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


Isenring E, Bauer J, Capra, S. The scored patient-generated subjective global assessment (PG-SGA) and its association with quality of life in ambulatory patients receiving radiotherapy. European Journal of Clinical Nutrition. 2003; 57, 305-309.

PubMed ID: 12571664
Study Design:
Cross-Sectional Study
D - Click here for explanation of classification scheme.
Quality Rating:
Positive POSITIVE: See Quality Criteria Checklist below.
Research Purpose:

To evaluate the use of the scored patient-generated subjective global assessment (PG-SGA) as a measure of nutritional status in ambulatory patients receiving radiotherapy to the head, neck, abdominal or rectal area and to determine if there is an association between the PG-SGA and quality of life (QOL) scores.

Inclusion Criteria:
  • 18 years of age and over
  • Commenced at least 20 fractions of radiotherapy to the head, neck, abdominal or rectal area
  • Treatment at two radiation oncology centers in Australia
  •  Informed written consent.
Exclusion Criteria:
  • Receiving enteral or parenteral nutrition
  • Requiring more than five days of hospitalization 
  • Non-English speaking
  • Emotional or cognitive problems.
Description of Study Protocol:


Recruited from two radiation oncology centers in Australia.


Subjects were assessed at baseline and after four weeks of radiotherapy treatment for quality of life and nutritional status. A researcher experienced in using the scored PG-SGA assessed all subjects and subjects were classified as either well-nourished, moderately or suspected of being malnourished, or severely malnourished. Each subject was assigned an SGA score and total PG-SGA score.

Statistical Analysis

  • Completed using SPSS version 10, 2000
  • Paired student's T-tests used to compare mean PG-SGA scores and global QOL scores at baseline and after four weeks of radiotherapy
  • T-tests to examine the association between PG-SGA, QOL and level of support
  • ANOVA tests to examine association between PG-SGA scores and global QOL scores for each SGA classification
  • Chi square test used to examine associations between PG-SGA and SGA
  • Correlation analysis to examine association between PG-SGA score and global QOL score
  • Linear regression to examine linear trend for PG-SGA and QOL and SGA classification
  • General linear modeling to determine amount of variation in QOL attributable to PG-SGA accounting for gender, age, level of support, BMI, percentage weight loss in the past six months and baseline PG-SGA
  • Statistical significance reported at P<0.05 level
  • Power adequate for study at greater than 90%.
Data Collection Summary:

Timing of Measurements

For SGA and PG-SGA:

  • Age, gender, treatment and diagnosis obtained from medical record
  • Measures completed at baseline and after four weeks of radiotherapy
    • Height and weight
    • Family, friend and caretaker support was assessed during interview
    • PG-SGA
    • EORTC QLQ-C30 used to assess QOL.

Dependent Variables

  • Change in PG-SGA score
  • Change in EORTC QLQ-C30 score.

Independent Variables

  • Four weeks of radiotherapy
  • SGA score.

Control Variables

  • Age
  • Gender
  • Body mass index (BMI)
  • Percentage weight loss in previous six months
  • Type of cancer
  • Family, friend and caretaker support. 
Description of Actual Data Sample:
  • Initial N: 60 subjects (51 male, nine female)
  • Attrition (final N): 57 subjects
  • Age: 61.9+14 years
  • Other relevant demographics:
    • Radiotherapy treatment are:
      • Head and neck: 88%
      • Abdomen and rectum:12%
    • Treatment timing:
      • 47% treated with post-operative radiotherapy
      • 3% received pre-operative radiotherapy
      • 50% received radiotherapy only with no plans for surgery
  • Anthropometrics:
    • BMI: 25.8+4.5kg/m2
    • Nutritional status as measured by SGA
      • SGA A (well nourished): 65% (39 subjects)
      • SGA B (suspected or moderately malnourished): 28% (17 subjects)
      • SGA C (severely malnourished): 7% (four subjects)
  • Location: Two radiation oncology centers in Australia.
Summary of Results:

 Key Findings

  • Significant linear trend between PG-SGA scores for each of the SGA classifications (P<0.001)
  • Significant correlation between PG-SGA score and global QOL at baseline (R= -0.66, P<0.001)
  • Significant decrease in nutritional status according to the PG-SGA score (t(56)= -5.79, P<0.001) and SGA (x2=37.58, P<0.001) after four weeks of radiotherapy
  • According to SGA, 56.7% of subjects maintained their nutritional status, 33.3% experienced a deterioration of nutritional status, and 5% had an improvement in nutritional status after four weeks of radiotherapy
  • Change in PG-SGA score was significantly different between those subjects who improved, maintained or deteriorated in status according to SGA (F(3,53)=23.48, P<0.001)
  • Significant correlation between change in PG-SGA score and change in global QOL (R= -0.55, P<0.001) after four weeks of radiotherapy 
  • No associations found between change in PG-SGA and change in QOL according to level of support
  • Significant difference in global QOL scores after four weeks of radiotherapy (t(56)=3.94, P<0.001) and significant linear trend in change in global QOL score for those patients who improved, maintained or declined in nutritional status according to SGA (F(1, 55)=9.5, P=0.003)
  • PG-SGA score at baseline significantly correlated with baseline BMI (R= -0.34, P=0.008) and with percentage weight loss in the previous six months (R=0.53, P<0.001)
  • PG-SGA score at baseline significantly predicted 16% of the variation in global QOL four weeks after commencing radiotherapy (F(1, 55)=4.9, P=0.032)
  • Significant correlation between PG-SGA score and global QOL at baseline (R= -0.66, P<0.001) and after four weeks of radiotherapy (R= -0.61, P<0.001)
  • Regression analysis determine that 26% of the variation of change in QOL was explained by change in PG-SGA score (F(1, 55)=11.6, P=0.001).


Deteriorated Nutritional Status Per SGA


Maintained Nutritional Status Per SGA


Improved Nutritional Status Per SGA


P-value, Per SGA
Change in PG-SGA score 9.5±4.2 2.2±3.8 -5.7±3.1 <0.001
Change in global QOL score -18.9±15.4 -6.6±15.6 19.4±29.3 0.003
Change in BMI -0.6±0.9 -0.2±1.4 1.8±1.4 <0.001



Author Conclusion:

The scored PG-SGA is a nutrition assessment tool that enables malnourished ambulatory patients with cancer to be identified. It is suitable for use as an outcome measure in clinical nutrition practice and is associated with QOL in ambulatory patients receiving radiotherapy to head, neck, abdominal or rectal area. Changes in PG-SGA score can be used to predict the direction and magnitude of change in QOL for this population.

Funding Source:
The Wesley Research Institute
Foundation associated with industry:
Reviewer Comments:
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? Yes
  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? Yes
  2.2. Were criteria applied equally to all study groups? Yes
  2.3. Were health, demographics, and other characteristics of subjects described? Yes
  2.4. Were the subjects/patients a representative sample of the relevant population? Yes
3. Were study groups comparable? Yes
  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? N/A
  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? Yes
  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.) N/A
  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? Yes
  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.) No
  5.3. In cohort study or cross-sectional study, were measurements of outcomes and risk factors blinded? N/A
  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? Yes
  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? Yes
  6.3. Was the intensity and duration of the intervention or exposure factor sufficient to produce a meaningful effect? N/A
  6.4. Was the amount of exposure and, if relevant, subject/patient compliance measured? Yes
  6.5. Were co-interventions (e.g., ancillary treatments, other therapies) described? N/A
  6.6. Were extra or unplanned treatments described? N/A
  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? Yes
  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? Yes
  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? Yes
  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)? Yes
  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