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MUST Score

Malnutrition Universal Screening Tool

A validated five-step malnutrition screening tool developed by BAPEN. Identifies adults at risk of malnutrition using BMI, percentage weight loss, and acute illness effect. Applicable across hospital, community, and care home settings.

MalnutritionNutrition ScreeningBAPENHospital & Community
MUST Calculator

Optional: enter height & weight to auto-calculate BMI score.

Enter height & weight to auto-calculate BMI score
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MUST Score

MUST Scoring Components

MUST Score = BMI Score + Weight Loss Score + Acute Illness Score

Step 1 — BMI:
BMI > 20 = 0 pts  |  BMI 18.5–20 = 1 pt  |  BMI < 18.5 = 2 pts

Step 2 — Unplanned weight loss (past 3–6 months):
<5% = 0 pts  |  5–10% = 1 pt  |  >10% = 2 pts

Step 3 — Acute illness effect:
If patient is acutely ill AND has had or is likely to have no nutritional intake for >5 days: 2 pts

If height and weight cannot be measured, use surrogate measures: mid-upper arm circumference (MUAC) or subjective clinical impression (very thin, thin, acceptable, overweight).

Risk Classification & Actions

MUST ScoreRiskRecommended Action
0 Low Risk Routine clinical care. Repeat screening: weekly (hospital), monthly (care home), annually (community).
1 Medium Risk Observe and monitor. Document dietary intake for 3 days. If improving or adequate, continue screening. If no improvement, refer to dietitian per local policy.
≥ 2 High Risk Treat — refer to dietitian or implement local nutritional support policy. Set goals, improve and increase overall nutritional intake. Monitor and review care plan: weekly (hospital), monthly (care home).

Clinical Application

  • Settings: MUST is validated for use in hospital inpatients, community (GP practice, outpatient clinic), and care homes. It has been adopted as the standard nutritional screening tool in the UK (NICE, BAPEN) and is widely used internationally.
  • Re-screening intervals: Hospital — every week; Care homes — every month; Community — every year, or if clinical condition changes (e.g., new illness, significant weight change).
  • Limitations: MUST does not capture muscle wasting (sarcopenia), micronutrient deficiencies, or inflammation. It should be complemented by clinical assessment. In ICU patients or those unable to report weight history, NRS-2002 or NUTRIC score may be more appropriate.
  • Obesity and malnutrition: Patients with a high BMI may still have significant unintentional weight loss and be at nutritional risk. MUST can identify malnutrition risk even in obese patients.
  • MUST vs. NRS-2002: MUST is simpler and better suited to community settings. NRS-2002 is preferred in hospital inpatients, particularly surgical and gastrointestinal patients, due to its disease severity weighting.

References

  1. Stratton RJ, Hackston A, Longmore D, et al. Malnutrition in hospital outpatients and inpatients: prevalence, concurrent validity and ease of use of the 'Malnutrition Universal Screening Tool' (MUST) for adults. Br J Nutr. 2004;92(5):799–808.
  2. British Association for Parenteral and Enteral Nutrition (BAPEN). The 'MUST' Report: Nutritional Screening of Adults: A Multidisciplinary Responsibility. BAPEN, 2003.
  3. NICE. Nutrition support for adults: oral nutrition support, enteral tube feeding and parenteral nutrition. Clinical guideline [CG32]. 2006, updated 2017.

Related Calculators

NRS-2002 BMI / BSA / IBW Prognostic Nutritional Index