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. 2022 Nov;92(11):3022-3028.
doi: 10.1111/ans.17830. Epub 2022 Jun 8.

The National Aeronautics and Space Administration-task load index: NASA-TLX: evaluation of its use in surgery

Stephen W Bell  1   2 , Joseph C H Kong  1   2 , David A Clark  3 , Peter Carne  1   2   4 , Stewart Skinner  1   2   4   5   6 , Stephen Pillinger  7 , Paul Burton  1   2   8 , Wendy Brown  1   2   8
Affiliations

The National Aeronautics and Space Administration-task load index: NASA-TLX: evaluation of its use in surgery

Stephen W Bell et al. ANZ J Surg. 2022 Nov.

Abstract

Background: The technical difficulty an operation creates for a surgeon is difficult to measure. Current measures are poor surrogates. In both research and teaching settings it would be valuable to be able to accurately measure this degree of difficulty. The National Aeronautics and Space Administration Task Load Index (NASA TLX) is a multi-dimensional scale designed to obtain workload estimates relating to a task. This study aimed to evaluate the NASA TLX as an objective measure of technical difficulty of an operation.

Methods: Seven surgeons performed 127 pre-defined operations (minimally invasive right hemicolectomy & re-do bariatric surgery) and recorded a NASA TLX score after each operation. These scores were compared to numerous clinical parameters and the score was correlated with the subjective measure of whether the surgeon categorized the operation as "easy", "moderate" or "difficult".

Results: The NASA TLX score was significantly correlated with operative duration, blood loss, previous abdominal surgery and the surgeons' assessment of difficulty. It did not correlate with intra-operative or post-operative complications, conversion to open surgery or length of stay.

Conclusions: The NASA TLX score provides a graded numerical score that that correlated significantly with the surgeon's assessment of the technical difficulty, and with operative duration, intra-operative blood loss and previous abdominal surgery. This novel application of this tool could be employed in both research and teaching settings to score surgical difficulty and monitor a trainee's proficiency over time.

Keywords: NASA TLX; bariatric surgery; surgical research.

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Conflict of interest statement

None declared.

Figures

Fig. 1
Fig. 1
NASA‐TLX score versus surgeon's assessment, operative time, blood loss & previous surgery. NASA‐TLX: National Aeronautics and Space Administration Task Load Index. Surgeon's assessment: 1 = Easy. 2 = Moderate, 3 = Difficult; Previous surgery: 0 = no previous surgery, 1 = prior surgery.
Fig. 2
Fig. 2
NASA TLX score vs. length of stay, intra‐ and post‐operative complications. NASA‐TLX: National Aeronautics and Space Administration Task Load Index. Complications: 0 = no; 1 = yes.
Fig. 3
Fig. 3
Individual NASA TLX scores generated by each surgeon median and IQR (whisker plot) and 95% confidence interval (box plot). NASA‐TLX: National Aeronautics and Space Administration Task Load Index.
See this image and copyright information in PMC

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