Table 2.

Hypothetical clinical presentations with proposed recommendations.

Diagnosis	Hypothetical Patient Demographics	Hypothetical Clinical Presentations	Proposed Recommendations
Bulimia Nervosa  (Low WS)	Female; 28 y.o.; 5’4” Highest weight: 180 lbs Current weight: 174 lbs, BMI = 29.9 (overweight) Duration of illness: 3 months; purging 2× daily	WS = 6 This patient is currently at an obese BMI, where traditional health parameters would recommend weight loss. Being told by medical weight management staff that she was obese with fatty liver disease triggered the onset of her compensatory behaviours.	Consider BMI Category from a Patient Perspective: For this patient, her perception of her BMI classification is impacting her maintenance of ED symptoms. Her WS is low, but the result of this BMI class change holds value, and may complicate treatment (e.g., patient resistant to returning to her potentially genetically and biologically determined obese weight). For this patient, de-emphasizing BMI during treatment might be helpful.
Bulimia Nervosa  (High WS)	Male; 59 y.o.; 5’9” Highest weight: 280 lbs Current weight: 169 lbs, BMI = 25.0 (normal) Duration of illness: 42 years; over-exercise, muscle dysmorphia	WS = 111 This patient was bullied related to his weight as a teenager, which he reports triggered his eating disorder onset. Currently, he reports extreme fear of returning to his former size. He sought employment at a gym 4 years ago to facilitate his exercise behaviour and reports no other activities other than his full-day workouts. He was referred to treatment by his orthopedist, treating him for several injuries resulting from over-exercise.	Consider WS and ED within gender and cultural norms: Exercise is currently culturally sanctioned, but motivation for weight loss for some individuals can be problematic. For this individual, some WS may have improved his metabolic function, but his current behaviour that maintains his WS has led to loss of quality of life, and risk for Relative Energy Deficiency in Sport. Consider that treatment may involve some weight gain and changes in body composition as patient move towards adaptive exercise and eating patterns.
Binge Eating Disorder  (Low WS)	Male; 33 y.o.; 5’8” Highest weight: 250 lbs Current weight: 246 lbs, BMI = 38 (obese) Duration of illness: 6 years with history of extreme weight cycling; binge eating three times per week	WS = 4 This patient has minimal WS. However, he is at risk for complications related to his eating disorder, as well as metabolic and related disease given his weight status.	Consider current WS and history of WS in treatment: This patient demonstrates low current WS. However, if this patient has had extensive experience of weight cycling, he may be at a comparatively high lifetime weight currently. A treatment provider should consider weight history, as well as current presentation in guiding clinical recommendations within the context of intervention.
Binge Eating Disorder  (High WS)	Female; 48 y.o.; 5’4” Highest weight (pre-Roux-n-Y surgery): 299 lbs Current weight: 145 lbs, BMI = 24.9 (normal) Duration of illness: 4 months; binge eating once per week	WS = 154 This patient presents for treatment at her nadir for post-surgical weight loss. Her BMI is within the normal range, and her pre-surgical obesity related comorbidities (hyperlipidemia, Diabetes mellitus) have resolved. She gets consistent praise from family, friends, and her medical providers for the progress she has made in achieving her current weight. Patient is compliant with post-surgical dietary and lifestyle recommendations, other than when she engages in binge eating. She also reports life history of major depressive disorder, with recent psychosocial stressors.	Consider WS within specific populations: This patient is at risk for post-surgical complications resulting from her eating behaviour, with potential for substantial weight regain. Whilst her WS is high, there are other factors that may be more salient in impacting her eating behaviour, including her history of, and current experience of depression which should be clinically treated.
Anorexia Nervosa	Female; 41 y.o.; 5’6” Highest weight: 125 lbs Current weight: 110 lbs, BMI 17.8 (underweight) Duration of illness: 6 years; primary restriction	WS = 15 This patient had a low premorbid BMI (20.2), so reductions in her weight do not appear substantial. However, her current weight is significantly below a healthy range for her height. We might say that her WS is low, but her overall risk for maintenance of ED and related complications is high.	Establishing a cutoff below which a %BWL in the context of WS might increase risk: Patient has 12% body weight loss (BWL). Future research might establish a cutoff below which a WS as reflected by %BWL reflects higher risk, and predicts poorer outcome.
Atypical Anorexia Nervosa	Male; 30 y.o.; 5’10” Highest weight: 180 lbs Current weight: 140 lbs, BMI = 20.1 (normal) Duration of illness: 2 years; restriction, overexercise	WS = 40 This patient is currently at a normal BMI; however for a man of this height, he is at risk of losing more weight given the cognitive and behavioural features of his ED. If we are considering WS and current BMI, we might say he is at a normal BMI, but we have no cutoff to determine if this is an unhealthy amount of WS that might impact his clinical profile going forward.	Need for assessment of weight history/WS: With a 40lb weight loss, this patient may present with a fear based in learning history of returning to a premorbid weight. In this case, screening for weight history is very important; presenting at a normal weight within standard medical appointments (e.g., in primary care), this patient would not necessarily be screened for potential ED.
Bulimia Nervosa  (with developmental considerations)	Female; 11 y.o.; 4’3” Highest weight: 92 lbs (1 year ago) Current weight: 83 lbs, BMI = 22.4 (normal) Duration of illness: 1 year; binge eating and purging, average 3 times per day	WS = 9 This patient is not at her adult height (her pediatrician estimates projected height of 5’8”). Considering her age and expected growth, she is at high risk for endocrine dysfunction and menstrual disorder, as well as issues with bone density and growth.	Consider Using Difference in Weight %ile, according to a growth curve: Patient has history of above 97th %ile in weight for her age, obese BMI by both pediatric and adult standards. Currently she is at an overweight BMI by childhood BMI percentile standards; as she continues to grow, she will experience greater WS. She has likely been commended by medical professionals, family and friends, for her weight loss. Any treatment provider should consider both her weight history, as well as her relative growth in guiding clinical recommendations for both weight maintenance, and eating disorder prevention.
Anorexia Nervosa  (with developmental considerations)	Female; 24 y.o.; 5’8” Highest weight: 119 lbs Current weight: 109 lbs, BMI = 16.6 (underweight) Duration of illness: 10 years; binge-purge presentation	WS = 10 This patient has had a lower weight throughout her early adult life, and has maintained a weight within the “underweight” BMI category for several years. Whilst her BMI of 16.6 was within a normal range at age 12 (even with a 10lb weight loss), she has transitioned to underweight status over time even as she maintained this weight. Whilst weight suppression from age 14 “highest ever weight at adult height” is 10lb, expected weight as an adult would be higher.	Consider longer-term metabolic dysfunction, lack of true data point for expected adult weight: Being weight suppressed for 10 years, and never having achieved normal weight as an emerging or young adult, this patient may have more pronounced metabolic factors that influence her weight gain, and maintenance of symptoms in treatment.