Obesity Surgery

, Volume 25, Issue 12, pp 2451–2456 | Cite as

Validation of the NASA-TLX Score in Ongoing Assessment of Mental Workload During a Laparoscopic Learning Curve in Bariatric Surgery

  • Juan Francisco Ruiz-Rabelo
  • Elena Navarro-Rodriguez
  • Leandro Luigi Di-Stasi
  • Nelida Diaz-Jimenez
  • Juan Cabrera-Bermon
  • Carlos Diaz-Iglesias
  • Manuel Gomez-Alvarez
  • Javier Briceño-Delgado
New Concept



Fatigue and mental workload are directly associated with high-complexity tasks. In general, difficult tasks produce a higher mental workload, leaving little opportunity to deal with new/unexpected events and increasing the likelihood of performance errors. The laparoscopic Roux-en-Y gastric bypass (LRYGB) learning curve is considered to be one of the most difficult to complete in laparoscopic surgery. We wished to validate the National Aeronautics and Space Administration Task Load Index (NASA-TLX) in LRYGB and identify factors that could provoke a higher mental workload for surgeons during the learning curve.


A single surgeon was enrolled to undertake 70 consecutive LRYGB procedures with two internal surgeons mentoring the first 35 cases. Patients were consecutive and ranked from case 35 to case 105 according to the date of the surgical procedure (“case rank”). Self-ratings of satisfaction, performance, and fatigue were measured at the end of surgery using a validated NASA-TLX questionnaire. The procedure was recorded for later viewing by two external evaluators. General data for patients and surgical variables were collected prospectively.


A moderate correlation between the NASA-TLX score, BMI, operative time, and volumes of blood drainage was observed. There was no correlation between the NASA-TLX score and duration of hospital stay or time of drain removal. BMI ≥50 kg/m2, male sex, inexperienced first assistant, and type 2 diabetes mellitus were identified as independent predictive factors of a higher NASA-TLX score.


The NASA-TLX is a valid tool to gauge mental workload in LRYGB.


Learning curve Laparoscopic Roux-en-Y gastric bypass Mental workload Bariatric surgery NASA-TLX 


Compliance with Ethical Standards

Conflict of Interest

The authors declare that they have no competing interests.

Statement of Informed Consent

Informed consent was obtained from all individuals participants included in the study

Statement of Human and Animal Rights

All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards

Grant Information

The study was supported by grant from the Fundación Progreso y Salud, Consejería de Bienestar y Politicas Sociales, Junta de Andalucía (PI-0340-2013)


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Copyright information

© Springer Science+Business Media New York 2015

Authors and Affiliations

  • Juan Francisco Ruiz-Rabelo
    • 1
  • Elena Navarro-Rodriguez
    • 1
  • Leandro Luigi Di-Stasi
    • 2
  • Nelida Diaz-Jimenez
    • 1
  • Juan Cabrera-Bermon
    • 1
  • Carlos Diaz-Iglesias
    • 1
  • Manuel Gomez-Alvarez
    • 1
  • Javier Briceño-Delgado
    • 1
  1. 1.General and Digestive Surgery DepartmentUniversity Hospital Reina SofiaCórdobaSpain
  2. 2.Cognitive Ergonomics Group, Mind, Brain, and Behavior Research Center (CIMCYC)University of GranadaGranadaSpain

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