Are you using a validated malnutrition screening tool?

Any organisation that provides care to individuals must have a process to identify and treat those with malnutrition or who are at risk of malnutrition.

The simplest method of identifying malnutrition is to track weight and weight loss. However, this is notoriously inaccurate. Oedema may mask true weight loss and provides no additional information about the nutritional status for the individual person. For example, a 5kg weight loss in an individual who weighs only 50kg is far more significant than in a person who weighs 150kg. It does not take into consideration any comorbidities.

A formal and validated malnutrition screening tool is recommended.  A malnutrition screening tool is designed to readily identify those who may be at risk, so that a more comprehensive assessment can be undertaken and appropriate strategies to improve nutritional status can be implemented.

There are a variety of malnutrition screening and assessment tools that are commonly used. They include questions about current weight, body mass index, weight change, appetite and comorbidities, and assign a score indicating level of risk. They can help to identify those who are malnourished or at risk of malnutrition. The tool selected must be validated in the setting in which it is to be used and must be able to be easily implemented by staff. If a tool is difficult to implement then it will not be used routinely.

Some of the common screening tools are listed here

The selection of the best tool for the organisation should be a joint decision between nursing staff and the dietitian, taking into consideration the practical aspects of conducting the tool and ensuring that it is carried out regularly as determined.

Malnutrition screening should be conducted at regular intervals, depending on the specific setting. Weekly may be needed in acute care hospitals, but monthly or 3 monthly would be appropriate in long term care. Older individuals living at home should undergo malnutrition screening as part of their regular health care with their GP.

The person who performs malnutrition screening will depend on the organisation and setting. In a hospital a nutrition assistant or a member of the nursing staff may be responsible. In aged care the RN generally performs screening and in a GP practice the practice nurse is likely to be the responsible person. The screening process should be incorporated into standard processes to ensure that it is conducted routinely.

Note that for tools that use BMI a height measurement is required. It can be difficult to estimate height. Small differences in estimate can result in big changes to the screening tool score. There are various methods of estimating height, but measuring ulna length is relatively simple and height can be estimated using a formula or table.

Nutrition Assessment

It is important to recognise that a malnutrition screening tool is not a nutrition assessment - it simply identifies individuals at risk. A screening tool that incorporates a scoring system will provide a priority for referral for nutrition support.

Following screening a full nutrition assessment should be conducted by a dietitian if the resident is identified as high risk. Nutrition assessment involves a more comprehensive approach to assessing all factors that might impact on nutritional status and identify nutrition related issues.
The dietitian may use a variety of assessment tools, for example:

      MNA- full assessment

     Patient Generated Subjective Global Assessment

Pathways of Action

The screening tool itself is just the beginning. More important is the action to be taken when a resident is identified at risk. There must be very clear action pathways for staff regarding implementation of high protein high energy diets, nourishing fluids, supplements and referral to a dietitian.

The factors contributing to poor intake must be treated where possible. Everyone involved in the care of the person can play a part in encouraging food intake and improving nutrition. The causes of poor intake should be closely examined and corrected. In addition the role of the dining environment and other social factors should not be underestimated.

Some of the screening tools have been adapted by supplement companies and commercial supplements may be embedded in the pathways. Each hospital or aged care home should determine their own pathways. A Food First approach should be the first strategy and supplements used judiciously when warranted.

An Accredited Practising Dietitian who is experienced in the relevant setting must be used and can provide practical solutions.


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