Cognitive Bias and Decision Making in Bariatric Surgery; Surgeons Preference for Sleeve or Band Depresses Performance on Questions Related to Esophageal

R Rutledge, MD

Center for Laparoscopic Obesity Surgery

We performed a survey of 112 international experts in bariatric surgery from 23 countries.
Surgeons were classified into; surgeons who preferred Band or the Sleeve (Pro-BS Surgeons) and surgeons who preferred the Mini-Gastric Bypass (Pro-MB).
Results: In summary Pro-MB Surgeons performed significantly better on all questions than Pro-BS Surgeons! Some examples are provided below:
"There are many large scale studies that show no increased risk of gastric cancer after Billroth II" i.e.: 30 yr f/u, over 500 pts., "Risk of gastric cancer is * Not * increased after partial gastrectomy." Bassily R, .J Gastro-Hepatology. 2000. 44% of Pro-BS Surgeons did NOT agree with this statement and 12% of Pro-MB surgeons disagreed.

"In a study from the Netherlands of 58,279 patients 162 stomach cancers were detected. A higher risk for stomach cancer was found for men with the lowest level of education (RR lowest/highest level = 2.0, p = 0.02) i.e. Lower education = higher risk of stomach cancer. Do you think less education "CAUSES" stomach cancer? Surprisingly 15% of Pro-BS surgeons answered: Less Education "Causes" Gastric Cancer!

"Unoperated Gastric Ulcer patients have double the risk for Gastric Cancer: Am J Gastroenterology 2007 Jun;102(6):1185-91. Pub 2007 Apr 13. Long-term risk of gastric cancer by subsite in operated and unoperated patients hospitalized for peptic ulcer. Bahmanyar S, et al. 29% Disagreed with this question, even though the relevant article was quoted and referenced for them.

"The death rate stomach cancer in the United States has dropped from 28 to 5 per 100,000 people." 25.4% of Pro_BS disagreed with this true statement.

"Numerous Studies Now Show that the Band and the Sleeve can increase acid reflux and be associated with Barretts & Esophageal Caner." While 64.5% of Pro-BS surgeons agreed with this statement 35.5%, over 1/3 disagreed. This in spite of 90% agreement with "GERD Increases Risk of Cancer of Esophagus" and "Treating or Avoiding GERD may protect & prevent Barrett’s & Esophageal cancer."

Pro-BS surgeons scored uniformly lower than Pro-MB surgeons

Overall it seems probable that Pro-BS surgeons are not less intelligent than Pro-MB surgeons. If that is so how can we explain the significantly higher error rate among the Pro-BS surgeons on questions of fact.

Many of our questions were referencing studies that tended to show the MGB in a positive light. Cognitive biases such as Reactance (the urge to do the opposite of what someone wants you to do out of a need to resist a perceived attempt to constrain freedom) may have led Pro-BS surgeons to answering questions incorrectly.

Conclusions: Studies clearly show a relation between surgeon’s knowledge performance and patient outcomes. This study demonstrated that surgeons who prefer the Sleeve and Band commonly make erroneous judgments about bile reflux, acid reflux, esophageal & gastric cancer and other important issues. If we hypothesize that this documented error rate is because of various cognitive biases then we may also have a means of improving these surgeon’s knowledge and performance.

Session: Poster Presentation

Program Number: P601