UWL: Screening and Assessment Methods (2009)

Study Design:
- Click here for explanation of classification scheme.
Quality Rating:
Research Purpose:

To investigate the association of a recently-devised quantitative Subjective Global Assessment method and an invented, modified quantitative Subjective Global Assessment method scoring system with conventional Subjective Global Assessment.

Inclusion Criteria:
  • Adults admitted to the wards of a university referral center between March 2001 and February 2002
  • All were subjects of a previous investigation that focused on the prevalence of malnutrition in the center and the effectiveness of different malnutritional screening tools.
Exclusion Criteria:
  • Pregnancy
  • Psychiatric conditions
  • Admission to intensive care units.
Description of Study Protocol:


The setting was a university referral center with 250 beds and all subjects were adults admitted to the wards. Between March 2001 and February 2002, 2,211 patients gave their written informed consent to participate.


Cross-sectional study.

Statistical Analysis

  • In the invented modified quantitative Subjective Global Assessment (SGA) system, the items were entered into the logistic regression model and weighted scores were calculated according to the weighted effect of the SGA items
  • Chi-square analysis was used to compare categorical variables and one-way ANOVA was used to analyze continuous variables among SGA categories
  • Receiver operating characteristics (ROC) curves were calculated for quantitative SGA and modified quantitative SGA to compare the correlation of these methods in predicting SGA outcome
  • Cut-off points for quantitative SGA and modified quantitative SGA were identified based on ROC curve analysis and sensitivity and specificity calculations.
Data Collection Summary:

Timing of Measurements

  • All enrolled subjects underwent an initial assessment within 48 hours of admission, however not all patients gave permission for their laboratory data to be used
  • It was not possible to collect all the study data in some cases.

Dependent Variables


Independent Variables

  • Conventional Subjective Global Assessment (SGA)
  • Quantitative SGA obtained by assigning one point for each increasing severity level
  • Anthropometric measurements
    • Weight, measured with a King scale
    • Height, measured on a wall-mounted scale
    • BMI
    • Triceps skinfold, measured with calipers
    • Midarm circumference
    • Midarm muscle circumference.
  • Laboratory testing: Blood samples were analyzed for hemoglobin, hematocrit, white blood cell count, lymphocyte count and serum levels of albumin, prealbumin, total protein and total cholesterol.

Control Variables

Patient demographics.

Description of Actual Data Sample:
  • Initial N: 2,197 patients with sufficient data to be included in the analysis
  • Attrition (final N): 2,197 patients, 1,073 men (48.8%)
  • Age: Mean age, 54.4±14.8 years
  • Ethnicity: Not mentioned
  • Location: Ankara, Turkey.
Summary of Results:


SGA: Well Nourished (N=1,955)

SGA: Moderately Malnourished (N=215) SGA: Severely Malnourished (N=27)


Sex, Male

Sex, Female

Age (Years)





Surgery Specialty
Medicine Specialty
Primary Educational Status
Junior High or Higher Educational Status
Urgent Type of Admission
Elective Type of Admission
Malignancy, No
Malignancy, Yes
Triceps Skinfold
<10th Percentile
Triceps Skinfold
>10th Percentile
Mid-Arm Circumference
<10th Percentile
Mid-Arm Circumference
>10th Percentile
Mid-Arm Muscle Circumference
<10th Percentile
Mid-Arm Muscle Circumference
>10th Percentile
Hemoglobin (g/dL)
White Cell Count per mm3
Lymphocyte Percentage
Albumin (g/dL)
Total Cholesterol (mg/dL)
Deaths at 6 Months After Discharge

Other Findings

  • 89% of patients were classified as well-nourished according to conventional SGA; 9.8% were classified as moderately malnourished; 27 patients (1.2%) were classified as severely malnourished
  • When patients were grouped according to binary SGA outcome (well nourished vs. malnourished), receiver operating characteristics curve areas for the quantitative SGA and modified quantitative SGA scores were 0.897 (95% confidence interval, 0.875 to 0.919) and 0.952 (95% confidence interval, 0.939 to 0.964), respectively
  • The cutoff points for quantitative SGA and modified quantitative SGA were identified as 10 and 18, respectively
  • Although the sensitivity of these systems in identifying malnutrition were similar (90.0% and 90.9%, respectively), the specificity of modified quantitative SGA was greater than that of quantitative SGA (85.6% vs. 67.0%).


Author Conclusion:
  • The findings suggest that modified quantitative SGA outperforms quantitative SGA in identifying malnutrition according to SGA
  • Future nutrition scoring studies need to take into account the weighted effects of items on outcome.
Funding Source:
University/Hospital: Baskent University
Reviewer Comments:

Large sample size.

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? N/A
  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? N/A
  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? 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? N/A
  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? 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? N/A
  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? N/A
  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? N/A
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? N/A
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? No
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