Analysis of surgical errors in closed malpractice claims at 4 liability insurers Selwyn O. Rogers, Jr, MD, MPH, a,b Atul A. Gawande, MD, MPH, a,b Mary Kwaan, MD, a Ann Louise Puopolo, BSN, RN, c Catherine Yoon, MS, a Troyen A. Brennan, MD, JD, MPH, a,d and David M. Studdert, LLB, ScD, MPH, d Boston, Mass Background. The relative importance of the different factors that cause surgical error is unknown. Malpractice claim file analysis may help to identify leading causes of surgical error and identify opportunities for prevention. Methods. We retrospectively reviewed 444 closed malpractice claims, from 4 malpractice liability insurers, in which patients alleged a surgical error. Surgeon-reviewers examined the litigation file and medical record to determine whether an injury attributable to surgical error had occurred and, if so, what factors contributed. Detailed descriptive information concerning etiology and outcome was recorded. Results. Reviewers identified surgical errors that resulted in patient injury in 258 of the 444 (58%) claims. Sixty-five percent of these cases involved significant or major injury; 23% involved death. In most cases (75%), errors occurred in intraoperative care; 25% in preoperative care; 35% in postoperative care. Thirty-one percent of the cases had errors occurring during multiple phases of care; in 62%, more than 1 clinician played a contributory role. Systems factors contributed to error in 82% of cases. The leading system factors were inexperience/lack of technical competence (41%) and communication breakdown (24%). Cases with technical errors (54%) were more likely than those without technical errors to involve errors in multiple phases of care (36% vs 24%, P = .03), multiple personnel (83% vs 63%, P .001), lack of technical competence/knowledge (51% vs 29%, P .001) and patient-related factors (54% vs 33%, P = .001). Conclusions. Systems factors play a critical role in most surgical errors, including technical errors. Closed claims analysis can help to identify priority areas for intervening to reduce errors. (Surgery 2006;140:25-33.) From the Brigham and Women’s Hospital, a and Brigham and Women’s Hospital and Center for Surgery and Public Health b ; the Harvard Risk Management Foundation c ; and the Harvard School of Public Health d Reducing the incidence and cost of medical injuries has become a national health care priority in the United States. Estimates from previous pa- tient safety research suggest that one half to two thirds of inpatient adverse events are attributable to surgical care, 1-3 and that more than half of these events may be preventable. 3,4 However, prevention efforts depend on detailed knowledge of the etiol- ogy of errors in surgery, which remains meager. Researchers have linked poor surgical outcomes to a wide variety of factors, including surgeon in- experience, 5-7 low hospital volume for some oper- ations, 8-14 excessive workload, 15 fatigue, 16,17 lack of optimal technology, 18 poor supervision of train- ees, 19 inadequate hospital systems, 20 poor staff communication, 21 emergency circumstances, 22 and time of day. 23 Many of these are “systems” factors— that is, they involve interrelationships between in- dividuals, their tools, and the environment they work in, rather than single straightforward causes. However, determining the relative importance of these causal factors in surgical errors to target interventions has proved extremely difficult. Supported by grant HS011886-03 from the Agency for Health- care Research and Quality and the Harvard Risk Management Foundation. Dr Studdert also was supported by grant KO2HS11285 from the Agency for Healthcare Research and Quality. Accepted for publication January 20, 2006. Reprint requests: Dr Studdert, Harvard School of Public Health, 677 Huntington Ave, Boston, MA 02115. E-mail: studdert@ hsph.harvard.edu 0039-6060/$ - see front matter © 2006 Mosby, Inc. All rights reserved. doi:10.1016/j.surg.2006.01.008 SURGERY 25