REVISED WATERLOW - USE OF MST
Several people have asked the question:
Why has the nutritional element of the Waterlow pressure ulcer risk assessment
scoring system used the Australian Malnutrition Screening tool ‘MST’1, in
preference to the UK ‘MUST’2 when it was revised earlier this year?
To appreciate ‘why’, the background of the revision must be understood:
1. Over 6 years ago, I was approached by Nancy Magazinovic a Director of
Nursing at Prince Charles Hospital in Brisbane for permission to use
‘Waterlow’ in a Resource Guidelines which Queensland Health had been
funded by the Queensland Government to produce3.
2. They had selected ‘Waterlow’ after an internal review of Braden, Norton &
Waterlow and had decided on the basis of the evidence that Waterlow was
the most appropriate.
3. As it is many years since Waterlow was designed they were intending to
review the system in the light of modern nursing practices and asked me
whether I would be willing to work with their team. I readily agreed and
when Nancy was in Europe, presenting a paper at the European Wound
Care Conference, she took the opportunity to come to England, where she
stayed with me so we were able to spend a few days thoroughly going
through the areas which we considered would benefit from a review.
4. One of these areas was ‘Appetite’. Over the years I have been convinced
that nutrition is an important parameter in any risk assessment system.
5. A couple of years into the study I was in Australia visiting my daughter
south of Sydney and was invited to fly up to Brisbane to meet the project
team and discuss various aspects of the work in progress. I was also invited
to give a talk on pressure ulcer prevention at the Prince Charles Hospital.
6. Not surprisingly Nancy and her team opted to use MST for the nutritional
parameter to replace ‘Appetite’ when the validation process was conducted
in various trials, in all areas, across Queensland.
7. The MST was developed by a team from the Centre for Public Health
research, Queensland University of Technology Brisbane, the Nutrition
Services Department, The Wesley Hospital Brisbane, and the Nutrition and
Dietetics Department of the Radcliffe Hospital, Radcliffe, Australia1. The
abstract of the research paper states that ‘convergent and predictive validity
of the MST was established and the inter-rater reliability was high (9397%)’
8. Whether this is more, or less, accurate than MUST is irrelevant. What is
important is that Nancy and her team have validated ‘revised Waterlow’
with the MST as a replacement for ‘Appetite’ on the original scoring
system.
9. In my opinion there should be no confusion. MUST should be used for
what it was evaluated for – a comprehensive tool to identify a risk of poor
protein-energy status. There is no evidence to suggest that it would, or
would not, be a valid replacement for ‘Appetite’ in Waterlow.
10. If we are talking in the practical world of the day to day care of people,
rather than an academic discussion there will be very little difference
between the Waterlow ‘risk status’ level if a MUST score is used as the
nutritional element of the overall score whichever system is used. Using
MST the score will cover a range of 0 – 5. Using MUST the score will
cover a range of 0 – 6. The assessment of pressure ulcer risk, using
Waterlow, should not be seen as just a mathematical summation of
numbers. An assessment should be conducted, parameter by parameter,
using professional judgement to determine whether any individual risk
element can be alleviated. When a total score and risk status have been
established, taking into account all the circumstances of the individual
person, and the environment in which they are being cared for, action
should be taken – and documented, to ensure, as far as is possible, that the
development of a pressure ulcer is prevented.
11. It has been suggested that if MUST is part of a Hospital Policy then
patients cannot be assessed for their risk of developing pressure ulcers
using Waterlow, because Waterlow uses MST. I find this quite surprising,
as previous to the latest revision, there appeared to be no problem using
MUST, with Waterlow when Waterlow had ‘Appetite’ as the nutritional
parameter of the scoring system.
References:
1. Ferguson M, Capra S, Bauer J: Development of a valid and reliable malnutrition screening tool for
adult acute hospital patients – Nutrition Vol.15, No.6, 1999 (More information can be obtained
from Maree Ferguson mferguson@wesley.com.au )
2. BAPEN 2003 ISBN 1 899467 70 X: The ‘MUST’ Report
3. The State of Queensland, Queensland Health 2004 ISBN 0-7345-2982-1: Pressure ulcer prevention
& management resource guidelines. (A presentation of the work leading up to the publication of the
document is due to be made by Nancy Magazinovic Dir. Of Nursing at Prince Charles Hospital,
Brisbane at the Australian Wound Management Association Conference in March 2006)