Health Disparities

MNT: Disorders of Lipid Metabolism (2015)

Citation:

Gans KM, Burkholder GJ, Risica PM, Harrow B, Lasater TM. Cost-effectiveness of minimal contact education strategies for cholesterol change. Ethn Dis. 2006 Sprin; 16(2): 443-451.

PubMed ID: 17682247
 
Study Design:
Randomized Controlled Trial
Class:
A - Click here for explanation of classification scheme.
Quality Rating:
Neutral NEUTRAL: See Quality Criteria Checklist below.
Research Purpose:

To compare the effectiveness and cost effectiveness of six minimal contact nutrition interventions on blood cholesterol levels.

Inclusion Criteria:

Not described.

Exclusion Criteria:

Not described.

Description of Study Protocol:

Recruitment

  • Rolling recruitment to control for seasonality effects
  • Sites were randomized into one of the six nutrition education interventions so that all participants at a given site were exposed to the same intervention
  • Methodology included poster, flyers, face-to-face recruitment, table tents, and so on. The efforts targeted Hispanic participants.

Design

Randomized.

Intervention

  • All study intervention and evaluation materials were provided in English or Spanish according to the participant's preference
  • The Spanish language materials were developed to be culturally appropriate to the local Hispanic population.
  • At baseline:
    • Basic tracking and demographic information
    • Questionnaire regarding health behaviors and risk factors
    • Written survey containing dietary and psychosocial questions
    • Weight measured
    • Blood cholesterol screening
    • Assignment to one of the six (site-specific) nutrition education interventions
  • Assignment of one of the nutrition education interventions:
    • The first three interventions included take-home written materials only:
      • Cholesterol Result Form (CRF):
        • Blood cholesterol value
        • An outline of the NCEP referral recommendations for each blood cholesterol category
        • Basic information about blood cholesterol and diet
      • CRF plus Rate Your Plate (RYP):
        • As above, plus
        • RYP self-scoring instrument for eating pattern assessment focusing on food behaviors that contribute to fat, saturated fat and cholesterol intake
      • CRF + RYP + Let's Eat Kit (LEK)
        • As above, plus
        • LEK: A three-ring binder with detailed information on food choices, label reading, dining out, healthful recipes, etc.
    • The next three interventions included a RYP during enrollment, all of the written material, plus counseling by one of three methods
      • Compact disc audio (AUD): Self-selected tracks containing educational information that corresponded to the RYP food categories while viewing a book of food photographs that also corresponded to the RYP food categories
      • Lay administered face-to-face counseling (LAY-C): Trained counselor provided a brief (10- to 12-minute) session using the LEK
      • Nutritionist administered face-to-face counseling (NUT-C): provided a brief (10- to 12- minute) session using the LEK
  • Follow-up:
    • Completion of a telephone survey followed by another in-person screening at the same site as baseline.

Statistical Analysis

  • ANOVA was used to identify potential confounding variables. Parameters were added to the basic model if they caused a 10% change.
  • Main effects were tested by mixed regression models.

Cost Analysis

  • Screening costs included all supplies for measuring blood cholesterol, height and weight equipment and screening staff time
  • Educational costs included the costs for reproduction of material as well as counseling staff time
  • The condition-specific cost-effectiveness ratio was computed as the total cost per participant minus the cost of intervention #1 divided by the difference in blood cholesterol change between the condition in question ad intervention #1.
Data Collection Summary:

Timing of Measurements

Baseline, three months and 12 months after intervention. 

Dependent Variables

Variable 1: Total blood cholesterol.

Independent Variables

  • Cholesterol Result Form (CRF)
  • CRF plus Rate Your Plate (RYP)
  • CRF, RYP, plus Let's Eat Kit (LEK)
  • All written materials plus CD audio intervention (AUD)
  • All written materials (CRF + RYP + LEK) plus counseling from a trained lay person (LAY-C)
  • All written materials (CRF + RYP + LEK) plus counseling by a nutritionist (NUT-C). 

Control Variables

  • Age
  • Gender.
Description of Actual Data Sample:

Initial N

10,144 participants; 60% women.

Attrition (Final N)

Percent of participants completing follow-up:

 

Three

months

12 months
Telephone survey 90% 84%
Blood cholesterol screening 81% 76%
  • Response rates were lower for Hispanics compared with NHW participants
  • The reasons for attrition at three months and 12 months were identified.

Age

Mean age of 49 years.

Ethnicity

  • 77% non-Hispanic White
  • 14% Hispanic
  • 5.5% African American
  • 1% Asian
  • 1% Native American.

Anthropometrics

Differences among groups were idenified: FHQ (P<0.0001), regular exercise (P<0.005), previous BC measure (P<0.001), have high blood glucose (P<0.001), have high BP (P<0.001), on high BP medicationss (P<0.001).

Location

Southern New England; a total of 144 site in four different sectors (public sites, medical facilities, religious organizations, work sites).

 

Summary of Results:

 

Key Findings

Variables

Treatment Group

Measures and Confidence Intervals

Control Group

Measures and Confidence Intervals

Statistical Significance of Group Difference

Blood cholesterol at three months

Mean, CI.

e.g., 4.5±2.2

Mean, CI.

e.g., 1.5±2.0

Stat significant difference between groups

e.g., P=0.002

 

Mean Cholesterol Change (SE)
     CRF  RYP LEK AUD LAY-C  NUT-C
Full Sample (N=10,144)              
  Three-month change         -2.9(1.4)* -4.5(1.4)*
  12-month change   -5.0 (1.4)* -3.1(1.4)* -4.6 (1.4)*   *-4.0 (1.4)
Non-Hispanic white and Hispanic participants Three- month change       -6.1(2.9)*   -7.2 (3.5)*
  12- month change       -8.1(2.8)*    

 *Significantly different from zero.

 

  • All people with elevated blood glucose (higher than 200mg per dL) responded to the assigned experimental conditions, i.e., all achieved decreased blood cholesterol values
  • Generally the conditions that received counseling achieved the greatest reduction in blood cholesterol values. 

Cost Effectiveness of Intervention as a Function of Blood Cholesterol Change (mg per dL)

    Total Cost per mg Blood Cholesterol (in Dollars) Total Education Costs (Excludes the Cost of Cholesterol Screening, in Dollars)
CRF Three-month change 11.90

0.08*

  12-month change 3.39 0.02§
RYP Three-month change 2.95* 0.12
  12-month change 1.48§ 0.06
LEK Three-month change 12.59 4.72
 

12-month change

3.65 1.37
AUD Three-month change 7.32 3.78
  12-month change 3.18 1.64
LAY-C Three-month change 4.73 2.29
  12-month change 5.72 2.77
NUT-C Three-month change 4.83 3.25
  12-month change 5.40 3.66

* Lowest cost at three months; § lowest cost at 12 months.

Other Findings

The NUT-C condition was more cost-effective when the participant had an increased baseline blood cholesterol.

  • 12-month cost was $1.72 per mg per dL decrease if the baseline cholesterol was between 200 and 239mg per dL
  • 12-month cost was $1.01 per mg per dL decrease if the baseline cholesterol was greater than 240mg per dL. 

 

Author Conclusion:

Brief nutrition counseling is an effective component of blood cholesterol reduction programs. Hispanic participants were responsive to culturally tailored interventions. This range of interventions is fairly inexpensive compared to other, more intensive clinical interventions.

Funding Source:
Government: NHBLI
Reviewer Comments:
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? ???
  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? No
3. Were study groups comparable? ???
  3.1. Was the method of assigning subjects/patients to groups described and unbiased? (Method of randomization identified if RCT) Yes
  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? 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%.) Yes
  4.3. Were all enrolled subjects/patients (in the original sample) accounted for? Yes
  4.4. Were reasons for withdrawals similar across groups? Yes
  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? No
  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.) No
  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? 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? 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? No
  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? 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? Yes
  7.6. Were other factors accounted for (measured) that could affect outcomes? No
  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? No
  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? No
  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)? 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? No
  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