CD: Wheat Starch (2006)

Citation:

Thompson T. Questionable foods and the gluten-free diet: Survey of current recommendations. J Am Diet Assoc 2000; 100(4):463-465.

 
Study Design:
Cross-sectional study
Class:
D - Click here for explanation of classification scheme.
Quality Rating:
Neutral NEUTRAL: See Quality Criteria Checklist below.
Research Purpose:
  • To ascertain recommendations being made to persons with CD on the use of certain "questionable" foods in a GFD.
Inclusion Criteria:
  • None defined.
Exclusion Criteria:
  • None defined.
Description of Study Protocol:

Recruitment

  • Questionnaire mailed to five US celiac organizations, 58 foreign celiac organizations, and 42 US MDs who treat CD patients.

Design

  • Cross-sectional study, survey.

Intervention

  • Survey participants asked about acceptability of foods in a GFD and to provide their reasoning for the following foods: Oats, millet, sorghum, buckwheat, quinoa, amaranth, wheat starch, distilled alcohol made from wheat, rye or barley mash, distilled white vinegar, foods containing distilled white vinegar, malt made from barley, or malt extract or malt flavoring made from barley.

Statistical Analysis

  • Checked responses were tabulated and results presented as actual numbers and percentages. Data were analyzed for all respondents and by respondent category.
Data Collection Summary:

 

 

Description of Actual Data Sample:

  • Initial N: 105 questionnaires mailed to five US celiac organizations, 58 foreign celiac organizations and 42 US MDs who treat CD patients.
  • Attrition (final N): 99 questionnaires were deliverable, 37 completed and used (37% response rate).

Other relevant demographics

  • Four out of five US celiac organizations responded
  • 18 out of 58 foreign celiac organizations responded
  • 12 US MDs responded
  • Three others (RD/Nutritionist) responded.
Summary of Results:

Acceptability of selected foods by respondents

Food Item

All Respondents

US Celiac Orgs

Foreign Orgs

US MDs

Others

Amaranth

84%

50%

94%

100%

33%

Sorghum

84%

75%

87%

90%

50%

Millet

79%

50%

83%

100%

33%

Quinoa

77%

50%

87%

89%

33%

Buckwheat

74%

75%

94%

55%

33%

Distilled white vinegar

73%

25%

100%

70%

0%

Foods with distilled white vinegar

72%

25%

100%

70%

0%

Distilled alcohol made from wheat, rye, or barley mash

44%

25%

53%

50%

0%

Wheat starch

38%

0%

67%

20%

0%

Foods containing malt extract or flavoring made from barley

21%

0%

40%

8%

0%

Oats

15%

0%

6%

40%

0%

Foods containing malt made from barley

9%

0%

13%

8%

0%

Other Findings

  • Concerns about oats: Possible toxicity due to gluten contamination, insufficient research in general, inadequate length of follow-up in studies, lack of information about amounts of oats that may be safely consumed
  • Concerns about wheat starch: Inability to find a pure source, gliadin content, lack of US regulations for wheat starch. Many respondents from foreign celiac organizations indicated that only specific gluten-free wheat starch complying with Codex standard was allowed.
Author Conclusion:
  • There is a need for consensus among celiac organizations in the US on foods for inclusion in a GFD. All respondents from US celiac organizations considered oats, wheat starch, malt and malt flavoring to be unacceptable in a GFD. In contrast, millet, sorghum, buckwheat, quinoa, amaranth, distilled alcohol, distilled white vinegar and foods containing distilled white vinegar were acceptable to some and unacceptable to others. The celiac organizations in the US provide valuable information to persons with CD as well as to MDs and RDs. To prevent confusion, these organizations should issue one set of dietary recommendations for people who consume a GFD.
Funding Source:
Other: not reported
Reviewer Comments:
  • Selection method for 105 participants not defined. With response rate of 37%, similarities and differences regarding respondents and non-respondents not addressed.
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? ???
  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? ???
  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%.) ???
  4.3. Were all enrolled subjects/patients (in the original sample) accounted for? N/A
  4.4. Were reasons for withdrawals similar across groups? ???
  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? N/A
  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? N/A
  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? N/A
  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? 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? 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? N/A
  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? N/A
  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