EAL

ONC: Malnutrition Screening and Nutrition Assessment of Adult Oncology Patients (2012)

Citation:

Bauer J, Capra S. Comparison of a malnutrition screening tool with subjective global assessment in hospitalised patients with cancer: Sensitivity and specificity. Asia Pac J Clin Nutr. 2003; 12(3): 257-260.

Study Design:

Cross-Sectional Study

Class:

D - Click here for explanation of classification scheme.

Quality Rating:

NEUTRAL: See Quality Criteria Checklist below.

Research Purpose:

To assess the sensitivity and specificity of the malnutrition screening tool published by the the Malnutrition Advisory Group (MAG), a standing committee of The British Association of Parenteral and Enteral Nutrition against the subjective global assessment (SGA) in hospitalized patients with cancer.

Inclusion Criteria:

Patients age 18 years of age or more
Admitted to the oncology ward of a tertiary private Australian hospital over a three-month time period
Agree to participate in the study.

Exclusion Criteria:

See inclusion criteria.

Description of Study Protocol:

Recruitment

All patients 18 years of age or more who were admitted to the oncology ward of a tertiary private Australian hospital were recruited for the study.

Design

Study patients were evaluated using the SGA and MAG screening tools by experienced dietitians
SGA is based on the medical history (weight change, dietary intake chance, gastrointestinal symptoms that have persisted for more than two weeks, changes in functional capacity) and physical examination (loss of subcutaneous fat, muscle wasting, ankle or sacral edema and ascites). The medical history accounts for 60% and the physical examination accounts for 40% of the assessment. Patients are classified subjectively as either:
- Well nourished (SGA A)
- Moderately or suspected of being malnourished (SGA B)
- Severely malnourished (SGA C).
MAG nutrition screening tool is evaluated by body mass index (BMI) and percentage unintentional weight loss in the previous six months. Information on age, gender and diagnosis was obtained from the medical record.
- High risk: BMI less than 18.5kg/m² or BMI between 18.5 and 20kg/m² plus weight loss of 5% to 10 %
- Medium risk: BMI between 18.5 and 20kg/m²and less than 5 % weight weigh loss (or weight gain) or BMI higher than 20kg/m² and weight loss of 5% to 10%
- Low risk: BMI higher than 20kg/m² and weight loss less than 5% (or weight gain)
A contingency table was used to determine the sensitivity, specificity and predictive value of the MAG nutrition screening tool compared to SGA.

Intervention

A dietitian experienced in performing SGA assessed each patient according to standard guidelines using a predetermined proforma
Risk of malnutrition was determined by an independent experienced dietitian using the guidelines accompanying the MAG nutrition screening tool and proforma
Body mass index and percentage unintentional weight loss in the previous six months were determined.

Statistical Analysis

A contingency table was used to determine the sensitivity, specificity and predictive value of the MAG nutrition screening tool compared to SGA. Linear regression was used to examine the linear trend between age, BMI and percentage weight loss in the previous six months for each SGA classification.

Data Collection Summary:

Timing of Measurements

Subjects were evaluated during a three-month period of time.

Dependent Variables

Malnutrition.

Independent Variables

SGA category
MAG nutrition screen tool assessment.

Description of Actual Data Sample:

Initial N: 65 patients; 60% (39) were male and 40% (26) female
Attrition (final N): Same as initial
Age: Mean age (SD) was 56.4 (15.2) years
Other relevant demographics: All were admitted to a private, teritiary care hospital in Australia
Anthropometrics:
- Major demographics were 49% lymphoma and 13% breast cancer
- BMI (kg/m²): 24.4±4.8 (Mean SD)
- Weight loss (%): 4.7 (0.0 to 26.1) (Median and range)
Location: Australia.

Summary of Results:

Key Findings

Age, Percentage Weight Loss in Previous Six Months and Body Mass Index for Subjective Global Assessment (SGA) Classification in 65 Hospitalized Patients with Cancer

	SGA A (Well Nourished)	SGA B (Moderately Malnourished)	SGA C (Severely Malnourished)	P-value
Age (years) ±SD	49.9±14.0	56.1±15.0	71.0±8.0	0.02
Percentage weight loss in previous six months mean ±SD	2.3±4.2	6.4±4.8	13.9±9.2	<0.001
Body mass index (kg/m²) mean ±SD	26.2±4.0	24.5±4.9	19.4±2.2	0.002

Other Findings

Classification of the MAG Screening Tool Against the SGA

	Malnourished (SGA B + C)	Well Nourished (SGA A)
At risk of malnutrition (MAG nutrition screening tool: Medium and high risk)	29 (true positive)	4 (false positive)
Not at risk (MAG nutrition screening tool: Low risk)	20 (false negative)	12 (true negative)

18% (12) of 65 patients were correctly classified by the MAG nutrition screening tool as being well nourished (true negatives) and 45% (29) of patients were correctly classified as being malnourished (true positives)
31% (20) of patients were misclassified as being well nourished (false negatives) and 6% (four) of patients were misclassified as being malnourished (false positives)
The MAG nutrition screening tool had a sensitivity of 59% and specificity of 75%
The positive predictive value was 88% and the negative predictive value 38%.

Author Conclusion:

The low sensitivity and specificity of the MAG nutrition screening tool suggest that it is not a suitable screening tool for detecting risk of malnutrition in hospitalized patients with cancer.

Funding Source:

University/Hospital:

Center for Public Health Research, Queensland University of Technology, Brisbane, Australia

Not-for-profit

The Wesley Research Institute

Reviewer Comments:

Cross-sectional analysis of malnutrition in a group of patients with cancer. Found that MAG was not a sensitive, specific indicator of malnutrition compared to the SGA.

Quality Criteria Checklist: Primary Research
Relevance Questions
	1.	Would implementing the studied intervention or procedure (if found successful) result in improved outcomes for the patients/clients/population group? (Not Applicable for some epidemiological studies)	Yes
	2.	Did the authors study an outcome (dependent variable) or topic that the patients/clients/population group would care about?	Yes
	3.	Is the focus of the intervention or procedure (independent variable) or topic of study a common issue of concern to dieteticspractice?	Yes
	4.	Is the intervention or procedure feasible? (NA for some epidemiological studies)	Yes

Validity Questions
1.	Was the research question clearly stated?		Yes
	1.1.	Was (were) the specific intervention(s) or procedure(s) [independent variable(s)] identified?	Yes
	1.2.	Was (were) the outcome(s) [dependent variable(s)] clearly indicated?	Yes
	1.3.	Were the target population and setting specified?	Yes
2.	Was the selection of study subjects/patients free from bias?		No
	2.1.	Were inclusion/exclusion criteria specified (e.g., risk, point in disease progression, diagnostic or prognosis criteria), and with sufficient detail and without omitting criteria critical to the study?	No
	2.2.	Were criteria applied equally to all study groups?	Yes
	2.3.	Were health, demographics, and other characteristics of subjects described?	No
	2.4.	Were the subjects/patients a representative sample of the relevant population?	???
3.	Were study groups comparable?		No
	3.1.	Was the method of assigning subjects/patients to groups described and unbiased? (Method of randomization identified if RCT)	N/A
	3.2.	Were distribution of disease status, prognostic factors, and other factors (e.g., demographics) similar across study groups at baseline?	???
	3.3.	Were concurrent controls or comparisons used? (Concurrent preferred over historical control or comparison groups.)	N/A
	3.4.	If cohort study or cross-sectional study, were groups comparable on important confounding factors and/or were preexisting differences accounted for by using appropriate adjustments in statistical analysis?	No
	3.5.	If case control study, were potential confounding factors comparable for cases and controls? (If case series or trial with subjects serving as own control, this criterion is not applicable.)	No
	3.6.	If diagnostic test, was there an independent blind comparison with an appropriate reference standard (e.g., "gold standard")?	N/A
4.	Was method of handling withdrawals described?		Yes
	4.1.	Were follow-up methods described and the same for all groups?	Yes
	4.2.	Was the number, characteristics of withdrawals (i.e., dropouts, lost to follow up, attrition rate) and/or response rate (cross-sectional studies) described for each group? (Follow up goal for a strong study is 80%.)	Yes
	4.3.	Were all enrolled subjects/patients (in the original sample) accounted for?	Yes
	4.4.	Were reasons for withdrawals similar across groups?	N/A
	4.5.	If diagnostic test, was decision to perform reference test not dependent on results of test under study?	N/A
5.	Was blinding used to prevent introduction of bias?		No
	5.1.	In intervention study, were subjects, clinicians/practitioners, and investigators blinded to treatment group, as appropriate?	N/A
	5.2.	Were data collectors blinded for outcomes assessment? (If outcome is measured using an objective test, such as a lab value, this criterion is assumed to be met.)	N/A
	5.3.	In cohort study or cross-sectional study, were measurements of outcomes and risk factors blinded?	No
	5.4.	In case control study, was case definition explicit and case ascertainment not influenced by exposure status?	N/A
	5.5.	In diagnostic study, were test results blinded to patient history and other test results?	N/A
6.	Were intervention/therapeutic regimens/exposure factor or procedure and any comparison(s) described in detail? Were interveningfactors described?		???
	6.1.	In RCT or other intervention trial, were protocols described for all regimens studied?	N/A
	6.2.	In observational study, were interventions, study settings, and clinicians/provider described?	No
	6.3.	Was the intensity and duration of the intervention or exposure factor sufficient to produce a meaningful effect?	Yes
	6.4.	Was the amount of exposure and, if relevant, subject/patient compliance measured?	N/A
	6.5.	Were co-interventions (e.g., ancillary treatments, other therapies) described?	No
	6.6.	Were extra or unplanned treatments described?	No
	6.7.	Was the information for 6.4, 6.5, and 6.6 assessed the same way for all groups?	Yes
	6.8.	In diagnostic study, were details of test administration and replication sufficient?	N/A
7.	Were outcomes clearly defined and the measurements valid and reliable?		Yes
	7.1.	Were primary and secondary endpoints described and relevant to the question?	N/A
	7.2.	Were nutrition measures appropriate to question and outcomes of concern?	Yes
	7.3.	Was the period of follow-up long enough for important outcome(s) to occur?	???
	7.4.	Were the observations and measurements based on standard, valid, and reliable data collection instruments/tests/procedures?	Yes
	7.5.	Was the measurement of effect at an appropriate level of precision?	Yes
	7.6.	Were other factors accounted for (measured) that could affect outcomes?	???
	7.7.	Were the measurements conducted consistently across groups?	Yes
8.	Was the statistical analysis appropriate for the study design and type of outcome indicators?		Yes
	8.1.	Were statistical analyses adequately described and the results reported appropriately?	Yes
	8.2.	Were correct statistical tests used and assumptions of test not violated?	Yes
	8.3.	Were statistics reported with levels of significance and/or confidence intervals?	Yes
	8.4.	Was "intent to treat" analysis of outcomes done (and as appropriate, was there an analysis of outcomes for those maximally exposed or a dose-response analysis)?	N/A
	8.5.	Were adequate adjustments made for effects of confounding factors that might have affected the outcomes (e.g., multivariate analyses)?	No
	8.6.	Was clinical significance as well as statistical significance reported?	Yes
	8.7.	If negative findings, was a power calculation reported to address type 2 error?	Yes
9.	Are conclusions supported by results with biases and limitations taken into consideration?		Yes
	9.1.	Is there a discussion of findings?	Yes
	9.2.	Are biases and study limitations identified and discussed?	Yes
10.	Is bias due to study's funding or sponsorship unlikely?		Yes
	10.1.	Were sources of funding and investigators' affiliations described?	Yes
	10.2.	Was the study free from apparent conflict of interest?	Yes