Calculators & Tools

Anorexia Nervosa

DSM-5 criteria - restriction of energy intake with fear of weight gain.

1 What is the Anorexia Nervosa?

The Anorexia Nervosa is a psychosocial scoring tool used in paediatric practice. DSM-5 criteria - restriction of energy intake with fear of weight gain. It scores 3 criteria and interprets the total across 2 bands, so the number always arrives with the severity it implies rather than on its own. In PediAid each criterion is shown as a labelled option with the weight it carries, so the total can be checked rather than taken on trust.

2 When to use it

  • Grading severity at the bedside in psychosocial
  • Recording an objective severity band in the case notes
  • Deciding when a total crosses the threshold for escalation
  • Re-scoring to track whether a child is improving or deteriorating
  • Checking the exact criteria of a score used infrequently

3 Formula & method

The score sums 3 criteria: Restriction of energy intake leading to significantly low body weight for age, sex and health; Intense fear of gaining weight or becoming fat, or persistent behaviour that interferes with weight gain; Disturbance in the way body weight/shape is experienced, undue influence on self-evaluation, or lack of recognition of the seriousness of low weight. Totals are then banded: any score - Below threshold: not all 3 criteria met; 3 criteria met or more - Threshold met: all 3 criteria met - consistent with anorexia nervosa. Specify restricting vs binge-eating/purging type. Assess medical stability (bradycardia, orthostasis, electrolytes) urgently.
  • DSM-5 threshold: 3 or more of the 3 criteria listed.
  • A diagnosis also requires clinically significant distress or impairment, the required duration, and exclusion of substance use or another condition. Screening aid only - not a diagnosis.
  • In children, "significantly low weight" includes failure to make expected weight gain along the growth trajectory.

4 Frequently asked questions

How many criteria does the Anorexia Nervosa use?

3. They are Restriction of energy intake leading to significantly low body weight for age, sex and health; Intense fear of gaining weight or becoming fat, or persistent behaviour that interferes with weight gain; Disturbance in the way body weight/shape is experienced, undue influence on self-evaluation, or lack of recognition of the seriousness of low weight.

What do the bands of the Anorexia Nervosa mean?

The total is interpreted as: any score - Below threshold: not all 3 criteria met; 3 criteria met or more - Threshold met: all 3 criteria met - consistent with anorexia nervosa. Specify restricting vs binge-eating/purging type. Assess medical stability (bradycardia, orthostasis, electrolytes) urgently.

Does the score replace clinical judgement?

No. It is a structured way to record and communicate severity. A clinician concerned about a child should act on that concern regardless of the total.

Where does this score come from?

DSM-5 threshold: 3 or more of the 3 criteria listed.

Does it work offline?

Yes. Score definitions are bundled with the PediAid app, so the score computes without a connection.

For qualified clinicians. This page and the PediAid app are a clinical aid only. Calculations and reference data must be verified against the patient's clinical context, the source guideline and your local protocols before any treatment decision is made.