MNT: Gastrointestinal Disorders (2015
Citation:Lee AR, Ng DL, Dave E, Ciaccio EJ, Green PHR. 2009. The effect of substituting alternative grains in the diet on the nutritional profile of the gluten-free diet. J Hum Nutr Diet, 22, pp. 359-363. doi: 10.1111/j.1365-277X.2009.00970.x PubMed ID: 19519750
Retrospective Cohort Study
B - Click here for explanation of classification scheme.
To determine whether the nutritional profile of a gluten-free diet could be improved through the use of alternative grains.
Not specified by authors.
Not specified by authors.
Description of Study Protocol:
Recruitment50 patients of the Celiac Disease Center were randomly selected to participate in the study.
- In this retrospective review of diet history, 50 randomly selected patients from the Celiac Disease Center at Columbia University provided the dietitian with a three-day food diary of their usual intakes
- The grain/starch choices were recorded by grain category, number of servings of grains and meal at which grain was consumed
- Intake patterns from the 50 food diaries were averaged together to create one average intake pattern
- The alternative gluten-free diet pattern was created by substituting only the grain or starch portion of the standard menu pattern with alternative gluten-free grains or grain products. This alternative pattern used oats at breakfast, high-fiber brown rice bread at lunch and quinoa as a starch side dish at dinner. The grain choices were then analyzed for nutrient content comparing both the standard and alternative diet pattern.
ANOVA and paired T-tests were used to identify statistical significance between the standard and alternative gluten-free diet patterns.
Data Collection Summary:
- Timing of measurements: Three-day food diaries were retrospectively reviewed by the dietitian
- Dependent variables: Three-day food diaries self-reported by patients
- Independent variables: Substituting the grain or starch portion of the average meal pattern with alternative gluten-free grains (oats at breakfast, high-fiber brown rice bread at lunch and quinoa at dinner)
- Control variables: Only the grain choices were analyzed for the nutrient content comparing both the standard and alternative diet pattern.
Description of Actual Data Sample:
- Initial N: 50 patients
- Attrition (final N): None specified by authors
- Age: Not specified
- Ethnicity: Not specified
- Other relevant demographics: Not specified
- Anthropometrics: Not specified
- Location: Celiac Disease Center, Columbia University, New York.
Summary of Results:
- The standard gluten-free diet did not meet the USDA's recommended six to 11 servings of grains per day
- Standard gluten-free diet grains consisted of 44% rice (predominately white), 8% potato, 5% oats, 3% corn, 1% Buckwheat and 1% quinoa; 38% consumed no grains; 55% of snacks comprised commmercially prepared snacks (chips, pretzels, GF cookie, donuts and cake)
- The alternative diet pattern provided an improved nutrient profile compared to the standard gluten-free diet (P=0.0002)
- The change in dietary grains significantly increased protein (20.6g vs. 11g), iron (18.4mg vs. 1.4mg), calcium (182mg vs. 0.0mg) and fiber (12.7g vs. 5.0g).
- Changing the grains in a gluten-free diet has the potential to improve the nutritional profile of the diet for individuals with celiac disease
- Patients and their dietary counselors require education on alternative sources to diversify the standard gluten-free diet.
|University/Hospital:||Celiac Disease Center, School of Medicine, Columbia University|
- Although the authors stated that selected nutrient levels significantly increased with changing the dietary grains (i.e., iron, calcium, fiber and protein), they did not provide a P-value for each nutrient. The only P-value provided was for an overall improved nutrient profile.
- The authors do state limitations of the study: These include a population bias because the diet history records were provided by individuals attending a large celiac disease center, a small sample size (N=50), limited nutritional analysis and the potential inaccuracies of reported food intakes.
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?||???|
|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?||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?||???|
|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?||Yes|
|6.1.||In RCT or other intervention trial, were protocols described for all regimens studied?||Yes|
|6.2.||In observational study, were interventions, study settings, and clinicians/provider described?||N/A|
|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?||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)?||N/A|
|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|