Predictors of Bariatric Surgery Weight Loss

A validated SCOFF questionnaire will be self-administered to patients attending their first preoperative bariatric surgery appointment. The SCOFF questionnaire is a simple 5-question test developed to assess the possible presence of an eating disorder. The S in SCOFF stands for "sick" (to vomit). The O stands for "one stone" of weight (i.e., 6.35 kg). The letters C, F and F stand for "control", "fat" and "food" respectively. Although the SCOFF is not used for diagnostic purposes, a score of 2 or more positive answers raises the index of suspicion of eating disorders, highlighting the need for a more detailed psychological history .The SCOFF has been previously validated in Arab populations.

Kuwait University Anxiety Scale (KUAS)

The Kuwait University Anxiety Scale will be used to measure level of anxiety. The 20-item scale will capture cognitive/affective anxiety (9 items), subjective anxiety or nervousness (7 items), and somatic anxiety (4 items) [4]. Responses use a 4-point Likert scale ranging from 1=rare, 2=sometimes, 3= often, 4= always to measure the level of anxiety . The cut offs to indicate anxiety include 0 - 21 normal, 22 - 42 mild anxiety, 42 - 63 moderate anxiety, 64 - 84 severe anxiety.

Beck Inventory

Psychological screening and assessment for anxiety and depression will be carried by a clinical psychologist using a validated questionnaire. The Beck Depression inventory which includes a 21-item multiple choice self-report inventory will be used to measure depressive symptoms within the last week. Each question includes a set of 4 possible choices of how a participant may feel. Choices are scored from 0 to 3, increasing in intensity. The cut-offs to indicate depression include 0 - 9 minimal depression, 10 - 18 mild depression, 19 - 29 moderate depression, 30 - 63 severe depression.

Height and weight will be measured using standard protocols by a qualified nurse during the patient's preoperative and post-operative appointments. Body Mass Index (BMI) will be calculated using WHO cut-off points to define obesity. Obese patients will be divided into different classes of obesity as the following: obese class I (BMI 30 - 34.9 kg/m2), obese class II (35 - 39.9 kg/m2) and obese class III (BMI > 40 kg/m2).