Table 2.

Individual factors contributing to bariatric surgery referral and receipt (adopted from Andersen’s Behavioral Model of Health Services Use)

Type of factor	Description	Barriers/facilitators and relevant citations
Predisposing
Demographic	Patient demographic characteristics and characteristics that affect the likelihood a person will need health services	Barrier: older age [41] Facilitator: younger age [39], female sex [27,39,41], white race [27]
Social	Measures of a persons’ status in the community and/or ability to cope with problems and use resources	Barrier: socioeconomic deprivation [39], rural residence [29], higher education level [44], professional occupation employment [40] Facilitator: urban residence [27], community social support [39], family influence [43]
Beliefs	Patient attitudes, values, and knowledge about health and health services (i.e., severe obesity, bariatric care) that can subsequently influence their perception of need and use of a health service	Barrier: fear of surgery [44] and postoperative complications [41,44,45], perception of surgery as “extreme” [45], concerns regarding postoperative restrictions [45], weight regain [41], and lack of control over amount of weight loss [41]
Enabling
Financing	Wealth available to a patient for health services, including the effective price of healthcare as determined by insurance status	Barrier: cost of bariatric surgery [40,41,45], patient uninsured status [40,43]
Organization	Encompasses whether a person has a regular source of care, location/type of care, their geographic distance from facilities, means of transportation, and wait times for consultations, referrals, etc.	Barrier: longer travel time to bariatric care facilities [47], unable to participate in preoperative program as indicated by missed appointments [41], lack of child care support for clinic appointments [41], physically incapable of commute [41], lack of choice regarding hospital, operation type, or surgeon for treatment [41]
Need
Perceived	Refers to how patients view their state of health (e.g., BMI, comorbidities), how much it causes them to worry, and how often they experience symptoms/ill-effects. This perception contributes to patient motivation to seek care or not	Barrier: not perceiving self as having severe obesity [13,40], unaware of bariatric surgery treatment [40], perception that bariatric surgery is a last resort [41,44] Facilitator: perceiving self as obese [45], worsening health status [43], low energy levels limiting activity [43], knowing someone who had successful bariatric surgery [43], higher BMI [41,44], higher number of co-morbidities [41,44]
Evaluated	Represents the necessity/indication for medical care/an intervention; dependent on objective measurement of a patients’ health and professional judgment based on clinical standards	Barrier: appropriateness for referral misevaluated due to inconsistent PCP adherence to evidence-based guidelines [20], PCP unfamiliarity with bariatric surgery indications and guidelines [15,18,21,22]
Health behaviors
Personal health practices	Patient practices that can affect health status	Barrier: inability to complete preoperative program after referral due to tobacco and marijuana use [41], preference for supervised diets as treatment [44] Facilitator: physical activity participation [39]
Process of medical care	Characterized as the behavior of physicians interacting with patients during the delivery of care, or interactions between physicians	Barrier: PCP deferring to patient to set treatment agenda [17] or initiate referral [19,20,40,45], inexperience providing bariatric referrals [20], discomfort counseling on obesity management [21] and explaining bariatric surgery procedures [22], fear of offending patients [15], perception that patients will be uninterested in discussing bariatric surgery [15], lack of communication training for obesity discussion [15]

BMI = body mass index; PCP = primary care physician.