Practice Guidelines and Malpractice Litigation: A Two-Way Street

Methods

Review of Litigation Files

We reviewed files of open and closed claims at two professional liability insurance companies in the United States, one in the northeast and the other in the intermountain west. In the states in which these companies are located, the statute of limitations for malpractice is 2 years and the mean period between date of injury and the date a claim was opened was less than 2 years. One company is physician-owned and provides primarily physician insurance throughout an entire state. The other is a large self-insurer of a group of hospitals and the physicians who practice at those hospitals. Because both open and closed claims were being evaluated, confidentiality concerns were substantial. Therefore, claims from both companies were pooled without any company identifiers attached.

We requested 150 litigation files from each company. Because we thought that practice guidelines might play an important role in anesthesia and obstetrics claims, we requested all such claims that were opened as far back as 1987. We also requested a random sample of claims opened in the years 1989, 1990, and 1991. Our sampling strategy was dictated by our belief that practice guidelines were more likely to be used in more recent claims. On the other hand, we did not want the most recent claims because their files would often be incomplete.

We reviewed the files using a survey instrument with primarily closed-ended, multiple-choice responses. The instrument was initially validated on a test set of claims files. The reviewers searched for references to guidelines in briefs, interrogatories, depositions, and other material in the files. They also noted the specific uses to which the guidelines were put and the parties invoking the guidelines, and they assessed the guidelines' weight in the litigation using structured, implicit judgment techniques.

The reviews were done by three investigators. All of the reviews at one company and more than half of those at the other company were done by a physician who is also a lawyer and who has experience reviewing claims files. The rest of the reviews were split between an investigator who is both a physician and a lawyer and who is experienced in claim reviews and another who is a lawyer with substantial malpractice experience. All data points were keypunched, double-checked for errors, and entered into a SAS data set file.

Survey of Attorneys

To identify attorneys who devote a substantial amount of time to personal injury litigation, we searched a standard national directory of lawyers. All lawyers who had specified medical malpractice as an area of interest, a total of more than 9500, were identified. We then randomly selected 980 of these lawyers from all 50 states.

In January 1993, we mailed each of these attorneys a questionnaire that was 4 pages in length. We requested information on the nature of the attorney's (or his or her firm's) practice; on the attorney's familiarity with the concept of practice guidelines as defined by the Institute of Medicine; and on the use of such guidelines in litigation. Most of the questions were closed-ended, but free-text responses were also captured. A second mailing was done 1 month after the first. All data points were keypunched, double-checked for errors, and entered into a SAS data set file.

Analytic Methods

Univariate proportions, such as the proportion of lawyers using practice guidelines, and their estimated standard errors were calculated using the SAS Proc Means program [15] (SAS Institute, Cary, North Carolina). The Fisher two-tailed exact test was used to examine associations between pairs of variables: for example, the association between the use of practice guidelines in a claim and the teaching status of the hospital in which the claim originated [16]. If one or both of the variables was an ordered categorical variable, the Mantel-Haenszel test statistic was used to test for association [17]. If both variables are ordinal, then using the Mantel-Haenszel test statistic is similar to testing whether a Spearman rank correlation coefficient equals 0 (under the null hypothesis of no association) [18]. These statistics and their corresponding P values were obtained using SAS Proc Freq. For a few tables, exact test statistics for associations between a pair of ordered categorical variables were used if the sample size of a contingency table was small; this was done using the STATXACT statistical package [19] (Cytel, Cambridge, Massachusetts).

For binary outcomes, such as the use of practice guidelines, logistic regression was used for multivariate analyses: for example, to simultaneously identify significant predictors of the use of practice guidelines. For ordinal categorical outcomes, such as the average number of malpractice cases in which practice guidelines were used (categorized as 0, 1, 2 to 5, 6 to 10 and >10), proportional odds logistic regression was used for the multivariate analysis [20]. The logistic regression and proportional odds logistic regression estimates were obtained using SAS Proc Logistic software. The interpretation of the regression coefficients from the proportional odds logistic regression model is similar to the interpretation of the parameters from the usual logistic regression model.

Results

Review of Litigation Files

Overall, 130 cases were obtained from one insurance company; the other 20 cases were not located in the time available for review. At the second insurance company, we reviewed 129 cases selected randomly from the 150 cases available. This produced a total of 259 claims. Many of the more recent claims were missing information about multiple entries. Seven files were too incomplete to be classified.

The event year for claims ranged from 1976 through 1991; it was usually between 1986 and 1989 (n = 181; 69.9%) (Table 1). At the time of review, 42 (16.7%) of the claims had been closed with no payment and 111 (44%) had been settled with payment. Ten cases (4%) had gone to a jury and 89 (35.3%) were still open. In the three verdicts for plaintiffs, the awards were greater than $1 000 000. Two thirds of the cases settled were settled for less than $300 000; the mean settlement amount was $327 045.

Most of the claims originated in physicians' offices (30.2%) or in the operating room (28.6%). Many were brought against physicians in private practice settings (58.3%). Although the type of adverse event was unclassifiable or missing in 44 cases, 33% of claims involved diagnostic error and 28% involved operative complications. Claimants were primarily insured commercially; Medicare recipients accounted for only 6.5% of claims and Medicaid recipients for only 4.5%. The primary defendant ranged from having just recently started practice to having been in practice more than 20 years. Forty-one percent of claimants had had a relationship of less than 1 year with the defendant physician and 10% had had a relationship of more than 3 years with the defendant.

The reviewers classified a claim as involving a practice guideline if, in their judgment, the guideline was relevant to and played a pivotal role in the proof of negligence. Only 17 of 259 claims involved the use of practice guidelines (6.6%); these were used for inculpatory purposes in 12 cases and for exculpatory purposes in 4 cases. One use of guidelines could not be classified. Eight of those cases in which guidelines were used for inculpatory purposes resulted in settlement with payment for the plaintiff, 2 are still open, 1 was closed with no payment, and 1 resulted in a jury verdict for the defendant. Among those cases in which guidelines were used for exculpatory purposes, 1 resulted in a jury verdict for the plaintiff, 1 resulted in a settlement with payment for the plaintiff, and 2 are still open. Guidelines were used for inculpatory purposes in 9 of 10 settled cases. In a case that resulted in a verdict for the defendant, the plaintiff used a guideline for inculpatory purposes; on the other hand, a verdict for a plaintiff involved exculpatory use of a guideline by the defendant (Figure 1).

Few factors were associated with use of practice guidelines. None of the following was significantly associated with use of practice guidelines: years of physician practice, primary professional activity, size of law firm defending or bringing the case, experience in years of primary plaintiff or defendant attorney, type of adverse event, open or closed status of the case, claim year, settlement amount, or the fact that the defendant was a hospital.

Several factors showed a trend toward significant association with use of practice guidelines. Practice guidelines were used as inculpatory evidence in 2 of 8 cases brought in nonteaching hospitals and in 3 of 67 cases brought in teaching hospitals (Fisher exact test, P = 0.148). Two of 7 claims brought in hospitals with fewer than 8000 discharges per year involved inculpatory use of practice guidelines; only 3 of 57 claims arising in hospitals with more than 16 000 discharges per year included inculpatory use of practice guidelines (Fisher exact test, P = 0.114).

The only factor that showed a significant association with use of guidelines was length of physician relationship. Physicians who had a longer relationship with a particular patient were more likely than other physicians to have claims that involved practice guidelines (Fisher exact test, P = 0.021). All six cases in which the patient–physician relationship had existed for more than 1 year were based on the inculpatory use of guidelines. The outcome variable of interest, use of practice guidelines, was too sparse to support a multivariate analysis.

Seven claims involved obstetrics guidelines (13.4% of 52 obstetrics cases) and four involved family practice (16% of 25 family practice cases). All of the family practice claims involved labor and delivery problems. No other single specialty, including anesthesia, had more than one claim involving a guideline.

Survey of Attorneys

A total of 980 surveys were mailed and 20 were returned as undeliverable, leaving 960 for analysis. In the first round of mailings, 357 surveys were returned. In the second, 221 were returned, for a total of 578. The overall response rate was therefore 60.2% (Figure 2). Respondents did not differ from nonrespondents or from the entire pool of attorneys in age, size of firm, or geographic location (the only parameters available for the entire data set). The only parameter for which the first round of respondents differed from the second round was the average number of new malpractice cases the respondents initiated per year: Fifty-eight percent of respondents in the first round initiated more than five new cases per year compared with 49% of those in the second round (P = 0.048).

Thirty-five respondents reported that they had not worked on a malpractice case in the previous 3 years; they were excluded from the analysis. Including them did not significantly change the results reported here. Another 144 respondents reported that they were unaware of the concept of practice guidelines as defined by the Institute of Medicine, and so were excluded from multivariate analyses. The respondents who were unaware of the concept of practice guidelines were significantly less likely to spend more than half of their time on medical malpractice cases and significantly less likely to work at a firm in which most cases involved medical malpractice.

Two hundred and ninety-three (54%) respondents primarily represented plaintiffs (Table 2). More than two thirds of respondents said that more than 20% of their work was in medical malpractice, and 43% spent more than half of their professional time in this area. More than 90% had had more than 5 years of experience in litigation. Forty-five percent of respondents initiated one to five new malpractice cases per year, and 55% initiated more than five. The respondents were therefore an experienced and seasoned group of litigators.

As noted, almost three fourths of the attorneys were aware to some degree of the concept of practice guidelines. Although 48.1% had had at least one case per year in which guidelines played a role, only 36.3% of attorneys had had one case per year in which guidelines played an important role (Table 3). One hundred and seventy-eight attorneys perceived guideline use to be increasing, whereas only 7 thought it was decreasing.

Guidelines also appear to affect litigation. More than 27% of attorneys reported that a guideline had influenced their decision to settle a case and 22% stated that a guideline had influenced the trier of fact in a case in the previous year. Perhaps more importantly, guidelines affect plaintiffs' attorneys' decisions about which cases to bring: A total of 26.2% of plaintiffs' attorneys reported that guidelines had been influential at least once in the previous year in a decision not to take a case, whereas 30.9% reported that a guideline influenced their decision to bring at least one case in the previous year. Experience with practice guidelines was also prevalent among defense attorneys; 38.4% of defense attorneys reported that guidelines had been important in more than one case in the previous year.

Defense attorneys' experiences with guidelines were often reactive: The attorney had to counter a guideline that had been used for inculpatory purposes by the plaintiff's attorney. Indeed, the respondents noted that 54% of their individual cases that involved a guideline also involved care that departed from a guideline, and 23% involved care that complied with a guideline. In 23% of cases, the use of guidelines was disputed. The leading sources of guidelines were the American College of Obstetricians and Gynecologists (28.4%), hospital procedures and protocols (22.7%), the Joint Commission for Accreditation of Health Care Organizations (6.8%), and the American Medical Association (6.8%).

Guidelines do not appear to influence the need for medical experts. Only 4.7% of attorneys reported that a guideline decreased the need for an expert, 11.8% said it increased the need for an expert, and the rest said it had no effect. Often, attorneys had to use experts to enter guidelines into evidence. Opposing attorneys had to hire experts to rebut guidelines. No attorneys reported that guidelines had been dismissed through a modified locality rule.

In univariate analyses, the only characteristic of attorneys that was associated with more frequent use of practice guidelines was a practice in which more than 50% of the total case load was in medical malpractice. Forty-one percent of attorneys whose work was primarily in medical malpractice had had more than one case in which a practice guideline played a role, whereas only 26.6% of other attorneys had had more than one such case (P = 0.0003). Multivariate analyses showed the same result.

Discussion

As measured by our litigation file review and our survey of attorneys, malpractice insurers and plaintiffs' attorneys presently make modest use of practice guidelines in litigation. Most attorneys are aware of the concept of guidelines. Nearly half have had a case in which a guideline played a role and one third have had a case in which a guideline played an important role. One fourth of all attorneys state that a guideline influenced their decision to settle a case, and one fourth of plaintiffs' attorneys report that a guideline led them to refuse a case. If guidelines lead to reductions in rates of inappropriate suits or to more expeditious resolution of such suits, then they will play a valuable role in malpractice litigation.

The overwhelming proportion of respondents think that the use of guidelines is increasing. The only characteristic of attorneys that was associated with use of practice guidelines was doing a greater proportion of work in medical malpractice. These attorneys are the “malpractice professionals” and are probably the opinion-leaders in the field. It would appear, then, that the concept of guidelines is spreading evenly throughout the profession, led by the experienced attorney, and that we can expect more use of guidelines in litigation.

Few of the characteristics of any particular case seem to predict the use of practice guidelines. Guidelines may be used more frequently in claims involving nonteaching or small hospitals. We hypothesize that these hospitals are more likely to produce injuries in which care failed to meet a widely followed practice standard, but our information is too incomplete to confirm this.

Guidelines were used more frequently in cases in which a plaintiff sued a physician with whom the plaintiff had a relatively long-term relationship. This may suggest that patients are unlikely to sue their long-time physicians unless the care they received clearly failed to meet a standard reasonably expected of the medical practitioner, as shown by violation of a guideline. It appears that clearer evidence of negligence provided by transgression of a practice guideline may overcome barriers to suit.

Those from the American College of Obstetricians and Gynecologists are the most frequently used of all practice guidelines. Indeed, 11 of the 17 cases that we uncovered that involved practice guidelines also involved obstetrics. These guidelines are relatively well known to the plaintiff and the defense bar and are applicable in numerous cases. Anesthesia, by contrast, was involved in few cases, even though the American Society of Anesthesia guidelines have been widely disseminated [21].

The difference between anesthesia and obstetrics guidelines may indicate the factors that will determine how and how frequently guidelines are used. When physicians comply with guidelines, the exculpatory value of those guidelines will likely dissuade plaintiffs' attorneys from bringing cases. When physicians fail to comply, plaintiffs' attorneys will use the guidelines as evidence of negligence. When the standards are simple and clearly defined, as they are in anesthesia, compliance is likely to be higher. When the standards define only part of a complicated care process, as those from the American College of Obstetricians and Gynecologists do, compliance may be lower, and the guidelines are likely to be implicated in many claims.

Our most significant finding is that guidelines are clearly being used for both inculpatory and exculpatory purposes. Among the 17 cases that we uncovered in which practice guidelines were used, guidelines were used for inculpatory purposes more than twice as often as they were used for exculpatory purposes. Survey respondents also reported that among filed cases, inculpatory use is more frequent than exculpatory use. But this is counterbalanced by the fact that exculpatory guidelines induce attorneys not to bring cases.

This information should be noted carefully by health reformers who invoke guidelines as a form of relief for professional liability. State plans in Maine and Minnesota [22] indicate that physicians can use guidelines for exculpatory purposes—in Minnesota, as an absolute bar to liability—but plaintiffs may not use the guidelines for inculpatory purposes.

Such one-way use of guidelines is at odds with the two-way use of guidelines that presently occurs in malpractice litigation and that arguably frustrates the rational use of guidelines in malpractice litigation. Research on medical malpractice litigation and medical injury suggests that a large reservoir of potential cases is not being brought on behalf of patients injured by negligence [4]. Part of the reason for this must be the difficulty and expense associated with recognizing and proving negligence. The availability of practice guidelines may lower these information barriers and costs, and hence the threshold for what would now be considered suits with merit. The same research shows that numerous cases are filed without merit, and use of guidelines can presumably reduce the quantity of these or lead to their being dropped at an early point. The two-way use of guidelines, as both inculpatory and exculpatory evidence, should in turn induce high rates of compliance with guidelines [23, 24].

Unfortunately, our results diminish the hope that guidelines will effectively eliminate the battle of the experts in malpractice litigation [9]. Few attorneys report that guidelines decrease the need for experts; in fact, slightly more report that guidelines increase this need. Hence, administrative costs per case may increase, although this increase would be counterbalanced by savings from claims not brought or settled early.

We should note several caveats of our study. First, we approached only two insurer companies. Most of the malpractice liability industry consists of physician insurers or hospital insurers; we chose one of each. It is notoriously difficult to get insurer permission to study open and closed claims, and so important research in this field is often limited to one insurer [25]. Our two companies are representative of the industry generally, but it would have been preferable to study more companies. The same caveat applies to our attorney survey: Because we had little information on nonrespondents, our sample was not necessarily representative. However, to the best of our knowledge, this is the largest survey of malpractice attorneys ever done.

We also may have underestimated the present use of guidelines in litigation by choosing claims from the late 1980s, which may have concerned care given in the mid-1980s and to which many newly formulated guidelines may not be applicable. Finally, we did not estimate the proportion of cases brought in which a guideline may have been applicable but was not used. Because more than 1400 guidelines are now available, we did not believe that this approach was possible given our research design.

Health care reformers, physicians, and guideline developers should know that guidelines are a double-edged sword. As exculpatory evidence, they could reduce the number of claims or lead to claims being dropped at an early stage in the litigation. But, insofar as physicians inappropriately fail to comply with them, guidelines can provide sturdy inculpatory evidence of the standard of care, as more and more malpractice attorneys are learning. If guidelines are developed and applied appropriately, this is not necessarily bad. Widespread use of guidelines in malpractice should lead to greater compliance with guidelines in the long term. But proponents of guidelines should be aware that the inculpatory use of guidelines in litigation may chill physicians' interest in developing more specific and prescriptive guidelines. This aspect of the inculpatory use of guidelines has been largely ignored by state and federal reformers. Education about the two-way use of practice guidelines in litigation should be a priority.