Our study documents the rate, nature, and consequences of all errors detected by attending hospitalist physicians caring for patients at a 200-bed academic hospital. All errors discovered by two hospitalists during routine clinical care of the patients were documented, and reports of errors from other health care providers were included. Using this method, 10.4% of all admissions were complicated by an error: 6.2% by a near miss and 4.2% by an adverse event. While the length of stay was greater in patients who experienced errors compared with patients who did not, this is not necessarily a result of the errors, but likely represents increased exposure to possible errors.
Lack of consensus regarding definitions of “error,”“adverse event,” and “near miss” makes direct comparisons of the rate of errors found in this study with those found in other studies difficult. The definition of “adverse event” used in this study differed somewhat from that used in the Harvard MPS. That definition included only events that prolonged hospital stay or caused disability at the time of discharge.2
Counting only errors that fit the MPS definition, an adverse event rate of 2.1% of all admissions was found in this study, slightly lower than the rate of 3.7% reported in the MPS. Similar to previous studies of errors among medical patients, drug errors were the most common type of error and near misses were more common than adverse events.3–6
Several important issues should be considered in the interpretation of this study. The study was conducted at only 1 site and by only 2 attending physicians, potentially limiting the generalizability of the results. The attendings had no formal training in error detection, but relied on the knowledge gained by review of the literature before commencing data collection.
There was no external review of the cases to verify the occurrence of errors, or to pick up on errors that may have escaped detection. The attendings also did not conduct chart reviews to investigate reports of errors by other team members and to detect errors that these team members may not have reported. Instead, they relied on information gathered during the course of routine clinical care. While these issues may have resulted in under-reporting of the total number of errors, the study was specifically designed to determine what practicing physicians could detect in the course of everyday clinical care.
The ability to detect errors is likely related to the amount of time spent on the wards and degree of involvement with daily patient care. The hospitalists in this study had limited presence on the wards during evenings and weekends, increasing the likelihood of missed errors during those times. Other, nonhospitalist attending physicians may have even less involvement with inpatient care. Despite concern over litigation that may result from reporting errors on their own patients, the hospitalists were highly motivated to detect errors, as they were the primary investigators for the study. Not all physicians are likely to be as motivated to detect and report errors, but this study demonstrates what can be accomplished.
Our study makes several contributions to the field of error reporting. First, the reliance on reporting by practicing physicians engaged in routine patient care, while potentially limiting detection, renders the errors that were detected highly clinically relevant. The study provides a perspective on the types and rates of errors that can be expected from self-reports if practicing attending physicians were to take an active role in monitoring health care quality.
Quality improvement initiatives are often criticized for being costly and difficult to implement. Faced with limited resources and rising costs, health care professionals are often reticent to embark on such initiatives. The method of error detection we used is practical and could be readily adopted in clinical settings with minimal associated expense.
A recent study9
suggests that agreement is moderate in judgments about adverse events among reviewers of medical records. This does not address the issue of accuracy of these judgments, however. Indeed, one study7
showed that errors reported by house staff physicians (who were prompted by e-mail) were detected by independent, retrospective medical record review in fewer than 50% of cases. Prospective error reporting will improve our understanding of the spectrum of errors encountered in clinical practice. This understanding can enhance patient safety in the future.
While other studies have employed house staff detection and reporting of errors, no other study to date has examined the differences in the types of errors reported by various health care providers caring for the same patients. Despite the fact that the near misses were far more common than the adverse events, house staff, nurses, and ancillary staff were somewhat more likely to detect the adverse events. Attending physicians were somewhat more likely than house staff to detect therapeutic errors. While these differences did not achieve statistical significance, it is not surprising that the detection and reporting of errors is not uniform among providers, given their distinct roles in patient care. These differences highlight the importance of having as many different types of health care providers involved in error reporting as possible.
Few large-scale studies of near misses have been conducted by the medical community. Other industries, such as the nuclear power industry or aviation industry, actively study near misses and their relation to adverse events.1
Near misses occur at a higher frequency than adverse events, thus facilitating their study. These other industries have capitalized on the fact that the same systems issues can be involved with both near misses and adverse events, with the only distinguishing feature being recovery mechanisms. Indeed, there were no substantial differences in the types of errors (e.g., drug, therapeutic, etc.) that made up the near misses compared to the adverse events. Lessons learned from near misses should be applied to prevent actual adverse events.
Fear of legal repercussions is a major barrier to more open reporting of mistakes by health professionals. While the IOM report calls for increased protection from litigation to encourage more open reporting of adverse events, this protection has not yet come to fruition. Study and report of near misses obviates this problem to some extent, because errors not associated with ill effects for the patient are less likely to be used as the basis for malpractice litigation. Increased study of near misses may prove to be an important part of expanding our current knowledge of errors. Armed with this improved understanding, it will then be possible to move forward in implementing and evaluating systems changes so that medical care is safer in the future.