title: Productivity change of surgeons in an academic year.
abstract: OBJECTIVE
  The goal of this study was to calculate total factor productivity of surgeons in an academic year and to evaluate the effect of surgical trainees on their productivity.
  
  
  METHODS
  We analyzed all the surgical procedures performed from April 1 through September 30, 2013 in the Teikyo University Hospital. The nonradial and nonoriented Malmquist model under the variable returns-to-scale assumptions was employed. A decision-making unit is defined as a surgeon with the highest academic rank in the surgery. Inputs were defined as the number of physicians who assisted in surgery, and the time of surgical operation from skin incision to skin closure. The output was defined as the surgical fee for each surgery. April is the beginning month of a new academic year in Japan, and we divided the study period into April to June and July to September 2013. We computed each surgeon's Malmquist index, efficiency change, and technical change.
  
  
  RESULTS
  We analyzed 2789 surgical procedures that were performed by 105 surgeons. The Malmquist index of all surgeons was significantly greater than 1 (p = 0.0033). The technical change was significantly greater than 1 (p < 0.0001). However, the efficiency change was not statistically significantly different from 1 (p = 0.1817).
  
  
  CONCLUSIONS
  The surgeons are less productive in the beginning months of a new academic year. The main factor of this productivity loss is considered to be surgical training.
authors.affiliation: Teikyo University Graduate School of Public Health, Tokyo, Japan. Electronic address: ynakata@med.teikyo-u.ac.jp.
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Nakata
authors.affiliation: Teikyo University Graduate School of Public Health, Tokyo, Japan.
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Watanabe
authors.affiliation: Department of Anesthesia, Showa University School of Medicine, Tokyo, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Otake
authors.affiliation: Department of Health Policy for Aged Society, Chiba University Hospital, Chiba, Japan.
authors.forename: Toshihito
authors.initials: T
authors.lastname: Nakamura
authors.affiliation: Hamamatsu University School of Medicine, Hamamatsu, Japan.
authors.forename: Giichiro
authors.initials: G
authors.lastname: Oiso
authors.affiliation: Teikyo University Medical Information and System Research Center, Tokyo, Japan.
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Sawa
mesh_terms: D002983:Clinical Competence; D017598:Efficiency, Organizational; D013502:General Surgery / Q000193:education*; D006784:Hospitals, Teaching / Q000706:statistics & numerical data; D006801:Humans; D007396:Internship and Residency; D007564:Japan; D009873:Operating Rooms / Q000458:organization & administration*; D066231:Surgeons; D013514:Surgical Procedures, Operative / Q000706:statistics & numerical data*
keywords: Malmquist index; Patient Care; Practice-Based Learning and Improvement; Systems-Based Practice; efficiency change; surgical training; technical change