Obesity Surgery

, Volume 30, Issue 2, pp 640–656 | Cite as

Learning Curves of Laparoscopic Roux-en-Y Gastric Bypass and Sleeve Gastrectomy in Bariatric Surgery: a Systematic Review and Introduction of a Standardization

  • F. S. Wehrtmann
  • J. R. de la Garza
  • K. F. Kowalewski
  • M. W. Schmidt
  • K. Müller
  • C. Tapking
  • P. Probst
  • M. K. Diener
  • L. Fischer
  • B. P. Müller-Stich
  • F. NickelEmail author
Original Contributions



The most commonly performed bariatric procedures are laparoscopic Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (LSG). Impact of learning curves on operative outcome has been well shown, but the necessary learning curves have not been clearly defined. This study provides a systematic review of the literature and proposes a standardization of phases of learning curves for RYGB and LSG.


A systematic literature search was performed using PubMed, Web of Science, and CENTRAL databases. All studies specifying a number or range of approaches to characterize the learning curve for RYGB and LSG were selected.


A total of 28 publications related to learning curves for 27,770 performed bariatric surgeries were included. Parameters used to determine the learning curve were operative time, complications, conversions, length of stay, and blood loss. Learning curve range was 30–500 (RYGB) and 30–200 operations (LSG) according to different definitions and respective phases of learning curves. Learning phases described the number of procedures necessary to achieve predefined skill levels, such as competency, proficiency, and mastery.


Definitions of learning curves for bariatric surgery are heterogeneous. Introduction of the three skill phases competency, proficiency, and mastery is proposed to provide a standardized definition using multiple outcome variables to enable better comparison in the future. These levels are reached after 30–70, 70–150, and up to 500 RYGB, and after 30–50, 60–100, and 100–200 LSG. Training curricula, previous laparoscopic experience, and high procedure volume are hallmarks for successful outcomes during the learning curve.


Learning curve Obesity surgery Laparoscopy Roux-en-Y gastric bypass Sleeve gastrectomy Competency Proficiency Mastery 



American Society for Metabolic & Bariatric Surgery


Body mass index


Cumulative sum analysis


Laparoscopic sleeve gastrectomy


Laparoscopic Roux-en-Y gastric bypass


International Federation for the Surgery of Obesity and Metabolic Disorders


Length of hospital stay


Newcastle-Ottawa Scale



We would like to thank Carly Rae Garrow for the linguistic revision of the manuscript.

Sources of Funding

The current study was supported by Stiftung Oskar-Helene-Heim ( in form of the Oskar Medizin-Preis that was awarded to F.N.

Compliance with Ethical Standards

Conflict of Interest

The authors declare that they have no conflict of interests.

Ethical Approval and Informed Consent

For this type of study, formal consent and ethical approval is not required.


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Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  • F. S. Wehrtmann
    • 1
  • J. R. de la Garza
    • 1
  • K. F. Kowalewski
    • 1
  • M. W. Schmidt
    • 1
  • K. Müller
    • 1
  • C. Tapking
    • 1
  • P. Probst
    • 2
  • M. K. Diener
    • 2
  • L. Fischer
    • 3
  • B. P. Müller-Stich
    • 1
  • F. Nickel
    • 1
    Email author
  1. 1.Department of General, Visceral, and Transplantation SurgeryUniversity of HeidelbergHeidelbergGermany
  2. 2.The Study Center of the German Surgical Society (SDGC)HeidelbergGermany
  3. 3.Department of SurgeryBaden-BadenGermany

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