Using the SCOFF Questionnaire and Assessing Compensatory Behaviours in CASC Eating Disorder Stations

Eating disorder stations in the MRCPsych CASC require a structured, sensitive approach. Examiners expect you to demonstrate knowledge of validated screening tools like the SCOFF questionnaire and to systematically assess compensatory behaviours while maintaining compassionate, non-judgemental rapport. These can be among the most clinically challenging stations because patients often minimise symptoms and feel intense shame.

Why Eating Disorder Stations Appear in CASC

Eating disorders carry the highest mortality rate of any psychiatric illness, with anorexia nervosa having a standardised mortality ratio of approximately 5.9. They affect approximately 1.25 million people in the UK and are increasingly recognised across all age groups, genders, and ethnicities — not just the traditional stereotype of young white females. CASC stations assess your ability to screen systematically, explore sensitive topics without causing shame, identify medical risk, and communicate a management plan that addresses both psychiatric and physical needs.

Key Diagnostic Categories to Know

You should be able to distinguish between the main eating disorder diagnoses for CASC:

Anorexia Nervosa - Restriction of energy intake leading to significantly low body weight (BMI <17.5 kg/m² is a commonly used threshold, though diagnosis is clinical) - Intense fear of gaining weight or persistent behaviour that interferes with weight gain - Disturbance in body image — perceiving themselves as overweight despite being underweight - Subtypes: **restricting type** (dietary restriction and/or excessive exercise) and **binge-purge type** (restriction with episodes of binge eating and purging) - Severity grading by BMI: Mild (≥17), Moderate (16-16.99), Severe (15-15.99), Extreme (<15)

Bulimia Nervosa - Recurrent episodes of binge eating (eating a large amount of food in a discrete period with a sense of loss of control) - Recurrent compensatory behaviours to prevent weight gain: self-induced vomiting, laxative/diuretic misuse, fasting, excessive exercise - Binge-purge cycle occurs at least once a week for 3 months - Self-evaluation is unduly influenced by body shape and weight - The patient is typically of normal weight or slightly overweight (distinguishing feature from binge-purge anorexia)

Binge Eating Disorder (BED) - Recurrent episodes of binge eating (as defined above) - Binge eating episodes are associated with 3 or more of: eating more rapidly than normal, eating until uncomfortably full, eating large amounts when not hungry, eating alone due to embarrassment, feeling disgusted/depressed/guilty afterwards - Marked distress regarding binge eating - No regular compensatory behaviours (distinguishing feature from bulimia) - Often associated with obesity and metabolic complications

Avoidant/Restrictive Food Intake Disorder (ARFID) - Avoidance or restriction of food intake leading to weight loss, nutritional deficiency, or psychosocial impairment - NOT driven by body image concerns or fear of weight gain (distinguishing feature from anorexia) - May be related to sensory sensitivity, fear of aversive consequences (choking, vomiting), or lack of interest in eating - Increasingly recognised in children, adolescents, and adults with neurodevelopmental conditions

Atypical Presentations - Be aware that patients can present with significant eating disorder pathology without meeting full diagnostic criteria — these presentations still warrant assessment and treatment - Males, older adults, and patients from ethnic minority backgrounds may present atypically and are often under-diagnosed

The SCOFF Questionnaire Explained

The SCOFF questionnaire is a 5-question screening tool developed by Morgan, Reid, and Lacey (1999). It is recommended by NICE (CG9, updated NG69) and widely used in primary and secondary care. Each letter maps to a screening question:

• S — Sick: Do you make yourself Sick because you feel uncomfortably full? (screens for self-induced vomiting)
• C — Control: Do you worry you have lost Control over how much you eat? (screens for binge eating)
• O — One stone: Have you recently lost more than One stone (6.35 kg) in a 3-month period? (screens for significant weight loss)
• F — Fat: Do you believe yourself to be Fat when others say you are too thin? (screens for body image distortion)
• F — Food: Would you say that Food dominates your life? (screens for preoccupation with food)

Each "Yes" answer scores 1 point. A score of 2 or more indicates a likely eating disorder and warrants further assessment. The SCOFF has sensitivity of approximately 100% for anorexia nervosa and 87.5% for bulimia nervosa. It is a screening tool, not a diagnostic instrument — a positive score triggers further assessment, not a diagnosis.

Administering the SCOFF in a CASC Station

Do not fire through the five questions as a checklist. Instead, integrate them conversationally. Open with something like: "I would like to ask you some questions about your eating habits and how you feel about food. Some of these questions might feel quite personal, but they help me understand what you are going through. Is that okay?"

Tips for Natural Delivery - Use the patient's own language and concerns as a springboard: if they mention weight loss, follow up with the "One stone" question naturally - Acknowledge their answers empathically before moving on: "Thank you for telling me that. It sounds like that's been really difficult" - If a patient answers "yes" to any question, briefly explore before continuing — this shows you are listening, not just screening - Frame questions with normalising language: "Some people find that..." or "It is common for people to..." - If they answer "no" to everything but you have clinical suspicion, do not abandon the assessment — explore further with open questions about their relationship with food

Assessing Compensatory Behaviours

Compensatory behaviours are actions taken to counteract perceived overeating or to control weight. They are a hallmark of bulimia nervosa and binge-purge anorexia nervosa. Patients often feel intense shame and may not volunteer this information, so you must ask directly but sensitively.

Domains to Cover

1. Purging (self-induced vomiting) — Ask: "Some people find that after eating they feel the need to get rid of the food. Is that something you have experienced?" Explore frequency (times per day/week), duration (how long has this been happening), triggers (specific foods, emotional states, situations), method, and any physical consequences such as sore throat, dental problems, swollen cheeks, or blood in vomit.
2. Laxative and diuretic misuse — Ask: "Have you ever used laxatives, water tablets, or diet pills to manage your weight?" Explore the type (stimulant vs. osmotic laxatives), quantity (number per day), frequency, source (bought over-the-counter, prescribed, ordered online), duration of use, and escalation pattern.
3. Excessive exercise — Ask: "Do you ever feel driven to exercise, even when you are tired or unwell?" Look for: exercising despite injury or illness, distress if unable to exercise, exercise taking priority over social/work activities, exercising in secret, quantifying exercise by calories burned rather than enjoyment. Ask: "How much exercise are you doing in a typical week?" and "What happens if you can't exercise — how does that make you feel?"
4. Restrictive fasting — Ask: "Are there days when you deliberately skip meals or go without food for long periods?" Explore duration, frequency, and relationship to binge episodes (restriction often triggers binges).
5. Insulin manipulation (diabulimia) — In patients with Type 1 diabetes, screen for deliberate omission or reduction of insulin to lose weight. This is extremely dangerous and frequently missed. Ask: "Have you ever deliberately reduced or skipped your insulin?"
6. Other behaviours — Chewing and spitting food, use of appetite suppressants, caffeine pills, or illicit substances for weight control, rumination disorder (regurgitation and rechewing)

For each behaviour, systematically assess type, frequency, duration, triggers, escalation over time, and the patient's perceived control over the behaviour.

Assessing Binge Eating Episodes

If the patient reports binge eating, assess in detail:

• Quantity: "Can you describe what a typical binge looks like? What kind of food and how much?"
• Duration: "How long does an episode typically last?"
• Sense of control: "Do you feel you can stop once you've started?" (loss of control is the defining feature)
• Triggers: "What tends to set off an episode?" — emotional triggers (stress, loneliness, boredom, conflict), dietary triggers (prolonged restriction), situational triggers (being alone, specific times of day)
• Frequency: "How often does this happen? Daily? Weekly?"
• Emotional aftermath: "How do you feel after an episode?" — guilt, shame, disgust, self-loathing are typical
• Compensatory response: "What do you do after a binge?" — this determines whether the pattern is bulimia (compensatory behaviours) or BED (no regular compensation)
• Secrecy: "Do other people know about this?" — binge eating is often hidden, and secrecy indicates shame

Physical Complications and Risk Assessment

Examiners expect awareness of the medical risks of eating disorders and compensatory behaviours. This is often what distinguishes a pass from a fail in these stations — candidates who only address the psychology without considering the physical risks are marked down.

Key Physical Complications - **Cardiovascular:** Bradycardia (heart rate <60 bpm), hypotension, postural drop (>10 mmHg systolic on standing), prolonged QTc interval, cardiac arrhythmias (secondary to electrolyte disturbance), peripheral oedema (in refeeding), cardiac failure in extreme cases - **Metabolic:** Hypokalaemia (most dangerous — risk of cardiac arrest and renal damage), hyponatraemia, hypophosphataemia (refeeding syndrome risk), metabolic alkalosis (from vomiting) or acidosis (from laxative abuse), hypoglycaemia, dehydration - **Gastrointestinal:** Oesophageal tears (Mallory-Weiss syndrome) or rupture (Boerhaave syndrome — life-threatening), parotid gland swelling (giving a "chipmunk" appearance), dental enamel erosion (perimolysis — particularly of the palatal surfaces of upper anterior teeth), gastric dilation (rare but dangerous), gastroparesis, constipation, oesophagitis - **Musculoskeletal:** Osteopenia and osteoporosis (due to malnutrition and hypogonadism — DEXA scan recommended), proximal myopathy (from hypokalaemia) - **Endocrine/Reproductive:** Amenorrhoea (though no longer required for diagnosis), infertility, low oestrogen/testosterone, growth retardation in adolescents, hypothermia - **Dermatological:** Russell's sign (calluses on knuckles from self-induced vomiting), lanugo hair (fine downy hair on body — compensatory response to hypothermia), dry skin, brittle nails, hair loss - **Neurological:** Peripheral neuropathy (nutritional deficiency), cognitive impairment (malnutrition), seizures (electrolyte disturbance) - **Haematological:** Pancytopenia, leucopenia (reduced immune function)

Red Flags Requiring Urgent Medical Review Know these cold — they may appear in your CASC station as triggers for urgent action: - BMI below 13 kg/m² or rapid weight loss of more than 1 kg per week - Heart rate below 40 bpm or significant QTc prolongation - Systolic BP below 90 mmHg or postural drop >20 mmHg - Core temperature below 35°C - Blood glucose below 3.5 mmol/L - Significant electrolyte disturbance (especially potassium <3.0 mmol/L) - Syncope, seizures, or cardiac symptoms - Acute gastric dilation or haematemesis - Failed outpatient treatment with ongoing deterioration

Psychiatric Risk - Always screen for suicidal ideation — there is high comorbidity with depression (up to 70% of patients with anorexia nervosa experience comorbid depression) - Assess for self-harm (particularly cutting), which is common in bulimia nervosa and binge-purge anorexia - Substance misuse assessment — alcohol and stimulant misuse are common comorbidities, particularly in bulimia nervosa - Social isolation and functional impairment — eating disorders can be profoundly isolating - Reference the **MARSIPAN** (Management of Really Sick Patients with Anorexia Nervosa) guidelines for the medical management of acutely unwell patients — know that these guidelines exist and recommend admission for patients meeting high-risk criteria - **Junior MARSIPAN** for patients under 18

Motivational Interviewing in Eating Disorder Stations

Many eating disorder patients are ambivalent about change. This is not resistance — it is a core feature of the illness. Using motivational interviewing (MI) principles in your CASC station demonstrates sophisticated clinical skill:

Key MI Principles for Eating Disorder Stations - **Express empathy**: "I can see this is something you've struggled with for a long time. It takes real courage to talk about it" - **Develop discrepancy**: Explore the gap between their current behaviour and their values/goals. "You mentioned wanting to be well enough to go back to university. How does that fit with what's happening with your eating at the moment?" - **Roll with resistance**: If the patient minimises or denies, don't argue. "I hear that you don't feel there's a problem right now. I'm just concerned because the tests are showing some things that worry me" - **Support self-efficacy**: "You've managed to take the first step by coming here today. That tells me you have strength to make changes" - **Avoid the righting reflex**: Resist the urge to lecture or persuade — this increases resistance. Instead, ask open questions and let the patient articulate their own reasons for change

Phrases to Avoid - "You need to eat more" — oversimplifies a complex illness - "If you don't stop, you'll die" — fear-based approaches increase resistance and shame - "Just try to eat normally" — invalidates the severity of their struggle - "You look thin" — can be interpreted as a compliment and reinforce disordered behaviour

Management and Closing the Station

After completing your assessment, briefly outline a management plan. This demonstrates that you can translate assessment into action:

• Investigations: FBC (pancytopenia risk), U&Es (especially potassium — hypokalaemia has immediate lethal potential), LFTs, glucose, calcium, magnesium, phosphate (refeeding risk), TFTs (to exclude thyroid disease), ECG if purging or low weight (QTc prolongation, arrhythmias), bone profile, vitamin D, DEXA scan if amenorrhoea >6 months, urinalysis
• Physical observations: BMI calculation, heart rate, blood pressure lying and standing (postural drop), temperature, blood glucose, muscle power assessment (squat test — can they stand from a squat without using arms?)
• Referral: Specialist eating disorder service (essential — generalist management alone is insufficient), dietetic input, medical review if physically compromised
• Psychological therapy (NICE-recommended): CBT-ED for bulimia nervosa and binge eating disorder (first-line); individual eating disorder-focused CBT (CBT-ED), Maudsley Anorexia Nervosa Treatment for Adults (MANTRA), or specialist supportive clinical management (SSCM) for anorexia nervosa in adults; family-based treatment (FBT/Maudsley method) for children and adolescents with anorexia nervosa
• Pharmacological considerations: SSRIs (fluoxetine 60mg) can be adjunctive in bulimia nervosa; no medication has strong evidence for anorexia nervosa; avoid medications that lower seizure threshold or have cardiac effects
• Closing: Summarise findings, validate the patient's courage in discussing these issues ("I really appreciate you being so open with me today — I know these are difficult things to talk about"), provide realistic hope that eating disorders are treatable ("With the right help, many people make a full recovery"), outline clear next steps and arrange follow-up

Common Mistakes to Avoid

1. Being judgemental or expressing shock — Maintain a neutral, compassionate tone throughout, regardless of the severity of behaviours described
2. Only asking about restriction and ignoring compensatory behaviours — Systematically assess all domains: purging, laxatives, exercise, fasting, and insulin manipulation
3. Forgetting physical risk — Always screen for medical complications and know when to escalate. This is often what separates a pass from a fail.
4. Using the SCOFF as a checklist — Integrate questions conversationally and explore positive responses with follow-up questions
5. Failing to provide a management plan — Examiners expect you to formulate next steps including investigations, referral, and therapy options
6. Assuming the patient wants to change — Many patients are ambivalent or pre-contemplative. Use MI principles rather than assuming motivation.
7. Missing comorbidities — Screen for depression, anxiety, OCD, PTSD, and substance misuse, all of which commonly co-occur
8. Forgetting to calculate BMI — If weight and height are available, calculate BMI and state the severity category
9. Not asking about the impact on daily life — Functional impairment (social isolation, inability to work/study, impact on relationships) is important for both clinical formulation and treatment planning

Practice Checklist

• [ ] Can I recite the SCOFF questions from memory and explain the scoring?
• [ ] Can I distinguish between anorexia nervosa, bulimia nervosa, and binge eating disorder?
• [ ] Can I ask about purging, laxative use, and other compensatory behaviours sensitively and thoroughly?
• [ ] Do I systematically assess frequency, duration, type, triggers, and escalation for each behaviour?
• [ ] Can I list the key physical complications and red flags for urgent review from memory?
• [ ] Can I outline a management plan including investigations, referral, and NICE-recommended therapy options?
• [ ] Can I apply motivational interviewing principles with an ambivalent patient?
• [ ] Do I know when to reference MARSIPAN guidelines?
• [ ] Have I practiced this station type under timed conditions with realistic scenarios?