AWM: Nutrition Education (2006)
Marietta AB, Welshimer KJ, Anderson SL. Knowledge, attitudes, and behaviors of college students regarding the 1990 Nutrition Labeling Education Act food labels. J Am Diet Assoc 1999; 99: 445-449.PubMed ID: 10207397
Students enrolled in a basic life science course that fulfilled a general university requirement.
Blinding used (if applicable)
Intervention (if applicable)
Provided with survey and given 20 minutes to complete.
Frequencies, percentages, and means were calculated to analyze students' knowledge, attitudes and behaviors regarding food labels. The Student t test was used to compare parametric scores of behaviors relating to general usage of the label between men and women. The chi-square analysis was used to compare nonparametric nutrient item selections with respect to sex and previous label-reading educational experience of participants. Pearson product moment correlation coefficients were calculated to examine associations between age, sex and previous educational experience with label reading and knowledge, attitudes or behaviors. Multiple regression analysis was used to further evaluate the independent contributions of knowledge, attitude, sex, age and previous educational experience with food labels to behavior. An F statistic based on the regression equation was calculated to determine significance at the 0.05 level.
Timing of Measurements
39-item questionnaire developed for the study, designed to measure knowledge, attitudes, and behaviors of participants. A 5-member expoert panel evaluated the instrument for content validity and clarity. Instrument was pilot tested and revised. Cronbach alpha = 0.8 for reliability. Flesch-Kincaid reading grade level of 8.2.
- Knowledge questions assessed students' knowledge of basic facts needed for effective consumer use of the NLEA label and their ability to obtain specific information from labels
- Attitude questions assessed students' attitudes toward the food labels in areas of truthfulness and accuracy
- Self-reported behaviors were divided into 2 types: those related to general use of the label and those related to specific items appearing on the label
- Demographic information
Initial N: 208 undergraduates
Attrition (final N): 208 undergraduates, 141 women, 67 men
Age: Mean age 21.7 +/- 5.6, range 17 - 53 years
Ethnicity: 97.1% born in the US
Other relevant demographics: 107 students reported prior exposure to some form of label-reading education.
Anthropometrics (e.g., were groups same or different on important measures)
Location: Southeast Missouri State University
|Knowledge and behavior (general label usage)||0.87||0.0001|
|Attitude and behavior (general label usage)||0.27||0.0001|
|Attitude and behavior (item seeking)||0.23||<0.001|
Knowledge and attitude
Knowledge and behavior (item seeking)
Students' mean knowledge was 48.4%. Knowledge score was positively correlated with attitudes toward labels (r = 0.14, P = 0.04) and use of labels (r = 0.87, P = 0.0001).
Previous education in reading labels was associated with higher knowledge scores (P = 0.04).
95% of participants perceived the label to be useful, but many distrusted nutrition claims.
70.2% looked at the Nutrition Facts label when purchasing a product for the first time.
72.1% also responded that they would purchase, at least sometimes, a product with a health claim on the label rather than a similar product with no health claim.
43.8% used the label at least sometimes to help fit a food into their daily diet. Women were more likely than men to look at the label more often (P < 0.001) and to use the label to help fit food into their daily diet (P < 0.001).
Women were significantly more likely than men to look for information about total calories (P < 0.001), total fat (P < 0.001), and saturated fat (P < 0.01). Men were significantly more likely than women to look for information about protein (P < 0.001) and vitamin A (P < 0.001).
The single best predictor of general label use was a positive attitude toward labels (r2 = 0.08, P < 0.001), followed by being a woman (r2 = 0.04, P < 0.01).
|University/Hospital:||Southeast Missouri State University, Southern Illinois University|
Quality Criteria Checklist: Primary Research
|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|
|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?||???|
|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?||N/A|
|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?||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?||N/A|
|4.1.||Were follow-up methods described and the same for all groups?||N/A|
|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%.)||N/A|
|4.3.||Were all enrolled subjects/patients (in the original sample) accounted for?||N/A|
|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?||???|
|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?||N/A|
|7.4.||Were the observations and measurements based on standard, valid, and reliable data collection instruments/tests/procedures?||???|
|7.5.||Was the measurement of effect at an appropriate level of precision?||N/A|
|7.6.||Were other factors accounted for (measured) that could affect outcomes?||N/A|
|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?||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|