What is the Malnutrition Universal Screening Tool (MUST)?
The Malnutrition Universal Screening Tool, or MUST, is a validated five-step process designed to identify adults who are malnourished, at risk of malnutrition (undernutrition), or obese. Developed by the British Association for Parenteral and Enteral Nutrition (BAPEN), MUST provides a structured and efficient method for assessing nutritional risk in various settings, including hospitals, community clinics, and care homes. Its simplicity and reliability make it an invaluable tool for healthcare workers, enabling early detection and management of nutritional issues to improve patient outcomes.
The Five Steps of the MUST Screening Process
The MUST screening process systematically gathers key data to determine a patient's nutritional risk and does not require complex clinical assessments.
Step 1: Body Mass Index (BMI) Score
Calculate the patient's BMI to assess current weight status. Points are assigned based on BMI value, with options for estimating BMI using mid-upper arm circumference (MUAC) if direct measurements are not possible.
Step 2: Weight Loss Score
Assess the percentage of unplanned weight loss over the past 3 to 6 months. Scores are assigned based on the severity of the weight loss.
Step 3: Acute Disease Effect Score
Account for the increased risk of malnutrition due to acute disease or poor nutritional intake for over five days. A score of 2 is assigned if this factor is present.
Step 4: Overall Risk of Malnutrition
Sum the scores from the first three steps to determine the overall MUST score and risk category: Low Risk (0), Medium Risk (1), and High Risk (2 or more).
Step 5: Management Guidelines
Apply relevant management guidelines based on the risk score, ranging from routine monitoring to referral for specialist nutritional support.
Comparison of Screening Tools: MUST vs. Other Tools
| Feature | Malnutrition Universal Screening Tool (MUST) | Malnutrition Screening Tool (MST) | Short Nutritional Assessment Questionnaire (SNAQ) |
|---|---|---|---|
| Number of Steps/Questions | 5 steps | 2-3 questions | 3-4 questions |
| Key Parameters | BMI, recent weight loss, acute disease effect | Recent weight loss, appetite | Recent weight loss, appetite, mobility |
| Identifies | Malnourished, at-risk (undernutrition), obese | Malnutrition risk | Malnutrition risk, anorexia in elderly |
| Primary Setting | Multi-setting (hospital, community, care homes) | Hospital, ambulatory, care homes | Hospitalized patients, community-dwelling elderly |
| Ease of Use | Moderate; requires measurements | Very easy and quick | Easy and quick |
| Key Strength | Comprehensive and includes obesity risk | Quick and simple to use | Quick, useful for assessing appetite |
| Primary Limitation | Potentially less applicable in practice due to data unavailability in some cases | Less comprehensive than MUST | May not be suitable for all patient populations |
Limitations and Considerations for MUST
MUST is not validated for children or patients with certain conditions like renal disease. It screens for protein-energy status but not vitamin/mineral deficiencies. Caution is needed for patients with fluid disturbances, amputations, or pregnancy, which affect weight/BMI.
How Healthcare Providers Use MUST
MUST screening is often performed upon admission and at regular intervals. Opportunistic screening occurs in outpatient settings. For medium or high-risk patients, Step 5 guides interventions like dietary changes, supplements, or specialist referrals. Consistent MUST use helps address nutritional problems early for better health outcomes.
Conclusion
The Malnutrition Universal Screening Tool (MUST) is a highly effective five-step screening tool to identify adults who are malnourished at risk of malnutrition undernutrition or obese. By assessing BMI, weight loss, and the impact of acute illness, it provides clear risk scores that guide management strategies. Despite some limitations, MUST is a key tool in proactive nutritional care across various settings, improving patient outcomes and quality of life.
Learn more about the tool and its use at the official website of the British Association for Parenteral and Enteral Nutrition (BAPEN).
