Exploring: What is the best screening tool for malnutrition?

October 10, 2025 •

5 min read

Malnutrition affects up to 50% of hospitalized patients and is associated with longer hospital stays, increased complications, and higher mortality. Identifying at-risk individuals early is crucial, which raises the question: what is the best screening tool for malnutrition?

Quick Summary

This article provides a detailed comparison of several leading malnutrition screening tools, including MUST, NRS-2002, and MNA-SF. It discusses their applications in various care settings, outlines key assessment parameters, and guides healthcare professionals in selecting the most appropriate tool based on patient needs and clinical environment.

Key Points

No Single 'Best' Tool: The optimal malnutrition screening tool depends on the patient's age, clinical setting, and specific needs, not a universal standard.
MUST for All Adults: The Malnutrition Universal Screening Tool (MUST) is a versatile, 5-step tool suitable for general adult populations across various care settings.
NRS-2002 for Hospitalized Patients: The Nutritional Risk Screening 2002 (NRS-2002) is recommended for hospitalized patients, as it incorporates disease severity and predicts response to nutritional support.
MNA-SF for Older Adults: The Mini Nutritional Assessment Short Form (MNA-SF) is the most validated and accurate tool specifically for elderly individuals (≥65 years).
MST for Quick Screening: The two-question Malnutrition Screening Tool (MST) is the fastest option for initial, rapid assessment in various settings.
Screening Needs Follow-up: An effective screening process must be linked to a clear care pathway, including further assessment by a dietitian, intervention, and monitoring.
Early Intervention Improves Outcomes: Timely identification and treatment of malnutrition can significantly reduce hospital stays, complications, and mortality.

The Importance of Early Malnutrition Screening

Nutritional screening is the first and most critical step in addressing malnutrition in any healthcare setting. Early identification of nutritional risk allows for timely intervention, which has been shown to improve patient outcomes, such as faster wound healing, shorter hospital stays, and reduced mortality. Without a systematic screening process, a significant portion of at-risk individuals may go undetected and untreated.

Screening tools are designed to be quick and easy to administer, allowing for assessment by various trained personnel, not just dietitians. The optimal tool, however, is not a one-size-fits-all solution, but rather one that is chosen based on the specific patient population, clinical setting, and desired balance of sensitivity and practicality.

Leading Malnutrition Screening Tools for Adults

MUST (Malnutrition Universal Screening Tool)

Developed by the British Association for Parenteral and Enteral Nutrition (BAPEN), MUST is a five-step, evidence-based tool applicable to all adults across hospitals, communities, and care homes.

Step 1: BMI Score: Calculate the patient’s Body Mass Index (BMI).
Step 2: Weight Loss Score: Assess the percentage of unplanned weight loss over the last 3-6 months.
Step 3: Acute Disease Effect Score: Consider if there has been or is likely to be no nutritional intake for more than 5 days.
Step 4: Overall Risk Score: Add the scores from the first three steps.
Step 5: Management Guidelines: Develop a care plan based on the final risk score (Low, Medium, or High).

NRS-2002 (Nutritional Risk Screening 2002)

Recommended by the European Society for Clinical Nutrition and Metabolism (ESPEN) for hospitalized adults, NRS-2002 is particularly robust for identifying patients who will benefit from nutritional support. It incorporates a two-part process.

Initial Pre-Screening: Four questions check for a low BMI (<20.5), recent weight loss, reduced intake, and acute illness. If any answer is yes, the main screening proceeds.
Main Screening: This part scores the severity of nutritional impairment and disease severity on a scale of 0-3 each. An extra point is added for patients aged 70 or older. A total score of 3 or more indicates a risk of malnutrition.

MNA-SF (Mini Nutritional Assessment Short Form)

Specifically designed and validated for assessing malnutrition risk in older adults (≥65 years), the MNA-SF is a widely used and highly accurate tool. It is a six-item questionnaire that covers multiple aspects of a patient’s health and lifestyle.

Food intake decline over the last 3 months.
Weight loss over the last 3 months.
Mobility.
Psychological stress or acute disease in the last 3 months.
Neuropsychological problems (dementia, depression).
BMI, with an option to use calf circumference if height or weight is unavailable.

MST (Malnutrition Screening Tool)

This is one of the simplest screening tools, suitable for a wide range of adult patients in acute and community settings. It consists of just two questions:

Have you lost weight recently without trying?
Have you been eating less than usual because of a poor appetite?

Comparison of Malnutrition Screening Tools


Feature	MUST	NRS-2002	MNA-SF	MST
Target Population	General Adult Population	Hospitalized Adults	Older Adults (≥65 years)	Broad Adult Population
Key Parameters	BMI, Unplanned Weight Loss, Acute Disease Effect	BMI, Weight Loss, Food Intake, Disease Severity, Age	Food Intake, Weight Loss, Mobility, Stress, Neuro Problems, BMI/Calf Circ.	Unplanned Weight Loss, Appetite
Scoring	0-6 (Low, Medium, High Risk)	0-7 (≥3 indicates risk)	0-14 (12-14 normal, 8-11 at risk, 0-7 malnourished)	0-5 (≥2 indicates risk)
Use Case	Wide range of settings, general screening	Hospitalized patients, identifies benefit from nutritional support	Geriatric patients, especially valuable in community and long-term care	Quick, simple screening in any setting
Reliability/Validity	Very good to excellent validity and reproducibility demonstrated	Well-validated, strong predictor of outcomes	Most validated tool for the elderly	High sensitivity and widely applicable

Factors for Choosing the Right Screening Tool

Selecting the best tool depends on the context. Consider the following factors when making a decision:

Patient Population: For geriatric patients, MNA-SF is often the most comprehensive and accurate choice. For general adult admissions, MUST or NRS-2002 are suitable, while MST offers the fastest screening option.
Clinical Setting: Hospital settings often favor NRS-2002 for its focus on hospitalized patients and disease severity, while MUST is easily integrated into both hospital and community-based protocols. MST’s simplicity is ideal for rapid screening in any setting.
Practicality: The ease of use, time required, and necessary training for staff are key considerations. The two-question MST is the fastest, but may be less sensitive than a more comprehensive tool like NRS-2002.
Purpose: Determine if the goal is a rapid initial screen (MST), a robust predictor for intervention response (NRS-2002), or a comprehensive geriatric assessment (MNA-SF).
Evidence Base: Choose a tool that has been validated for your specific target population and clinical setting. All the tools mentioned are widely used and have a strong evidence base.

What happens after screening?

Screening is not a standalone activity. After an individual is identified as being at risk for malnutrition, a structured nutritional care pathway should be initiated. This includes:

Detailed Assessment: A registered dietitian conducts a more thorough assessment of the patient's nutritional status, dietary intake, and needs.
Intervention: A tailored nutrition support plan is developed, which may involve dietary counseling, oral nutritional supplements, or enteral/parenteral nutrition.
Monitoring: The patient's nutritional status is monitored regularly to evaluate the effectiveness of the intervention.
Documentation: The results and care plan are documented and communicated across all relevant care settings to ensure continuity.

Conclusion

There is no single best screening tool for malnutrition across all situations. The effectiveness of a tool is highly dependent on the patient population and clinical context. For hospitalized adults, the NRS-2002 is often the recommended choice due to its prognostic ability regarding treatment outcomes. In geriatric care, the MNA-SF stands out for its high validity and comprehensive approach. For general-purpose and rapid screening, MUST offers an excellent, widely applicable option. By understanding the strengths of each tool and considering the specific setting, healthcare professionals can select the most appropriate method to facilitate timely and effective nutritional interventions, ultimately improving patient care and outcomes. The key is to have a systematic screening process in place and to consistently follow up with appropriate nutritional support for at-risk individuals.

Frequently Asked Questions

Screening is a quick, initial process to identify individuals who are at risk of malnutrition. Assessment is a more detailed, in-depth evaluation, typically performed by a dietitian, for those flagged as at-risk during screening.

The Mini Nutritional Assessment Short Form (MNA-SF) is specifically designed and highly validated for older adults (65 and over), making it the most accurate tool for this population.

The frequency of screening depends on the setting. In hospitals, it should be done upon admission and reviewed at least weekly. In care homes, monthly screening is recommended, and in the community, it can be done annually or when there is clinical concern.

Most validated screening tools typically include parameters related to BMI or weight loss, changes in dietary intake, and the effect of acute disease.

No, screening tools are often validated for specific populations. For instance, MNA-SF is for the elderly, while tools like STRONGkids or PNST are used for pediatric patients. MUST and MST are applicable for general adults.

Early screening and intervention lead to better patient outcomes, including improved recovery rates, reduced length of hospital stay, and lower healthcare costs associated with malnutrition-related complications.

Some tools offer alternative measurements. For example, MNA-SF allows for calf circumference to be used as a proxy for BMI in older adults. Other tools may rely on subjective criteria or estimations from relatives.