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Adult Weight Management

AWM: Eating Frequency and Patterns (2013)

Citation:

Andersson I, Rossner S. Meal patterns in obese and normal weight men:  The Gustaf study. Eur J Clin Nutr 1996;50:639-46.

 
Study Design:
cohort
Class:
B - Click here for explanation of classification scheme.
Quality Rating:
Neutral NEUTRAL: See Quality Criteria Checklist below.
Research Purpose:
To compare the recorded meal patterns between obese and normal weight men.
Inclusion Criteria:
Men between the ages of 20 and 60 who had no known disease or disturbance expected to interfere with the study.
Exclusion Criteria:
For normal weight group, men with a BMI > 26.0  were excluded.
Description of Study Protocol:

Recruitment Obese men from a waiting list and men directly approaching an obesity unit were invited to participate.  Normal weight men were randomly selected from the Stockholm County Census Bureau and were sent an invitation to participate together with a questionnaire about present height and weight.

Design A dietary survey with 12 24-hour dietary recalls was conducted over three months.  All days of the week were represented in the recalls. The contribution of intake types to the reported daily energy intake was studied, as well as the circadian distribution of energy intake and the reported number of intakes. Analyses were conducted in 2 groups: A was all men who finished the study (86 obese, 61 normal weight), B was all men who finished the study and reported plausible intakes (23 obese, 44 normal weight).

Blinding used (if applicable) NA

Intervention (if applicable) NA

Statistical Analysis The Mann-Whitney Two Sample Test was used to compare the 2 groups.  The critical P was set at 0.01.

Data Collection Summary:

Timing of Measurements 12 times across 3 months (which included all 7 days of the week)

Dependent Variables weight status

Independent Variables

1). Types of intake

  • cooked meal
  • sandwich meal
  •  snacks
  • breakfast-like meal
  • 'cocktail' meal
  • beverage
  • fruit
  • 'extreme' meals
  • other intakes

2). Circadian distribution of energy intake (military time)

  • 04.00-09.59
  • 10.00-15.59
  • 16.00-21.59
  • 22.00-03.59

3). Reported number of intakes

Control Variables Although several other variables were measured (marital status, work status, physical activity at work and leisure, and smoking), they were not used in the analyses.

Description of Actual Data Sample:

Initial N: Attrition (final N): 86 of 116 (74%) invited obese men finished (10 did not answer request, 17 declined to participate, and 3 men did not complete the study).  61 of 190 (32%) invited normal weight men completed the study (29 were excluded due to a BMI > 26.0, 48 did not answer the request, 50 did not wish to participate, and 2 had serious diseases).

Age: obese men = mean of 43 years (range = 25-60), normal weight men = mean age of 39 (range = 23-60)

Ethnicity: Swedish

Other relevant demographics: NA

Anthropometrics obese men had a mean BMI of 37.7 (range = 29.9-48.9), normal weight men had a mean BMI of 23.0 (range = 17.6-25.9)

Location: Obesity unit in Stockholm

Summary of Results:

For the A analyses (all men who completed the study; 86 obese, 61 normal weight):

  • There were no significant differences for type of intake between the groups.
  • 22 extreme meals were reported by obese men and 2 for normal weight men - but difference was not tested statistically because of low observations.
  • Obese men reported greater servings from fruits (0.5 MJ vs 0.3 MJ (119.42 vs. 71.65 kcals), P< 0.01).
  • Obese men reported a median of 5.3 intakes/day vs 5.6 in the normal weight men (P=0.02)
  • Obese men reported intakes from breakfast-like meals (mean of 0.3 vs. 0.5.day, P<0.001) and from cocktail meals (mean of 0.2 vs 0.3/day, P<0.001) to a lesser extent than the normal weight men.

For the B analyses (only men who reported plausible intakes; 23 obese, 44 normal weight):

  • Obese men reported greater servings from sandwich meals (2.7 MJ vs. 1.9 MJ (644.88 vs. 453.81), P<0.001); snacks (1.7 MJ vs. 1.1 MJ (406.04 vs. 262.73 kcals), P<0.01)l and breakfast-like meals (3.3 MJ vs. 2.4 MJ (788.19 vs. 573.23 kcals), P<0.001).
  • Obese men reported a higher percentage of energy intake at night (22.00-03.59) than normal weight men (8% vs. 4%, P<0.01).

Other findings:

A larger number of obese men reported implausbily low dietary intakes (73% vs. 28%).

Author Conclusion:
There were no major differences in intake types and time trends between the obese and normal weight men.  The obese men underreported to a much higher degree than the normal weight men, 73% vs. 28%.  Eliminating these obvious under-reporters did not change the patterns in any fundamental way.
Funding Source:
Reviewer Comments:

This report does not add to our knowledge of intake differences between obese and normal weight men.  There were few significant differences and those found were small.  Although they do report a fairly large difference in total intake between the two groups (when only the plausible reporters were included obese men had a median intake of 14.5 MJ vs 11.8 MJ (3463.27 vs. 2818.38 kcals) for normal weight men, P<0.001), this was not the focus of their paper. 

Other concerns include the large number of statistical tests done (>50) and the fact that the obese men were seeking treatment and may have been modifying their intake during the time of the study.

This study did consider how under-reporting of intake might have affected their results.  While this did not have an effect on their results, it strengthens confidence in the design.

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) N/A
  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) N/A
  2. Did the authors study an outcome (dependent variable) or topic that the patients/clients/population group would care about? 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
  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) N/A
  4. Is the intervention or procedure feasible? (NA for some epidemiological studies) N/A
 
Validity Questions
  1. Was the research question clearly stated? 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
  1.1. 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
  1.2. Was (were) the outcome(s) [dependent variable(s)] clearly indicated? Yes
  1.3. Were the target population and setting specified? Yes
  1.3. Were the target population and setting specified? Yes
  2. Was the selection of study subjects/patients free from bias? No
2. Was the selection of study subjects/patients free from bias? No
  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? 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? Yes
  2.2. Were criteria applied equally to all study groups? Yes
  2.2. Were criteria applied equally to all study groups? Yes
  2.3. Were health, demographics, and other characteristics of subjects described? 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? ???
  2.4. Were the subjects/patients a representative sample of the relevant population? ???
  3. Were study groups comparable? Yes
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) 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
  3.2. 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
  3.3. 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? ???
  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? ???
  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.) ???
  3.5. 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")? 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. Was method of handling withdrawals described? Yes
  4.1. Were follow-up methods described and the same for all groups? 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
  4.2. 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
  4.3. Were all enrolled subjects/patients (in the original sample) accounted for? Yes
  4.4. Were reasons for withdrawals similar across groups? No
  4.4. Were reasons for withdrawals similar across groups? No
  4.5. If diagnostic test, was decision to perform reference test not dependent on results of test under study? 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. 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
  5.1. 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
  5.2. 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
  5.3. 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
  5.4. 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
  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. 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
  6.1. 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
  6.2. 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
  6.3. 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
  6.4. 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
  6.5. Were co-interventions (e.g., ancillary treatments, other therapies) described? N/A
  6.6. Were extra or unplanned treatments 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
  6.7. 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
  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. 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
  7.1. 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
  7.2. 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
  7.3. 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
  7.4. 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? No
  7.5. Was the measurement of effect at an appropriate level of precision? No
  7.6. Were other factors accounted for (measured) that could affect outcomes? No
  7.6. Were other factors accounted for (measured) that could affect outcomes? No
  7.7. Were the measurements conducted consistently across groups? 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? ???
8. Was the statistical analysis appropriate for the study design and type of outcome indicators? ???
  8.1. Were statistical analyses adequately described and the results reported appropriately? 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
  8.2. 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
  8.3. 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
  8.4. 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
  8.5. 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
  8.6. 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
  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. Are conclusions supported by results with biases and limitations taken into consideration? Yes
  9.1. Is there a discussion of findings? Yes
  9.1. Is there a discussion of findings? Yes
  9.2. Are biases and study limitations identified and discussed? No
  9.2. Are biases and study limitations identified and discussed? No
  10. Is bias due to study's funding or sponsorship unlikely? Yes
10. Is bias due to study's funding or sponsorship unlikely? Yes
  10.1. Were sources of funding and investigators' affiliations described? Yes
  10.1. Were sources of funding and investigators' affiliations described? Yes
  10.2. Was the study free from apparent conflict of interest? Yes
  10.2. Was the study free from apparent conflict of interest? Yes