UWL: Screening and Assessment Methods (2009)
The purpose of the study was to create an assessment tool (Mini-Nutritional Assessment Short Form; MNA-SF) that preserves diagnostic accuracy while minimizing the time and training needed for administration and is therefore brief enough for widespread screening.
Not applicable
Not applicable
Recruitment
- Used three populations to develop and test the MNA-SF
- Individuals from the database from the Toulouse-91, the original French population on whom the Mini-Nutritional Assessment (MNA) was developed
- Individuals from a population in Mataro, Spain that had completed the full MNA
- Individuals from a population in Albuquerque, New Mexico that were participants in the New Mexico Aging Process Study.
Design
- The original MNA forms were completed during the three initial studies (described elsewhere) which examined these populations
- The MNA-SF was developed from the database of information for the French participants
- The MNA-SF was subsequently tested using the databases of information from the Spanish and New Mexico participants.
Blinding used
- France
- During the initial study, physicians conducting the assessment of clinical nutrition status did not know the MNA score results for those participants
- No other blinding is reported.
Intervention
- Developed MNA-SF questions utilizing data from French participants
- MNA-SF subsequently tested on Spanish and New Mexico participants.
Statistical Analysis
- Pearson correlations were examined between each item and the MNA total score
- MNA inter-item correlations
- Item analysis procedures to examine internal consistency for all MNA items
- Sensitivity for each item and for the final MNA-SF
- Compared against MNA, physician-judged clinical nutritional status and low serum albumin
- Specificity for each item and for the final MNA-SF
- Compared against MNA, physician-judged clinical nutritional status and low serum albumin
- Diagnostic accuracy for each item and for the final MNA-SF
- Compared against MNA, physician-judged clinical nutritional status and low serum albumin
- Threshold values for MNA-SF were chosen using receiver-operating curves (ROCs) of diagnostic accuracy
- Validation of MNA-SF
- Stepwise discriminant analysis on all 18 items from MNA using 50% random sample of total participants and cross-validating with remaining 50% of participants.
Timing of Measurements
- The timing of the initial data collection for the MNA forms is not described
- The MNA-SF questions were determined and tested using the database information from previously conducted studies.
Dependent Variables
Mini-Nutritional Assessment Short Form (MNA-SF)
Independent Variables
- Independent physician rating of clinical nutritional status (France)
- Mini-Nutritional Assessment (MNA; 18-item; Spain and New Mexico).
Control Variables
None
Initial N
France | Spain | New Mexico | Combined | |
Hospitalized or sub-acute convalescent unit geriatric patients | 105 | 114 | 0 | 219 |
Long-term care or nursing home | 0 | 89 | 1 | 90 |
Independent community-dwelling individuals | 50 | 199 | 346 | 595 |
Total N | 155 | 402 | 347 | 904 |
Attrition (final N)
- Participants with complete MNA
- France 151
- Spain 400
- New Mexico 330
- Total 881.
Age
- Mean age
- France 78.3 years
- Spain 75.8 years
- New Mexico 76.8 years.
Ethnicity
Not provided
Other relevant demographics
France | Spain | New Mexico | Combined | |
Percentage (%) | ||||
Female |
66 | 61 | 60 | 61.4 |
Male |
34 | 39 | 40 | 38.6 |
Albumin (mg/dL), Mean (SD) | 3.30 (0.70) | 3.76 (0.67) | 4.09 (0.31) | 3.83 (0.61) |
Below 3.0 (%) |
34.8 | 11.2 | 0.3 | 11.0 |
3.0 to 3.5 (%) |
21.3 | 26.8 | 2.0 | 12.5 |
Above 3.5 (%) |
43.9 | 62.0 | 97.7 | 76.4 |
Mean MNA score (SD) | 19.9 (6.9) | 23.3 (5.0) | 25.7 (2.4) | 23.6 (5.0) |
Normal (≥24) (percentage) |
35.1 | 58.8 | 81.5 | 63.2 |
At Risk (17-23.5) (percentage) |
28.5 | 30.3 | 18.2 | 25.5 |
Undernourished (less than 17) (percentage) |
36.4 | 11.0 | 0.3 | 11.2 |
France
- 56% had a Folstein mini-mental state of less than 24 out of 30
- 43% had a Katz Activities of Daily living score less than four out of six
- 49% reported anorexia
- 43% were taking more than three medications.
Anthropometrics
- BMI (mean (SD))
- France 22.3 (4.4)
- Spain 27.3 (5.0 )
- New Mexico 25.2 (3.7).
Location
- France
- Mataró, Spain
- Albuquerque, New Mexico.
MNA Items: Correlation with total MNA score and diagnostic characteristics relative to clinical nutritional status
(n=142 from French participants)
Item | Content | Pearson r with MNA total score | Sensitivity | Specificity | Accuracy | Χ2 |
1 | BMI less than 23 | 0.698 | 0.795 | 0.774 | 0.787 | 53.06 |
2 | Mid-arm circumference ≤22 | 0.317 | 0.125 | 1.000 | 0.454 | 7.18 |
3 | Calf circumference less than 31 | 0.598 | 0.614 | 0.960 | 0.745 | 45.82 |
4 | Recent weight loss greater than 1kg | 0.750 | 0.875 | 0.774 | 0.837 | 62.69 |
5 | Lives in nursing home or hospital | 0.121 | 0.483 | 0.604 | 0.528 | 1.04 |
6 | Prescription medications greater than three per day | 0.307 | 0.584 | 0.755 | 0.648 | 15.38 |
7 | Acute illness or stress | 0.781 | 0.910 | 0.906 | 0.909 | 92.56 |
8 | Housebound | 0.799 | 0.775 | 0.925 | 0.831 | 67.79 |
9 | Dementia or depression | 0.700 | 0.652 | 0.943 | 0.761 | 48.03 |
10 | Pressure sore or ulcers | 0.556 | 0.416 | 0.981 | 0.627 | 26.69 |
11 | Less than three meals per day | 0.288 | 0.122 | 0.962 | 0.489 | 7.35 |
12 | Less than three protein sources per day | 0.333 | 0.588 | 0.736 | 0.645 | 15.17 |
13 | Less than two servings of vegetables or fruit per day | 0.279 | 0.165 | 1.000 | 0.486 | 9.72 |
14 | Appetite loss or eating difficulty | 0.743 | 0.775 | 0.981 | 0.852 | 76.05 |
15 | ≤ five cups fluid per day | 0.454 | 0.565 | 0.792 | 0.652 | 17.48 |
16 | Self-fed with difficulty or unable | 0.691 | 0.472 | 0.981 | 0.690 | 32.46 |
17 | Moderate or major malnutrition | 0.731 | 0.652 | 0.962 | 0.768 | 51.33 |
18 | Health worse or don't know | 0.515 | 0.618 | 0.887 | 0.718 | 35.92 |
MNA 18-item | 0.989 | 0.943 | 0.972 | 125.41 | ||
MNA-SF 6-item | 0.969 | 0.987 | 0.943 | 0.965 | 121.38 |
Other Findings
- Six items with the highest sensitivity and overall accuracy were selected for the initial MNA-SF
- Successively deleting items in the item analysis yielded the same six-item scale
- Internal consistency MNA-SF (alpha coefficient) 0.843
- Internal consistency full MNA (alpha coefficient) 0.865.
French Population (development of MNA-SF)
- MNA-SF compared to full MNA
- Sensitivity 97.9%
- Specificity 100%
- Diagnostic accuracy 98.7%
- Comparison to clinical nutrition assessment for detecting persons who are undernourished
- MNA-SF diagnostic accuracy 97.2%
- Full MNA diagnostic accuracy 96.5%
- Comparison to albumin
- MNA-SF Pearson correlation, r=0.679
- Full MNA Pearson correlation, r=0.699
- MNA-SF diagnostic accuracy 98.7%.
Total Population (testing of MNA-SF)
- MNA-SF vs. MNA
- Pearson correlation, r=0.945 (P<0.0001)
- Using greater than 11 as cutpoint for normal nutrition on MNA-SF, MNA-SF ability to predict malnutrition on full MNA:
- MNA-SF sensitivity 97.9%
- MNA-SF specificity 100%
- MNA-SF diagnostic accuracy 98.7%.
Discriminant Analysis
- Performed in two 50% random samples of the total population
- Five of six of the MNA-SF items were selected among the first seven to enter the stepwise analysis (steps one, two, four, six and seven)
- All six MNA-SF items were significant at P<0.0001
- Performed in the Spanish and New Mexico populations
- Five of six of the MNA-SF items were selected among the first seven to enter the stepwise analysis (steps one, two, three, five and six)
- All six MNA-SF items were significant at P<0.0001
- 87.9% of cases were correctly classified according to their full MNA score category.
- The MNA-SF has six questions and can be administered in approximately three minutes
- The MNA-SF has high diagnostic accuracy relative to clinical nutritional status, high correlation with the full MNA
- The MNA-SF is as good as the MNA in predicting serum albumin.
Government: | U.S. Department of Veterans Affairs | |
Industry: |
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This is a well designed study using a large population to develop and test the MNA-SF.
Quality Criteria Checklist: Primary Research
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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? | No | |
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? | ??? | |
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) | Yes | |
3.2. | Were distribution of disease status, prognostic factors, and other factors (e.g., demographics) similar across study groups at baseline? | Yes | |
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.) | ??? | |
3.6. | If diagnostic test, was there an independent blind comparison with an appropriate reference standard (e.g., "gold standard")? | Yes | |
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? | Yes | |
5. | Was blinding used to prevent introduction of bias? | Yes | |
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? | Yes | |
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? | Yes | |
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? | 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? | 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? | No | |
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? | 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 | |