The EAL is seeking RDNs and NDTRs who work with patients, clients, or the public to treat children and adolescents living with type 1 diabetes, for participation in a usability test and focus group. Interested participants should email a professional resume to by July 15, 2024.

MIP: Weight Loss Surgery (2018)

Author and Year:
Burke A, Bennett W et al, 2010
PubMed ID:
Article Title:
Reduced incidence of gestational diabetes with bariatric surgery.
Burke A, Bennett W, Jamshidi R, Gilson M, Clark J, Segal J, Shore A, Magnuson T, Dominici F, Wu A, Makary M
Journal of the American College of Surgeons
Year of publication:
Page numbers:
Study Design:
Retrospective Cohort Study
Risk of Bias Assessment Rating:
Inclusion Criteria:
Inclusion in the Blue Cross Blue Shield dataset used for this analysis required at least one of the following criteria at any point during 2002 to 2006: Completed health risk assessment or other survey capturing member height and weight Claim for an obesity diagnosis Claim for bariatric surgery Prescription claim for a weight reduction medication Diagnosis code of hyperlipidemia, type 2 diabetes, sleep apnea, gallbladder disease, or metabolic syndrome. For inclusion in the cohort, we required at least six months of continuous insurance coverage before the delivery date.
Exclusion Criteria:
Women with pre-existing diabetes, defined either as having International Classification of Disease-9 (ICD-9) codes associated with diabetes more than 20 weeks before delivery (648.0x, 250.xx, 648.8x, 775.0x) or a prescription claim for a diabetes medication in this time period. Gestational diabetes (648.0x) was one of the exclusion codes if it was reported more than 20 weeks before delivery, to avoid mis-classification of pre-existing diabetes as GDM. We did not exclude women with GDM in a previous pregnancy or women with a prescription claim for only metformin if there was a corresponding ICD-9 code for polycystic ovarian syndrome (PCOS) and no code for a diabetes diagnosis. We excluded all pregnancies with multiple fetuses (an independent risk factor for GDM and other outcomes of interest 23), women who had 31 days or fewer between delivery and bariatric surgery or vice versa (presumed to be a coding error) and women younger than 18 years of age on day of delivery.
Research Purpose:
Although the impact of the procedure (bariatric surgery) on weight loss and potential public health benefits have been described, little is known about its implications for maternal-fetal outcomes. We hypothesized that bariatric surgery may prevent GDM in obese women and reduce the incidence of associated pregnancy complications.
Blinding efforts:
None described.
Study Location:
Rockville, MD (Data from TN, PA, MI, NC, IA, SD, and HI)
Source(s) of Funding:
Industry, Private donor
Please specify names of funders:
Data and database development support were provided by the BCBS Association, BCBS of Tennessee, BCBS of Hawaii, BCBS of Michigan, BCBS of North Carolina, Highmark, Inc. (of Pennsylvania), Independence Blue Cross (of Pennsylvania), Wellmark BCBS of Iowa and Wellmark BCBS of South Dakota. Additional funding was provided by Mr. and Mrs. Chad and Nissa Richison.
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? 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
  2.3. Were health, demographics, and other characteristics of subjects described? Yes
  2.4. Were the subjects/patients a representative sample of the relevant population? 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
  3.2. Were distribution of disease status, prognostic factors, and other factors (e.g., demographics) similar across study groups at baseline? No
  3.3. Were concurrent controls or comparisons used? (Concurrent preferred over historical control or comparison groups.) Yes
  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? Yes
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
5. Was blinding used to prevent introduction of bias? No
  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
6. Were intervention/therapeutic regimens/exposure factor or procedure and any comparison(s) described in detail? Were interveningfactors 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? Yes
  6.4. Was the amount of exposure and, if relevant, subject/patient compliance measured? Yes
  6.5. Were co-interventions (e.g., ancillary treatments, other therapies) described? Yes
  6.7. Was the information for 6.4, 6.5, and 6.6 assessed the same way for all groups? 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
  7.2. 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? ???
  7.6. Were other factors accounted for (measured) that could affect outcomes? 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? 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? 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