DM: MNT (2007)

Citation:
 
Study Design:
Class:
- Click here for explanation of classification scheme.
Quality Rating:
Research Purpose:
To explore the efficacy of combining care management and interdisciplinary group visits for rural African American patients with diabetes mellitus (DM).
Inclusion Criteria:

In intervention group, patients were informed and asked to participate if:

  • established diagnosis of type 2 diabetes, with one of the following conditions on day of visit:
  • HbA1c greater than 7.0%,
  • blood pressure (BP) greater than 135/85 mm Hg, or
  • physical exam or laboratory evidence of a high risk of end-stage organ disease including diabetic retinopathy, nephropathy, or neuropathy.

In control practice, patient charts were reviewed to identify those with same conditions (glycemic control, BP control, or chart-documented evidence of end-organ damage.)

Exclusion Criteria:
Not specified.
Description of Study Protocol:

Recruitment - Sample taken from 2 primary care practices in adjacent rural counties, both hospital owned at time of study, in existence for approximately 30 years, each in a community of approximately 3500 people, with a total active patient population of 2000 - 3000. One practice designated as a federal health professions shortage area. Both practices represent rural fee-for-service practices that provide primary care for predominately African American patient populations with type 2 DM.  In intervention group (one practice site), patients were informed and asked to participate if they met inclusion criteria. Most agreed to participate. In control practice, patient charts were reviewed to identify those with same conditions (noted in inclusion criteria). Data were abstacted from medical records for the time period of this study (October 2000 - October 2001).

Design -  Time Series Study with Concurrent Controls

Blinding used (if applicable) - not applicable

Intervention (if applicable) - Care redesign process to provide access to a full range of diabetic management services, including nurse-led planned care visits using evidence-based clinical management, patient education and support for self-management through a group visit structure, making decision support tools available for providers, and providing a new clinical information system (patient registry). Intervention design and content was informed by recommendations of the American Diabetes Association, included teaching points, group visit materials, encouragement of patient-to-patient interaction, and educational handouts selected and targeted to meet the unique needs of the target population, primarily rural African Americans. Patients were assigned to a group of 3-12 who met for a series of four, 2-hour group sessions over a period of 6 months. The sessions were led by an interdisciplinary team consisting of regional providers, and focused on overview of diabetes, nutrition, medication, and self-management/goal-setting.

Statistical Analysis  - Median HbA1c compared at baseline and 12 months using Mann-Whitney U-test. Median HbA1c, weight, and BP were compared within group (intervention or control, but across time) using a Wilcoxon rank sum test. Percentage of patients with HbA1c below 7% and percentage with a reduction were calculated at both baseline and at follow-up and compared using a Wilcoxon rank sum test.

 

Data Collection Summary:

Timing of Measurements: Baseline, 12 months after enrollment.

 Dependent Variables

  • HbA1c - measurement method not described
  • Blood Pressure (BP) -  measurement method not described
  • Weight - measurement method not described

Independent Variables

  • Group educational sessions for intervention group
  • Chart record review for control group, usual care not described

 Control Variables not specified

 

Description of Actual Data Sample:

Initial N: 160 (112 intervention, 48 control). 57% female in intervention group, 52% in control group.

Attrition (final N):   160. All patients who participated in intervention were included in the analysis.

Age: 60 ± 13 for intervention group; 58 ± 17 years for control group. 

Ethnicity: over 90% African American in both intervention and control group.

Other relevant demographics: Anthropometrics:  There were no significant differences between groups in terms of age, ethnicity and gender.

Location: rural North Carolina.

 

Summary of Results:

 

Variables

Treatment Group (n=112)

Control group (n=48)

Statistical Significance of Group Difference

Baseline Median HbA1c

8.2 ± 2.6

 8.3  ± 2.0

 p<.0001

Follow-up Median HbA1c

7.1 ± 2.3

 8.6 ± 2.4

 p<.05

Other Findings

More than 60% of patients in intervention group responded with some reduction in their HbA1c.

No significant differences in mean weight or BP measurements between baseline and follow-up in intervention group.

Author Conclusion:
A revised care management system that includes nurse-led visits and a group visit structure can be successfully incorporated into a rural primary care practice seeing predominately African Americans and appears to produce improved clinical outcomes compared to usual care. These findings support the work of previous investigators who have employed similar strategies with other patient groups.
Funding Source:
Reviewer Comments:
Measurement of dependent variables not described.  Usual care in control group not described. Groups not similarly sized. Includes a good discussion of the limitations of this study, including a potential for selection bias. The improvements in glycemic control have positive clinical implications.
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? ???
  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) ???
  3.2. Were distribution of disease status, prognostic factors, and other factors (e.g., demographics) similar across study groups at baseline? Yes
  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? 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? 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%.) 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? Yes
  5.1. In intervention study, were subjects, clinicians/practitioners, and investigators blinded to treatment group, as appropriate? 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.) Yes
  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? Yes
  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
  6.3. 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
  6.6. Were extra or unplanned treatments described? No
  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? 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? ???
  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? ???
  7.7. Were the measurements conducted consistently across groups? ???
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