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Global variations in preoperative practices concerning patients seeking primary bariatric and metabolic surgery (PACT Study): A survey of 634 bariatric healthcare professionals



Bariatric and Metabolic Surgery (BMS) is a popular weight loss intervention worldwide, yet few scientific studies have examined variations in preoperative practices globally. This study aimed to capture global variations in preoperative practices concerning patients planned for BMS.


A 41-item questionnaire-based survey was designed and the survey link was freely distributed on social and scientific media platforms, email groups and circulated through personal connections of authors. The survey included eight parts: basic information; criteria for BMS; preoperative nutritional screening; preoperative weight loss; preoperative diets for liver size reduction; preoperative glycemic control; other laboratory investigations and preparations; decision making, education, and consents. Descriptive statistics were used to analyse data and graphs were used for representation where applicable.


Six hundred thirty-four bariatric healthcare professionals from 76 countries/regions completed the survey. Of these, n = 310 (48.9%) were from public hospitals, n = 466 (73.5%) were surgeons, and the rest were multidisciplinary professionals. More than half of respondents reported using local society/association guidelines in their practice (n = 310, 61.6%). The great majority of respondents routinely recommend nutritional screening preoperatively (n = 385, 77.5%), mandatory preoperative diets for liver size reduction (n = 220, 53.1%), routine screening for T2DM (n = 371, 90.7%), and mandate a glycemic control target before BMS in patients with T2DM (n = 203, 55.6%). However, less than half (n = 183, 43.9%) recommend mandatory preoperative weight loss to all patients. Most respondents (n = 296, 77.1%) recommend psychological intervention before surgery for patients diagnosed with psychological conditions. Variations were also identified in laboratory investigations and optimisation; and in the aspects of decision making, education and consent.


This survey identified significant global variations in preoperative practices concerning patients seeking primary BMS. Our findings could facilitate future research for the determination of best practice in these areas of variations, and consensus-building to guide clinical practice while we wait for that evidence to emerge.

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Fig. 1: Liver reducing diet (n = 341).
Fig. 2: Liver reducing diet duration (n = 341).
Fig. 3: Routine screening for T2DM (n = 365).
Fig. 4: Core members of MDT (n = 374).

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Data availability

The datasets generated during and/or analysed during the current study are available from the corresponding author on reasonable request.


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Authors and Affiliations



WY and KM conceived and designed the idea, wrote, and drafted the manuscript. WY, YG, and KM led the data analysis, interpretation, and manuscript preparation with input from all authors. All authors contributed to the survey design, survey distribution, data collection, editing, and revising the manuscript, and have read and approved the final manuscript.

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Correspondence to Wah Yang.

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Competing interests

MOK has been paid honoraria by Novo Nordisk for services provided/consultancy and Johnson and Johnson for educational activities. AT reports grants from Novo Nordisk, personal fees from Novo Nordisk, non-financial support from Novo Nordisk, personal fees from Eli Lilly, non-financial support from Eli Lilly, personal fees from Janssen, personal fees from AZ, non-financial support from AZ, non-financial support from Impeto medical, non-financial support from Resmed, non-financial support from Aptiva, personal fees from BI, non-financial support from BI, personal fees from BMS, non-financial support from BMS, personal fees from NAPP, non-financial support from NAPP, personal fees from MSD, non-financial support from MSD, personal fees from Nestle, personal fees from Gilead, grants from Sanofi, and personal fees from Sanofi outside the submitted work. AAT is currently an employee of Novo Nordisk. This work was performed before AAT became a Novo Nordisk employee and Novo Nordisk had no role in this project. KM has been paid honoraria by Ethicon, Medtronic, Gore, Olympus, and various NHS trusts for educational activities and mentoring colleagues through One Anastomosis Gastric Bypass. The other authors declare that they have no conflicts of interest.

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Yang, W., Abbott, S., Borg, CM. et al. Global variations in preoperative practices concerning patients seeking primary bariatric and metabolic surgery (PACT Study): A survey of 634 bariatric healthcare professionals. Int J Obes 46, 1341–1350 (2022).

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