
80% power to detect differences of 10% or higher between specialty groups
at the P<.05 level.
A 6-page questionnaire was developed and pretested on 10 Pennsylvania
physicians in the targeted specialties. Cognitive posttest interviews led
to revision of the questionnaire. The revised questionnaire contained questions
about practice decisions, liability insurance, experience with malpractice
claims, and demographic information. Respondents were asked to rate on a 4-point
scale (never, rarely, sometimes, often) how frequently concerns about malpractice
liability caused them to engage in each of 4 forms of assurance behavior:
(1) order more tests than medically indicated; (2) prescribe more medications
than medically indicated; (3) refer to specialists in unnecessary circumstances;
and (4) suggest invasive procedures against professional judgment. Respondents
used the same scale to rate the frequency with which they practiced 2 forms
of avoidance behavior: (1) avoid conducting certain procedures/interventions;
and (2) avoid caring for high-risk patients. Respondents who reported engaging
in any of these defensive medicine practices were then asked in an open-ended
question to describe their most recent act.
In addition, respondents were asked in consecutive questions whether
they had reduced or eliminated high-risk aspects of their practice in the
last 3 years because of the cost of professional liability insurance in Pennsylvania
and the likelihood that they would (further) do so in the next 2 years. Respondents
who answered affirmatively to either question were asked to specify the change
as an open-ended response.
Following institutional review board approval, the survey was mailed
in May 2003 to 1333 physicians, along with a $75 honorarium. Multiple follow-up
contacts were made with nonrespondents by mail and telephone during June and
July. Physicians were also given the option of completing the survey online;
8% of respondents did so. Sixty-five physicians in the sample were deemed
ineligible (52 no longer involved in direct patient care, 11 relocated out
of state, and 2 deceased). After exclusion of these ineligible physicians,
824 physicians completed the survey—an adjusted response rate of 65%
(824/1268). Specialty-specific response rates were: orthopedic surgeons, 72%;
obstetrician/gynecologists, 67%; emergency physicians, 67%; general surgeons,
66%; radiologists, 59%; and neurosurgeons, 56%. The Physician MasterFile permitted
comparison of respondents with nonrespondents across 5 variables (age, sex,
specialty, years in practice, and hospital affiliation). There were statistically
significant differences between the average age of respondents and nonrespondents
(50 vs 51 years, respectively, P = .008)
and their average years in practice (21 vs 22 years, respectively, P = .02), but the absolute difference in both cases was only
Sampling weights were applied to ensure that survey responses reflected
the distribution of Pennsylvania physicians in direct patient care in the
selected specialties. Data were weighted within each geographic stratum by
specialty, sex, and length of time in practice. Data were further weighted
to make the sample representative of all Pennsylvania physicians in each of
the specialties. All results except for the sample characteristics are presented
in weighted form, although the effect of weighting was negligible. The margin
of error for the study sample was ±4 percentage points and ranged up
to ±17 percentage points in subsample analyses.
The data were analyzed using the SPSS 11.5 (SPSS Inc, Chicago, Ill)
and STATA 7.0 (STATA Corp, College Station, Tex) statistical software packages
with appropriate corrections for the complex survey design. Subgroup comparisons
were made using adjusted Pearson χ2 analysis.
We used conditional logistic regression to analyze predictors of frequent
practice of each of the 6 forms of defensive medicine. The dependent variable
in these analyses was respondents who reported undertaking the relevant practice
“often” compared with all other responses. The paucity of responses
in the “never” and “rarely” categories prompted this
dichotomy. This specification of the dependent variables created relatively
prevalent outcomes of interest, ranging from 32% to 61% across the 6 regression
analyses (mean [SD] of 42% [12%]); therefore, the odds ratios (ORs) produced
by the regression analyses should be interpreted as relative odds not relative
The independent variables were physician characteristics (years in practice,
sex), practice type (solo, group, hospital clinic, other), form of liability
insurance, and 3 objective measures of liability
risk (physicians’ practice location in a high-risk area, dropped by
liability insurer within last 3 years, sued within last 3 years). In addition,
2 subjective measures of the impact of the liability
environment on physician attitudes were constructed from the following questions:
(1) “How much of a financial burden are your professional liability
insurance premiums?” (not at all a burden, minor burden, major burden,
extreme burden); (2) “How confident are you that your current liability
insurance will cover all situations for which you may need coverage?”
(not at all confident, not very confident, somewhat confident, very confident).
Responses to these 2 questions were dichotomized (extreme burden vs other;
not at all/not very confident vs somewhat/very confident), which split respondents
into 2 groups of roughly equal size, and then added to the independent variables.
We tested alternative specifications of both the dependent and independent
The conditional regression design was based on specialty strata. We
constructed the model this way to mitigate the potential for reported frequencies
of each of the forms of defensive medicine behavior to be influenced by interspecialty
differences in physicians’ opportunities to perform those behaviors.
For example, emergency physicians are relatively constrained in their ability
to turn away high-risk patients. Thus, the model estimated predictors by specialty,
with the final estimates representing an overall mean of the intraspecialty
Obstetrician/gynecologists comprised the largest specialty group among
respondents (23%), followed by general surgeons and radiologists (both 19%),
emergency physicians (18%), orthopedic surgeons (15%), and neurosurgeons (6%)
(Table 1). Respondents were fairly seasoned
clinicians (96% with >10 years in practice). They practiced in a mix of medical
groups (39%), hospitals (28%), and solo practices (20%), and obtained their
liability insurance coverage directly from a commercial carrier (63%) or through
a hospital (37%).
Specialist physicians in the sample were not strangers to malpractice
litigation and its consequences. Approximately two thirds practiced in high-risk
regions of Pennsylvania, 88% had previously been sued and 48% had been sued
in the previous 3 years. In addition, 51% had been dropped by an insurance
carrier since 1995. A larger proportion of respondents were dropped after
2000 than between 1995 and 2000, but the primary reason for being dropped
in both periods was that the insurer stopped writing policies for the respondent’s
specialty in Pennsylvania.
Most respondents perceived their insurance premiums to be financially
burdensome, with 41% classifying the burden as extreme. Half of the respondents
lacked confidence that their insurance would provide adequate coverage in
the event they were sued; an additional 42% were somewhat confident and 8%
were very confident.
Virtually all respondents (93%) reported that they sometimes or often
engaged in at least 1 of the 6 forms of defensive medicine outlined in the
survey, and 82% of those who reported practicing defensively (626/768) detailed
their most recent defensive act. Many of the respondents to the survey also
reported that they had restricted the scope of their clinical practice because
of liability concerns (42%) and/or were likely to do so further in the next
2 years (49%).
Fifty-nine percent of respondents reported that they often ordered more
diagnostic tests than were medically indicated; the proportion was significantly
higher for emergency physicians (70%) compared with all other specialists
(Table 2). Fifty-two percent of all
respondents reported that they often referred patients to other specialists
in unnecessary circumstances; this was a particularly common practice among
obstetricians/gynecologists (59%). One third of all respondents reported often
prescribing more medications than were medically indicated, and the same proportion
reported often suggesting invasive procedures which, in their professional
judgment, were unwarranted. General surgeons were especially likely to say
that they often suggested unnecessary invasive procedures (44%).
Table 3 quantifies the specific
practices reported by the 626 respondents who detailed their most recent defensive
act. Forty-three percent of respondents who reported a defensive act, and
more than half of the emergency physicians, orthopedic surgeons, and neurosurgeons
who reported an act, described using imaging studies as their most recent
act. More than half of the emergency physicians, orthopedic surgeons, and
neurosurgeons who reported an act described using computed tomography, magnetic
resonance imaging, or radiography that was not clinically necessary. Among
obstetrician/gynecologists, ultrasonograms were the diagnostic study of choice
(18%), but unnecessary referral (32%) was the most common practice. Eighteen
percent of general surgeons and 9% of obstetrician/gynecologists declared
ordering of an unnecessary biopsy as their most recent defensive act.
A few clinical scenarios arose repeatedly in physicians’ verbatim
descriptions of their defensive practices. Detection of cancer is a major
concern among physicians in all specialties surveyed (157; 24% of specified
practices), which manifested in increased use of diagnostic imaging, specialist
referral, and invasive procedures. Emergency physicians reported performing
extensive workups, including hospitalization, for atypical chest pain in low-risk
patients (22; 16% of practices specified by emergency physicians), ordering
computed tomography for abdominal symptoms unlikely to be acute appendicitis
(15; 11%), and ordering cranial imaging for minor trauma or other questionable
indications (34; 25%). Obstetrician/gynecologists reported ordering ultrasonograms
for both pregnant and nonpregnant patients (7; 4% of practices specified by
obstetrician/gynecologists), and referring patients with palpable breast masses
for surgical biopsy regardless of mammographic findings (9; 5%). General surgeons
reported performing biopsies of breast masses (21; 14% of practices specified
by general surgeons) and ordering confirmatory imaging of appendicitis before
operating or declining to operate (17; 11%). Orthopedists and neurosurgeons
reported ordering magnetic resonance imaging to exclude a tumor diagnosis
for spine, bone, or joint symptoms (13; 7%). Radiologists reported referring
patients with ambiguous mammograms for surgical biopsy (26; 17% of practices
specified by radiologists) and ordering close follow-up with repeat imaging
of low-risk abnormalities on chest radiographs (6; 4%).
Thirty-nine percent of specialist physicians reported that they “definitely
will/already decided to” avoid caring for high-risk patients (Table 2). This response was significantly more
likely among orthopedic surgeons (57%) and significantly less likely among
emergency physicians (13%) compared with all other specialists. One third
of specialist physicians reported often avoiding certain procedures or interventions;
orthopedic surgeons were especially likely to report that they did so often
Among the 425 respondents who detailed their restrictions on practice,
the most common reports were stopping practice altogether or eliminating specific
high-risk procedures (Table 4); for
example, emergency or trauma surgery by orthopedic surgeons, neurosurgeons,
and general surgeons; complex obstetrics by obstetrician/gynecologists; and
mammograms by radiologists. Many surgeons also reported avoidance of patients
perceived to be risky propositions, either because of their clinical complexity
or personal propensity for litigation, such as children and patients covered
by workers’ compensation and medical assistance.
Among respondents’ reports of their most recent act of defensive
medicine, avoidance behaviors were less prominent (Table 3). A substantial number of orthopedic surgeons (19%) and
neurosurgeons (11%) reported referring a patient to another physician; several
general surgeons reported referring a patient to another hospital (6%) or
to another physician (7%). Although referral to another physician was the
most common specific practice reported by obstetrician/gynecologists (32%),
most of those referrals were made in their primary care capacity (eg, evaluation
of breast masses) and therefore represent assurance rather than avoidance
Table 5 shows all statistically
significant predictors of the defensive practices identified in the adjusted
analyses. Two subjective measures of liability experience—specialist
physicians’ confidence in the adequacy of their liability coverage and
their perceptions of premium burdens—were the strongest predictors across
all types of defensive practice. Specialist physicians who lacked confidence
in their coverage were more than twice as likely as other specialists to order
unnecessary diagnostic tests (OR, 2.48; 95% confidence interval [CI], 1.75-3.51),
refer patients to other physicians unnecessarily (OR, 2.25; 95% CI, 1.52-3.05),
suggest invasive procedures that in their clinical judgment were not needed
(OR, 2.12; 95% CI, 1.48-3.04), and avoid risky procedures (OR, 2.26; 95% CI,
1.57-3.26) and high-risk patients (OR, 2.47; 95% CI, 1.72-3.56). Specialist
physicians who perceived their premium burden as extreme were more than 11/2
times as likely as other specialists to overprescribe medication (OR, 1.88;
95% CI, 1.27-2.80), refer patients to other physicians unnecessarily (OR,
1.71; 95% CI, 1.53-2.88), and order unnecessary diagnostic tests (OR, 1.51;
95% CI, 1.02-2.22).
Only 1 of the 3 objective measures of physician liability risk was significant
in any of the 6 regression models: the odds of overprescribing medication
were greater for specialist physicians who had been dropped by their liability
insurer in the previous 3 years (OR, 1.69; 95% CI, 1.18-2.41). Eliminating
the subjective variables from the model did not affect this result.
There was correlation among the outcome measures in the regression models
as they captured different dimensions of defensive practice. Applying a Bonferroni
correction for multiple comparisons dropped extreme premium burden from statistical
significance as a predictor of overtesting; however, it did not affect the
significance of the subjective measures in any other analyses.
Findings from the regression analyses were robust to alternative specifications
of the dependent and independent variables. Respecifying the dependent variables
as often/sometimes compared with rarely/never had only a minor impact on the
size of coefficients; it also added extreme premium burden as a significant
predictor of avoiding interventions (OR, 1.64; 95% CI, 1.08-2.50) and high-risk
patients (OR, 1.58; 95% CI, 1.05-2.39). Altering the specification of the
variable capturing lack of confidence in coverage (not at all vs the rest)
had a trivial impact on size of coefficients and added the premium burden
as a significant predictor of invasive procedures (OR, 1.50; 95% CI, 1.02-2.21).
The distribution of responses within the premium burden variable did not permit
stable alternatives for specification.
We also regressed a composite outcome variable on the original set of
independent variables. This outcome variable compared respondents who reported
often engaging in 3 or more of the 6 behaviors (n = 301) with the
rest of the sample. Three predictors were statistically significant: lack
of confidence in coverage (OR, 2.28; 95% CI, 1.63-3.20), extreme premium burden
(OR, 2.01; 95% CI, 1.38-2.93), and 30 or more years in practice (OR, 1.65;
95% CI, 1.08-2.52).
Previous efforts to measure defensive medicine have used either surveys
of clinicians about their behavior3 or linkage
of variation observed in practice patterns to variation in liability exposure.5,16- 18 Each
approach has methodological strengths and weaknesses.2,3 We
sought to advance survey work in this area in 3 ways. First, many previous
surveys have centered on physicians subjected to relatively low levels of
litigation, placid malpractice environments, or both.5,19- 24 Second,
the research has often been limited to single specialties, such as obstetrics.18,25- 30 Third,
most questionnaires have measured defensive medicine using fixed, generic
categories or predetermined scenarios,3 lacking
self-reported detail about specific behaviors.
We investigated defensive medical practice within a state that has been
significantly affected by the latest escalation of liability costs and surveyed
the 6 specialties that pay the most for liability insurance. We supplemented
queries about classic forms of defensive practice with an open-ended format
designed to distinguish general sentiment from actual conduct, and to elicit
specific details of defensive acts.
We found that defensive medicine was widespread among high-risk specialists
practicing in Pennsylvania, with 9 of 10 respondents reporting defensive practices.
Overordering of diagnostic tests, unnecessary referrals, and avoidance of
high-risk patients were the most common forms; three quarters of respondents
said that they engaged in at least 1 of these defensive practices “often.”
Discrepant questionnaire wording frustrates neat comparisons across studies
and our study does not correlate longitudinal changes in defensive practices
with changes in the liability environment, but the frequencies reported in
our study dramatically exceed those found in previous research. This suggests
that physicians’ practices may be sensitive to swings in the litigation
and insurance climate.
In our study, as in previous ones, objective measures of physicians’
liability experience and exposure were not associated with individual physicians’
propensity to practice defensively.24,28,31- 33 In
explaining this phenomenon, Glassman et al31 have
suggested that “the signal to practice defensively may have been broadcast
so widely that individual experience is overshadowed by collective anxiety.”
Personal anxiety may also overshadow actual experience. We found that 2 subjective
measures—confidence in liability coverage and burdensomeness of insurance
premiums—were associated strongly with higher odds of individual physicians
practicing virtually all forms of defensive medicine. Attention to the psychological
effects of the liability environment seems particularly apt in the current
liability environment. Tighter reimbursement rates, more assertive patients,
greater administrative burdens, increased likelihood of being dropped by liability
insurers, and other challenges to physicians’ equanimity tip physicians
into a defensive posture that liability risk alone might not provoke.34
Many specialist physicians reported doing more for (or to) patients
because of malpractice risk, the cost of which is mainly borne by health insurance.
Resorting to unnecessary diagnostic tests, especially imaging, was extremely
common and cut across specialties. More than 90% of all respondents reported
ordering tests unnecessarily and more than 60% of physicians in all specialties
except neurosurgery reported performing or requesting invasive diagnostic
procedures. Within the group of physicians who practiced defensively, 70%
reported ordering an unnecessary diagnostic test as their most recent act.
The prevalence of assurance behavior, coupled with the unit of cost procedures
typically ordered (eg, MRIs), lends weight to arguments that the total cost
of defensive medicine is substantial.
Technology plays a key role in defensive medicine, and in malpractice
liability generally.34 Specialists reported
using technology to pacify demanding patients, bolster their own self-confidence,
or create a trail of evidence that they had confirmed or excluded particular
disease entities. For example, assurance behavior in our study often involved
cancer diagnoses in younger patients who had consulted obstetrician/gynecologists
or orthopedists. Advances in diagnostic and therapeutic technologies make
early detection of cancer both feasible and beneficial, and increase the likelihood
that a missed diagnosis will be ruled negligent and assessed substantial damages.
Defensive use of technology is self-reinforcing. 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. Reforms to address such
“intensity creep” might include practice guidelines that empower
physicians to withhold low-yield tests or force patients to shoulder some
of the financial burden as well as dispute resolution and compensation systems
that reduce hindsight bias following injury. Professional organizations are
well positioned to lead the development and diffusion of such guidelines.
Effects of defensive medicine on patients’ access to care are
difficult to demonstrate because multiple factors influence access and few
benchmarks exist for optimal supply (M.M.M., D.M.S., C.M.D., et al, unpublished
data, 2004).35 Nonetheless, large numbers of
respondents reported engaging in avoidance behavior, many reporting across-the-board
reductions in their scope of practice to qualify for less expensive malpractice
insurance. For example, obstetrician/gynecologists reported halting obstetrics
and radiologists reported not interpreting mammograms, both of which may affect
essential health services for women. Some surgeons appear to be limiting their
practices to “bread-and-butter” operations, no longer performing
more difficult procedures. Several respondents described avoiding sicker patients,
patients with prior complications, and patients perceived as dissatisfied
(including those who had filed lawsuits in the past). When specialists in
rural areas (13% of the sample) engage in avoidance behavior, a substantive
effect on access is more likely because alternative sources of care are limited.
Defensive medicine may reduce or improve quality, depending on the circumstances.36 Most assurance behaviors described, such as additional
diagnostic testing, were not harmful to patients and perhaps even offered
marginal benefits. Referral of difficult cases to more specialized physicians
or better equipped hospitals may be quality-enhancing.
On the other hand, unnecessary invasive procedures create significant
risks of patient harm. Many specialist physicians in our study described performing
biopsies or referring patients for a biopsy for defensive reasons. Because
breast cancer was the most common clinical circumstance in which this occurred,
female patients appear to bear a considerable portion of incremental risk
from defensive medicine. False-positive results associated with low-yield
diagnostic testing may also have detrimental effects on quality, particularly
when ambiguous findings produce emotional distress and necessitate additional
invasive or hazardous procedures.
Defensive medicine takes a toll on interpersonal quality of care and
the patient-physician relationship. Some physicians may spend additional time
with patients and provide more complete information about treatment risks
and alternatives because of malpractice risk, but others may react with suspicion,
confrontation, and abandonment. Our study suggests that certain types of patients
commonly prompt specialist physicians to behave defensively, especially those
who are seen as demanding, emotional, or unpredictable. Safety campaigns that
urge patients to Speak Up37 should take these
effects into account.
Two contrasting behavioral responses were evident. Specialists who perceived
or anticipated adversarial relationships with patients often indulged their
demands for expensive but unnecessary diagnostic studies. However, specialists
also reported refusing to care for patients with prior complications (especially
if they had expressed dissatisfaction with a previous physician), noncompliant
patients, workers’ compensation cases, and obese persons. Both behavioral
responses entail considerable time and energy spent predicting patients’
possible litigiousness, especially for new patients, reflecting a level of
suspicion that itself is arguably detrimental to quality.38
Our study has several limitations. First, measurement and self-identification
of defensive medicine are difficult because distinctions between inappropriate
and appropriate care are not clear in many clinical situations.39 Moreover,
it can be difficult to disentangle liability-related motivators from other
factors that influence clinical decision making, such as physicians’
general desire to meet patients’ expectations, preserve trust, and avoid
the extent that physicians unconsciously practice defensively, our results
will underestimate defensive medicine; to the extent that physicians attribute
liability motivations to decisions driven primarily by other considerations,
our findings will be exaggerated.
Second, physician self-reports of defensive medicine may be biased toward
giving a socially desirable response or achieving political goals. This may
lead respondents to overstate the frequency of forms of defensive medicine
that seem wasteful but not harmful, while causing them to understate the frequency
of potentially dangerous practices. Third, our findings are derived from 6
physician specialties in a single state with a highly stressed liability insurance
system, and may not be generalizable to other locations or malpractice climates.
Higher levels of defensive medicine are part of the social costs of
instability in the malpractice system. The most frequent form of defensive
medicine, ordering costly imaging studies, seems merely wasteful, but other
defensive behaviors may reduce access to care and even pose risks of physical
harm. Because both obstetrics and breast cancer detection are high-liability
fields, women’s health may be particularly affected. Efforts to reduce
defensive medicine should concentrate on educating patients and physicians
regarding appropriate care in the clinical situations that most commonly prompt
defensive medicine, developing and disseminating clinical guidelines that
target common defensive practices, and reducing the financial and psychological
vulnerability of individual physicians in high-risk specialties to shocks
to the liability system.
Corresponding Author: David M. Studdert,
LLB, ScD, MPH, Department of Health Policy and Management, Harvard School
of Public Health, 677 Huntington Ave, Boston, MA 02115 (firstname.lastname@example.org).
Author Contributions: Dr Studdert had full
access to all of the data in the study and takes responsibility for the integrity
of the data and the accuracy of the data analysis.
Study concept and design: Studdert, Mello,
Sage, DesRoches, Peugh, Zapert, Brennan.
Acquisition of data: Studdert, Mello, DesRoches,
Analysis and interpretation of data: Studdert,
Mello, Sage, Brennan.
Drafting of the manuscript: Studdert, Sage.
Critical revision of the manuscript for important
intellectual content: Studdert, Mello, Sage, DesRoches, Peugh, Zapert,
Statistical analysis: Studdert, DesRoches.
Obtained funding: Studdert, Mello, Sage.
Administrative, technical, or material support:
Study supervision: Studdert, Brennan.
Financial Disclosures: None reported.
Funding/Support: This study was funded by grant
2002-00279 from the Pew Charitable Trusts as part of the Project on Medical
Liability in Pennsylvania.
Role of the Sponsor: The funding organization
had no role in the design or conduct of the study; the collection, management,
analysis, or interpretation of the data; or the preparation review, or approval
of the manuscript for submission.
Acknowledgment: We thank Atul Gawande, MD,
MPH, and John Orav, PhD, for helpful comments on an earlier draft of this