The accomplishments of an individual surgeon and department chair may be quantified in myriad ways. Impact can be measured by the number of operations performed, by scientific discoveries, by the leadership positions held, the environment created by the faculty hired, by the institution and its resources, and notably by those who have been trained and influenced by this surgeon. As the operative career of John L. Cameron comes to a close this perspective focuses on a single sphere of his storied career: his influence on the training of academic surgeons during his time as the William Stewart Halsted Chair and Chief of Surgery at the Johns Hopkins Hospital in Baltimore, Maryland from the years 1984 to 2003. Dr Cameron's long-lasting and trans-generational impact on the fields of general and hepatopancreaticobiliary surgery has been described in both the academic and lay presses;1 indeed, former trainees have gone on to hold some of the highest positions within medical institutions and societies, across the range of subspecialties.
As is well known, Dr William Stewart Halsted was the first chief of surgery at the Johns Hopkins Hospital. While his innovative and influential accomplishments are well documented in medical science, perhaps his two most important accomplishments were the introduction of the philosophy of safe surgery and the initial system for training surgical residents.2,3 Halsted's biographers took care to enumerate his scientific and technological contributions, but they also suggested that his broader impact was evidenced by the fact that those “who went out from his operating room were magnificently trained, and are among the great ornaments of American surgery.” 2,3 We believe John Cameron has had a similar impact through the 106 individuals he has directly trained. This impact extends to those trained, in turn, by his trainees who have held positions as chairs or program directors. Borrowing from a theory of “collaborative distance” between investigators, that is, the degree to which they are related as coauthors, we propose the term “the Cameron Legacy Factor” as one metric of his influence. A measure of collaborative distance is useful for two reasons: (1) it describes the sheer number of individuals who were influenced directly by the individual, and (2) it also describes the depth and breadth of influence across fields and generations. The most famous of these include the Erdös number, which is named for the highly prolific mathematician Paul Erdös.4 Mathematicians who coauthored a manuscript with Paul Erdös are said to have an Erdös number of 1, those who authored papers with the coauthors, are said to have an Erdös number of 2, and so forth. Thus, the 106 individuals who trained under the chairmanship of John L. Cameron are said to have a Cameron Factor of 1. Individuals who completed residency or fellowship training under a chair, institute director, or program director with a Cameron Factor of 1 are considered to have a Cameron Factor of 2.
Of these 106 trainees, 84.0% (n = 89) pursued academic careers and 25.5% (n = 27) pursued careers in a private hospital or practice. Seventeen percent (n = 18) had careers that spanned both sectors simultaneously. Of those who pursued academic tracks as of 2015, 52.8% (n = 47) achieved the rank of full professor, 71.9% (n = 64) achieved the rank of associate professor, and 20.2% (n = 18) achieved the rank of institute director or chair. Of the individuals whose careers included a private institution, 37% (n = 10) were appointed chiefs of divisions, and 55.6% (n = 15) were appointed to positions that included departmental chairs or leadership boards. All surgical subspecialties were represented in the cohort, with the most common subspecialty being cardiothoracic surgery, which comprised 35.9% (n = 38) of all individuals; the next most common subspecialty was surgical oncology, practiced by 17.0%,(n = 18), followed by hepatopancreaticoobiliary surgery (6.6%, n = 7).
Over the course of 16 years, 20 individuals served as program directors, division chiefs, or departmental chairs who oversaw the training of residents and/or fellows. These individuals directed the training of an average class size of 6.1 residents or 2 clinical fellows per year. The total number of these individuals, who then are considered to have a Cameron Factor of 2, was estimated to be between 1150 and 1313 (Table 1). Insufficient time has elapsed to consider those with a Cameron Factor of 3.
Among individuals with a Cameron Factor of 1 who had an academic career, a total of 66 different institutions are represented, as are 9 different private hospitals or health systems, in over 33 different US states (Fig. 1). Also of note, 3 individuals served as founding directors of departments or divisions, and 7 achieved leadership roles that extended beyond chair, such as chief medical officer for a practice group, member of a leadership board, or deanship of a medical school.
Leadership can be defined in innumerable ways, but perhaps it can be best described by the process by which a person influences others to accomplish an objective and directs an organization (or department) in a way that makes it more cohesive and coherent. There is no doubt about the personal accomplishments of John L. Cameron as a surgeon, administrator, clinical researcher, and prolific scholar. His vision about the characteristics necessary for the development of a clinically and academically successful surgeon led to the selection and development of many of the divisional and departmental surgical leaders today. The trainees under the chairmanship of John L. Cameron document the substantial personal influence he has had on the development of surgical leaders both within and outside of academic institutions today. Irrespective of the individual interests and specialties of his graduates who have remained in academia, the majority have achieved promotion to the rank of full professor, and more than 20% have gone onto leadership positions as department chair, institute director, health system leader, or dean. In his Presidential address to the Southwestern Surgical Congress, Claude Organ performed an analysis of surgical leadership in the period from 1945 to 19855 identifying residency programs whose alumni produced the greatest number of surgical leaders. In doing so, he took care to point out that though certain institutions can attract and are able to develop talent by having both dedicated faculty and extensive resources, the influence of institutional leadership was paramount. Indeed, departmental and program leadership are uniquely situated to select and develop a talented resident cohort and to influence their subsequent positions as academic leaders.
How did the graduates of John Cameron achieve their success? Dr Cameron routinely personally provided advice and mentorship, and created an environment where his highly talented faculty did the same. He ensured that a research plan was well suited to each individual resident's academic development, even when it included nontraditional modes of study. For selected residents he encouraged further training in public health, management, or basic science. Although formal leadership programs were not dominant during this time period, many of these degree programs contained elements of leadership training.
We have proposed the term “Cameron Factor” to quantify the sheer magnitude of his impact on the world of surgery exclusively through his impact on those he directly trained, and specifically to honor his contributions to the training of subsequent generations. This legacy includes those residents with a Cameron factor of “1” (106) and those with a Cameron factor of “2” (1150–1313). Given the relatively short time frame of follow-up in this perspective, the full impact of those with a Cameron factor of 3 is unknown, but is likely to include another exponential increase in influence.
This perspective has not specifically outlined the numerous additional contributions of the Cameron trained residents such as those who have served as journal editors, society presidents, and leaders of major surgical institutions. In addition to the trainees described herein, 137 additional trainees have trained with Dr Cameron before or after his chairmanship. Further, he has also influenced the many faculty he worked with as colleagues, expanding the total number of full-time faculty by an estimated factor of three during his time as chair. Many of these trainees and faculty have also benefited from his mentorship and have gone onto leadership positions outside Johns Hopkins. Finally, this perspective has only considered the trainees and their accomplishments and not the actual accomplishments of Dr Cameron himself. We urge programs to consider their own “Cameron factors” as a tribute to this legacy. When we pause to consider how this influence may fit into the broader history of surgery worldwide, we are reminded of the comments made nearly 100 years ago by Sir Berkeley Moynihan about Theodor Kocher.6 “The chief legacy which a surgeon can bequeath is a gift of spirit. To inspire many successors with a firm belief in the high destiny of our calling, and with a confident and unwavering intention both to search out the secret of medicine in her innermost recesses, and to practice the knowledge so acquired with lofty purpose, high ideals and generous heart for the benefit of humanity – that is the best that a man can transmit.”6 While borrowed, these words could apply to John L. Cameron today.
The authors thank the Halsted Residents for providing their curricula vitae and James Griffin, MD, and Emmanouil Pappou, MD PhD for their efforts at data collection.