Study Procedures
WEST
The study used a 2-group RCT design. Patients were screened by the research coordinator (S.E.L.) to determine their study eligibility. Patients self-reported race and ethnicity in a single question during the baseline questionnaire. Options were Aboriginal (eg, Inuit, Metis, or North American Indian), Arab or West Asian (eg, Armenian, Egyptian, Iranian, or Lebanese), Black (eg, African, Haitian, Jamaican, or Somali), East Asian (eg, Chinese, Japanese, or Korean), Latin American, South Asian, Southeast Asian, White, or other (patients typed in their own responses). Race and ethnicity were assessed given that most bariatric surgery programs have predominantly White populations (approximately 80%). We would possibly like to assess in a subanalysis whether race and ethnicity may be a predictor of treatment response for our intervention. This would also help to identify if there are any gaps in our intervention to inform future studies on better ways to adapt the intervention for more marginalized racial and ethnic groups. Participants completed a series of questionnaires at baseline (1 year after surgery; time 1 [T1]) and were subsequently randomized 1:1 to the tele-CBT or treatment-as-usual control group. Open randomization was used, with permuted blocks of sizes 4 and 6 and stratification by site. The randomization sequence was generated in R statistical software version 3.4.3 (R Project for Statistical Computing) and implemented initially through a custom web-based application, then switched to a manual reveal of allocations for the final few months of participant randomization given that the application was no longer supported. This was an unblinded study. Participants randomized to the control group received standard bariatric care, which included access to and ongoing monitoring by their multidisciplinary bariatric surgery team, including a dietitian, social worker, and psychologist, psychiatrist, or both. Participants randomized to the tele-CBT group received the intervention described subsequently. All participants completed the same questionnaires online using Qualtrics survey software version February 2018 to December 2021 (Qualtrics) after the intervention (approximately 15 months after surgery; time 2 [T2]) and at 3-month follow-up (approximately 18 months after surgery; hereafter, 