DM: Carbohydrates (2007)
Type I diabetes.
Recruitment: not specified
Design: 4-week run in period, followed by randomized 4-week periods of each of two diets: use of sucrose as sweetener or cyclamate as sweetener
Blinding used (if applicable): not possible, as sweeteners were easily distinguishable
Intervention (if applicable)
- Sucrose period
- sucrose and sucrose-sweetened foods allowed ad libitum
- sucrose-sweetened soft drinks discouraged
- Cyclamate period: sodium cyclamate allowed ad libitum up to a maxium of 11 mg/kg body weight per day
Statistical Analysis
Student's t-test used for paired and unpaired comparison
Timing of Measurements
- glucose readings, daily insulin dose, and intake of carbohydrates recorded every day by patient
Dependent Variables
- blood glucose: subjects performed regular blood glucose self-monitoring, which was "repeatedly" checked out against laboratory techniques.
- body weight, postprandial plasma glucose, HbA1c, fasting serum cholesterol and lipids measure bi-weekly
Independent Variables
- sucrose or cyclamate periods
- patients noted in diary frequency and amount of sucrose intake
- cyclamate tablets and liquids were provided to subjects and intake measured by counting what was left over at the end of the study
- 3-day dietary monitoring period carried out within each of the diet periods
Control Variables
Initial N: 10; 8 women
Attrition (final N):10
Age: 25-43 yrs
Ethnicity: not specified
Other relevant demographics: duration of diabetes -18 years; on insulin infusion therapy for more than one year; mean HbA1c of 7.5%
Anthropometrics : all had a BMI less than 25
Location: Germany
Metabolic control at 4 weeks during each of the three study periods
Variables |
Run-in period |
Cyclamate Period | Sucrose Period | Significance |
Body weight, kg |
67.0±7.6 | 67.6±8.0 |
66.8±7.2 |
NS |
HbA1c |
7.57±0.96 |
7.46±0.75 |
7.48±0.44 |
NS |
total cholesterol, mmol/l |
5.17±1.16 |
5.09±0.80 |
5.43±1.09 |
NS |
HDL, mmol/l | 1.89±0.52 | 1.81±0.57 |
1.86±0.36 |
NS |
Triglycerides, mmol/l | 0.90±0.20 | 0.93±0.20 | 0.95±0.30 | NS |
Random plasma glucose, mmol/l | 6.66±4.79 | 6.60±2.97 | 5.94±2.86 | NS |
Other Findings
- CHO, protein, and fat intake were the same during the three observation periods
- mean sucrose consumption was 24±13 g/day and mean cyclamate consumption was 10.46±8.09g/day
- the frequency of blood glucose self-monitoring was significantly higher during the sucrose period
University/Hospital: | Dusselldorf University |
Inclusion/exclusion criteria and recruitment methods not well described.
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? | ??? | |
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? | Yes | |
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? | 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? | ??? | |
5.1. | In intervention study, were subjects, clinicians/practitioners, and investigators blinded to treatment group, as appropriate? | ??? | |
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.) | ??? | |
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? | ??? | |
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? | No | |
6.4. | Was the amount of exposure and, if relevant, subject/patient compliance measured? | No | |
6.5. | Were co-interventions (e.g., ancillary treatments, other therapies) described? | Yes | |
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? | 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? | ??? | |
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? | N/A | |
7.3. | Was the period of follow-up long enough for important outcome(s) to occur? | No | |
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? | No | |
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)? | No | |
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? | No | |
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 | |