HD: Food Security (2011)

Citation:
 
Study Design:
Class:
- Click here for explanation of classification scheme.
Quality Rating:
Research Purpose:

Purpose: To determine the effect of Food Stamp Nutrition Education in Indiana on participants' food insecurity and food insufficiency.

Hypothesis: The series of five tailored educational lessons provided through Food Stamp Nutrition Education would improve a participant's self-reported food security level and food sufficiency compared with participants receiving no Food Stamp Nutrition Education.

 

Inclusion Criteria:
  • Eligible to receive Food Stamp Nutrition Education services
    • ≥18 years or older
    • Qualified to receive food stamps or under 130% of the income-to-poverty ratio
    • Head of household, or person responsible for food purchases and food dollar management
  • Women.
Exclusion Criteria:
  • Not eligible to receive Food Stamp Nutrition Education Services
  • Men.
Description of Study Protocol:

Recruitment

  • Food Stamp Nutrition Education assistants were asked to volunteer to recruit participants
    • Assistants from 28 Indiana counties volunteered
    • Assistants from 24 Indiana counties recruited participants
  • Counties were composed of a representative mix of urban and rural areas.

Design

Single-blind randomized design

Blinding used

  • Food Stamp Nutrition Education assistants randomly assigned participants into the experimental or control group
  • Clients arriving together were assigned to the same group to prevent knowledge of a difference in treatment.

Intervention

  •  Food Stamp Nutrition Education lessons targeting food insecurity and nutrition
    • Education provided based on theoretical framework of social cognitive theory
    • Participants spend time with Food Stamp Nutrition Education assistant, a peer educator and a paraprofessional trained in nutrition education
    • Food Stamp Nutrition Education assistant models food preparation, healthful food selection, and cooking skills
    • Lessons include interactive presentation of the ideas discussed (e.g., preparing a meal, learning how to read food labels, visual examples of more and less healthful foods, practical tips on budgeting and thrifty food purchasing)
    • Lessons include five topical domains: MyPyramid, food groups, food safety, shopping behaviors and resource management and wellness.

Statistical Analysis

  • Chi-square analysis was used to compare participants' characteristics
    • Each measured independent variable and proportion of individuals classified to the various levels of food security or food insufficiency were compared
  • Pre-test, post-test and test difference scores were compared by two-sample T-test using the Satterthwaite test to account for sample size differences
  • Analysis of covariance models were constructed to find the effect of treatment group on food insecurity and food insufficiency
    • Missing data for the six-item US Food Security Scale were assigned values using the method outlined in the USDA Guide to Measuring Household Food Security
  • All statistical analysis were performed with SAS (Version 9.1, SAS Institute Inc., Cary, North Carolina, 2003).
Data Collection Summary:

Timing of Measurements

  • Participants were recruited, lessons were delivered,and food security questionnaires were collected from January 27, 2005 through October 14, 2005
  • Experimental Group
    • One Food Stamp Nutrition Education lesson
    • Complete questionnaire including food security or insufficiency measures
    • Receive four additional Food Stamp Nutrition Education lessons
    • Complete questionnaire again
  • Control (Delayed-Lesson) Group
    • One Food Stamp Nutrition Education lesson
    • Complete questionnaire including food security or insufficiency measures
    • Wait five weeks
    • Complete questionnaire again
    • Receive four additional Food Stamp Nutrition Education lessons.

Dependent Variables

  • Food insecurity quantified with six-item United States Household Food Security Scale
    • Modified to direct the participants to consider food eaten in their households over the past 30-days instead of the past 12 months
  • Food insufficiency quantified with United States Department of Agriculture Food Insufficiency Question.

Independent Variables

Food Stamp Nutrition Education lessons targeting food insecurity and nutrition

Control Variables

  • Age
  • High school diploma
  • Marital status
  • Household employment
  • Number fed in household
  • Food stamp use.
Description of Actual Data Sample:
  • Initial N: N=236
  • Attrition (final N): N=219
    • N=137, experimental group
    • N=82, control group
  • Age: ≥18 years
    • 18-39 years
      • N=91, experimental group
      • N=55, control group
    • 40-59 years
      • N=18, experimental group
      • N=10, control group
    • 60-100 years
      • N=27, experimental group
      • N=17, control group
  • Ethnicity:
    • 96.8% non-Hispanic white
    • 2.3% Hispanic
    • 0.5% black
    • 0.5% other
  • Other relevant demographics:
    • Female
    • Head of household
    • High School diploma
      • Yes
        • N=94, experimental group
        • N=57, control group
      • No
        • N=43, experimental group
        • N=25, control group
    • Marital status
      • Married/with partner
        • N=77, experimental group
        • N=38, control group
      • Single adult
        • N=60, experimental group
        • N=44, control group
    • Household employment
      • Yes
        • N=74, experimental group
        • N=35, control group
      • No
        • N=63, experimental group
        • N=47, control group
    • Number fed in household
      • One 
        • N=21, experimental group
        • N=18, control group
      • Two 
        • N=16, experimental group
        • N=15, control group
      • Three or more
        • N=100, experimental group
        • N=49, control group
    • Food Stamp use
      • Yes
        • N=72, experimental group
        • N=37, control group
      • No
        • N=65, experimental group
        • N=45, control group
  • Anthropometrics: Information not provided
  • Location: 24 Indiana counties
    • Food Stamp Nutrition Education lessons and food security questionnaires completed in client homes or at community locations where the clients were recruited
      • County offices of Special Supplemental Nutrition Program for Women, Infants and Children
      • Head Start centers
      • Food pantries.
Summary of Results:

Key Findings

  • Food security in the experimental group compared with the control group was significantly improved (R2=0.3073, β -0.37±0.17, P=0.03) after adjusting for pretest score and employment
  • Food insufficiency in the experimental group compared with the control group was significantly improved (R2=0.4384, β -0.08±0.04, P=0.04) after adjusting for pre-test score.

 

Other Findings

  • No significant differences between control and experimental groups
    • In self-reported characteristics of control and experimental groups
    • In initial food security or food insufficiency status
    • In proportion of individuals classified as food secure, food insecure without hunger, or food insecure with hunger
  • 40% of participants were food insecure.
Author Conclusion:
  • Food Stamp Nutrition Education was successful in improving participants' food insecurity and food insufficiency, indicating nutrition education is an appropriate intervention for food insecurity
  • Employed Food Stamp Nutrition Education participants and/or those with employed partners were able to improve household food security more than households without employment.
Funding Source:
University/Hospital: Purdue University Extension Program
Reviewer Comments:
  • Results may not apply to a more racially or ethnically diverse population
  • Asking about food security for the past 30 days immediately after lesson five may not have accurately captured the impact of the lessons.
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) Yes
  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? No
  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%.) No
  4.3. Were all enrolled subjects/patients (in the original sample) accounted for? Yes
  4.4. Were reasons for withdrawals similar across groups? ???
  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? Yes
  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? 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? 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? 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? 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
  9.1. 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