Evolution of the Morbidity and Mortality Conference in Surgery: From Codman to Contemporary Practice

Abstract

The morbidity and mortality (M&M) conference is a foundational tradition in surgery, serving as a forum for education, accountability, and patient safety for more than a century. Originally rooted in early efforts to track outcomes and improve hospital efficiency, M&M has evolved alongside major developments in surgical education, quality improvement, and patient safety science. This review traces the historical evolution of the M&M conference from Ernest Codman’s end-result system to its institutionalization by the American College of Surgeons and formalization in graduate medical education. It examines the cultural shift from individual blame toward systems-based learning, highlights the influence of the patient safety movement, educational theory, and human factors science, and reviews contemporary approaches incorporating data analytics, multidisciplinary participation, and technology. Persistent challenges including variability in structure, underreporting, and medicolegal concerns along with future opportunities to strengthen M&M as a driver of continuous improvement are discussed. Despite ongoing evolution, the core purpose of honest reflection in service of safer and higher-quality surgical care in M&M remains unchanged.

Introduction

For generations, the surgical morbidity and mortality (M&M) conference has served as a structured forum for surgeons to review adverse outcomes, critically examine clinical decision-making, and reaffirm professional accountability. ¹ Despite dramatic advances in surgical technology, perioperative care, and health care delivery systems, M&M has remained a central pillar of surgical education and professional culture. ² At its core, the M&M conference reflects a commitment to transparency and self-examination. It provides an avenue to transform complications, near misses, and deaths into learning opportunities that improve future patient care. ¹ Historically, M&M has also served as a powerful venue for professional socialization. Through this closed-door forum within surgical departments, surgeons share case discussions to learn not only technical lessons but also how the profession conceptualizes error, uncertainty, responsibility, and professionalism. ³

Over time, alongside advancements in health care and surgical care, the purpose and culture of M&M have evolved. Early M&M conferences frequently focused on individual responsibility and technical judgment, often in ways that reinforced hierarchy and blame. As surgical care became increasingly complex, multidisciplinary, and system-dependent, this siloed approach did not align with evolving health care culture and proved insufficient. Growing recognition that adverse events often arise from system failures rather than isolated individual errors prompted a fundamental re-evaluation of how M&M conferences should function. ⁴

Historical Foundations of Morbidity and Mortality Review

Early Outcome Review and the Transformation of Hospitals

At the turn of the 20th century, hospitals in the United States were undergoing profound changes. No longer serving primarily as charitable institutions for the poor and dying, hospitals were becoming organized centers for patient care, medical education, and scientific inquiry. ⁵ This transition created the conditions necessary for a new systematic way to evaluate patient outcomes rather than relying on anecdote or individual recollection. ⁶ Initially, the review of mortality and complications emerged as part of broader efforts to improve hospital efficiency and professional accountability. Although informal and inconsistently applied, these discussions reflected a shift away from viewing adverse outcomes as associated with individual failure, instead reframing these events as an opportunity for analysis of care systems and broader organizational learning. This emerging focus on outcome measurement laid out the groundwork for later quality improvement efforts.^5,7

Ernest Codman and the End-Result System

The individual most closely associated with early outcome measurement in surgery was Ernest Amory Codman. Codman proposed that every patient should be followed until the final outcome was known. His “End-Result System” required rigorous documentation of diagnoses, treatments, complications, and outcomes, with the explicit goal of identifying opportunities for improvement and ideally achieving surgical perfection, which later evolved into the modern concept of quality improvement.^7,8 Codman’s insistence on transparency was revolutionary and controversial at that time. He argued that surgeons and hospitals should openly acknowledge failures and use them as the basis and opportunity for improvement, even at the risk of professional embarrassment. However, his peers strongly criticized his interest in public reporting to improve surgical care. These views placed him at odds with many of his contemporaries and led to his professional isolation. ⁹

Despite resistance during his lifetime, Codman’s philosophy anticipated and emphasized the core principles of what later became the modern quality improvement and patient safety movement. His emphasis on measurement, feedback, and accountability forms the ethical and conceptual foundation of the modern M&M conference, which remains central to its purpose today.^7,9

Institutionalization Through the American College of Surgeons

Codman’s ideas gained broader acceptance through institutional mechanisms with the founding of the American College of Surgeons (ACS) in 1913. Under the leadership of Franklin Martin, the ACS sought to standardize surgical practice and improve the quality of hospital care.^9,10

In 1918, the ACS launched the Hospital Standardization Program, which required accurate medical records and routine mortality review as conditions for hospital approval. ¹⁰ These requirements transformed outcome review from an individual reform effort into an organizational expectation and laid the structural foundation for formal M&M conferences within academic surgery. ¹⁰

Early M&M Conference Culture

By the late-20th century, M&M conferences were embedded in surgical training programs. Residents typically presented cases involving complications or deaths, and senior surgeons discussed and offered critique. ¹¹ These conferences reinforced technical excellence and decisional responsibility. Discussion emphasized individual judgment or technical execution while system contributors such as communication failures, workflow design, staffing, or resource limitations were frequently overlooked. The resulting culture was often hierarchical and punitive, discouraging open disclosure and limiting broader learning. ¹¹

Forces That Drove Change in the M&M Conference

Professional Culture and the Interpretation of Error: Charles Bosk

Early insight into why M&M conferences functioned as they did derived from sociological inquiry rather than empirical outcomes research. In a landmark study of surgical training, Charles Bosk examined how surgeons and trainees interpreted failure within the surgical professional culture. ¹² Bosk demonstrated that technical and judgment errors were often tolerated, particularly when openly acknowledged and framed as part of the learning process, while violations of professional norms such as dishonesty, lack of responsibility, or failure to disclose were far less forgivable. ¹² These findings revealed that responses to adverse outcomes were shaped not solely by clinical facts, but also by cultural norms of accountability, trust, and professionalism. Importantly, Bosk showed that punitive responses were selectively applied depending on the type of error, and that informal cultural rules often determined whether adverse events became learning opportunities or sources of stigma. This sociological perspective explains why traditional M&M conferences could simultaneously serve as powerful educational tools and as intimidating, blame-oriented forums, depending on how errors were framed, discussed, and perceived by the surgeons. ¹²

Learning Theory, Hierarchy, and Psychological Safety

Subsequent advances in educational theory provided a framework for understanding why these cultural dynamics mattered for learning. ¹³ Adult learning theory emphasizes reflection, relevance, and psychological safety as prerequisites for meaningful and durable improvement. Psychological safety refers to the ability to speak up, disclose uncertainty, and discuss errors without fear of humiliation or retribution and has been shown to facilitate error reporting, collective problem-solving, and adaptive learning, which are key components of patient safety.^5,14

In surgical environments historically defined by hierarchy and expectations of perfection, the absence of psychological safety can suppress disclosure and reinforce defensive behavior that may adversely affect patient outcomes.^12,15 From this perspective, the M&M conference functions not only as an educational exercise but as a visible test of institutional values. Adversarial or punitive formats, while emotionally salient, may undermine learning by discouraging honest reflection, whereas psychologically safe, structured discussions are more likely to support improvement. ¹⁵

Role of the Accreditation Council for Graduate Medical Education

By the 1980s, M&M conferences became increasingly formalized within graduate medical education and their educational value was widely recognized across surgical training programs. In 1983, the Accreditation Council for Graduate Medical Education (ACGME) mandated weekly M&M conferences as a requirement for residency accreditation, establishing M&M as a core educational activity and reinforcing its role in reflection, professionalism, and accountability within training programs. ¹⁶

Systems Thinking and the Influence of Lucian Leape

In the 1990s, the conceptual foundation of M&M review was fundamentally reshaped by the work of Lucian Leape. Challenging the prevailing assumption that adverse outcomes were primarily the result of individual negligence or incompetence, Leape argued that most errors arise from predictable failures in poorly designed systems. ¹⁷ These ideas gained broad national attention with the publication of the Institute of Medicine’s report To Err Is Human, ¹⁸ which framed medical error as a major public health problem and reinforced Leape’s argument that system design, rather than individual vigilance, is the primary determinant of patient safety. ¹⁹

This systems-oriented framework shifted attention from individual culpability to underlying process vulnerabilities, providing a critical bridge between traditional case-based review and modern patient safety science. ¹⁸ Rather than asking who was at fault, Leape’s work reframed the central question toward why an error occurred and how similar events could be prevented through redesign, standardization, and organizational learning. These ideas fundamentally transformed expectations for M&M conferences, reframing them as opportunities to identify system failures and develop prevention strategies that improve patient outcomes.

Operationalizing Safety: The Contribution of Atul Gawande

Building on the systems-oriented framework advanced by Leape and reinforced by the Institute of Medicine, Atul Gawande translated patient safety theory into practical interventions. ²⁰ Through narrative case analysis and empirical observation, Gawande illustrated how well-intentioned, competent clinicians operating within flawed systems can nonetheless produce preventable harm. His work emphasized that recognition of error alone is insufficient without mechanisms to promote reliable execution and prevent recurrence.

In Complications, ²⁰ Gawande explored how surgical outcomes are shaped by complexity, uncertainty, and imperfect human performance, reinforcing the need for structured approaches for error prevention. Later, in The Checklist Manifesto, ²¹ he showed that simple, standardized tools, when embedded within supportive team cultures, can meaningfully reduce morbidity and mortality within clinical settings. These contributions helped redefine safety not as an individual cognitive achievement but as a collective, system-based discipline.

For M&M conferences, Gawande’s work exposed a critical limitation of traditional culture and format, which was focused on insight without structured implementation. His emphasis on checklists, standardization, and teamwork underscored that identifying contributing factors during M&M discussions must be paired with concrete process changes to achieve sustained improvement. ¹¹ In this way, Gawande’s contributions serve as a practical extension of Leape’s system-based framework, emphasizing how lessons from adverse events can be translated reliably into safer routine practice.

Evidence That Proactive Systems Improve Outcomes

The movement toward system-based approaches to patient safety is now evident in everyday clinical practice across multiple institutions. Trauma systems, for example, which integrate regionalization, standardized protocols, and continuous quality improvement, have been associated with significant reductions in mortality across diverse settings. ²² These successes underscore a central lesson of modern safety science: durable gains in patient safety are most likely when well-designed systems support, rather than depend solely upon, individual vigilance. Accordingly, M&M conferences that are explicitly aligned with system-improvement efforts are more likely to yield meaningful and sustained benefits. ¹¹

Morbidity and Mortality Conference: Practice, Challenges, and the “Ideal”

Contemporary Practice

Modern M&M conferences increasingly employ structured formats, standardized case presentation templates, and explicit learning objectives. These structures are designed to shift discussion away from individual faultfinding and toward identification of contributing factors and actionable prevention strategies. ¹¹ Equally important is multidisciplinary participation. Inclusion of nursing, anesthesiology, quality specialists, and administrative leadership extends the focus beyond individual performance to a more comprehensive evaluation of the perioperative system. This team-based approach reflects the reality that contemporary surgical care is delivered by interdependent professionals rather than isolated individuals. ²³

Data, Technology, and Objective Case Identification

Advances in data infrastructure have transformed M&M conferences. Clinical registries, electronic health records, and analytic dashboards allow for objective case identification and benchmarking, reducing reliance on voluntary reporting and minimizing selection bias. ²⁴

Emerging applications of artificial intelligence may further improve the identification of high-risk cases, near misses, and latent safety threats. Despite their promise, these tools must be integrated carefully to augment clinical judgment and foster meaningful reflective discussion. ²⁵

Persistent Challenges and Ongoing Variability

Despite substantial progress, including decades of cultural change and the implementation of practical strategies to promote patient safety and system-based improvements, important gaps persist in the function of M&M conferences. Through the Clinical Learning Environment Review (CLER) program, the ACGME has highlighted that many residents continue to have limited exposure to institutional patient safety and quality improvement activities, including inconsistent involvement in adverse event analysis and follow-up efforts. ²⁶ These observations suggest that, in many settings, M&M conferences do not reliably serve as effective gateways to systems-based learning for trainees.

Studies conducted among ACS-affiliated surgeons and trainees demonstrate substantial variability in whether actionable items identified during M&M conferences are clearly defined, assigned ownership, and reassessed over time.^14,27 Operational and cultural barriers continue to impede the effectiveness of M&M conferences. Variability in conference structure across institutions leads to uneven educational and quality outcomes. Furthermore, time constraints, competing clinical responsibilities, and medicolegal concerns often restrict comprehensive case selection and discussion. ¹¹ Most critically, many conferences struggle to convert insights into sustained improvement. Action items are often generated but inconsistently tracked, and feedback mechanisms linking discussion to measurable change are often inadequate. Bridging the gap between case review and durable system-level change remains a central challenge in contemporary M&M practice.

Together, these findings underscore that while M&M conferences are nearly universal across surgical training programs, their effectiveness as learning tools and drivers of system-based improvement continues to evolve.

The Ideal Future State of the Morbidity and Mortality Conference

In its ideal future state, the M&M conference operates as an integrated component of a learning health system rather than a discrete educational exercise. Its purpose extends beyond retrospective case review, ensuring insights from adverse events are systematically translated into sustained system-level processes that enhance patient outcomes. A central feature of this model is objective, data-driven case identification rather than relying on voluntary reporting or discretionary selection, which risks under-recognition of complications and introduces selection bias. ¹¹ As demonstrated by Hutter and colleagues, ¹⁶ registry-based surveillance through the ACS National Surgical Quality Improvement Program (NSQIP) captures substantially more complications and deaths than traditional M&M reporting, including events occurring after hospital discharge. Incorporating standardized data sources into M&M workflows ensures more comprehensive and representative case review.

The rapid advancement and use of technology further supports this ideal state by enabling longitudinal tracking of outcomes and trends. Electronic health records, registries, and analytic dashboards can reveal patterns of harm that may be missed through isolated case review, while emerging automated detection tools have the potential to augment adverse event identification. ²⁵ Importantly, technology serves to support, not replace, clinical judgment and reflective discussion, which remain central to the process. While data enhance transparency and completeness, meaningful learning continues to depend on multidisciplinary interpretation and engagement.

Realizing the “ideal” future state requires structured follow-through. In high-functioning M&M conferences, actionable items are explicitly defined, assigned specific ownership, and reassessed over time, with feedback provided to participants. ¹¹ Without deliberate processes to close the loop, even high-quality discussion may fail to produce lasting change.

Psychological safety is a critical element of this model. Conferences should be structured to encourage open participation across disciplines and training levels, reinforcing that error disclosure is a pathway to improvement rather than blame. At the same time, accountability should be maintained through structured analysis of contributing factors and clearly defined expectations for follow-up and improvement.

Finally, the “ideal” M&M conference needs alignment with institutional quality and safety infrastructure. Integration with hospital quality programs, patient safety offices, and educational leadership ensures that lessons identified during case review inform broader improvement efforts. In this integrated model, M&M conferences function not only as educational forums but as visible engines of organizational learning and patient safety.

Conclusion

From Codman’s early work in patient outcome tracking to today’s structured, systems-oriented forums, the M&M conference has continually evolved toward learning and patient safety. Its form may have changed, but its central purpose remains unchanged: honest reflection to enhance patient care. Surgical departments and their leaders bear the responsibility of upholding rigor without blame, fostering accountability while maintaining psychological safety, and ensuring meaningful follow-through. In this way, M&M conferences fulfill both their educational mission and the ethical imperative to demonstrate how teams learn together to improve care for future patients.