Health Disparities

HD: Effectiveness of Nutrition Intervention Methods (2010)

Anderson AK, Damio G, Young S, Chapman DJ, Pérez-Escamilla R.A randomized trial assessing the efficacy of peer counseling on exclusive breastfeeding in a predominantly Latina low-income community. Arch Pediatr Adolesc Med. 2005 Sep; 159(9): 836-841. 
PubMed ID: 16143742
Study Design:
Randomized Controlled Trial
A - Click here for explanation of classification scheme.
Quality Rating:
Positive POSITIVE: See Quality Criteria Checklist below.
Research Purpose:

To assess the efficacy of peer counseling to promote exclusive breastfeeding among low-income inner city women.

Inclusion Criteria:
  • Initial screening criteria:
    • 18 years or older
    • Gestational age of 32 weeks or younger
    • Healthy
    • Absence of any medical condition likely to impair successful breastfeeding
  • Secondary screening:
    • Considering breastfeeding
    • Planning to deliver at Hartford Hospital
    • Willing to stay in the area for at least three months after delivery
    • Available to be contacted by telephone
    • Willing to participate in the study
  • Tertiary screening (during hospitalization) of the infant:
    • Born at term (36 weeks or more gestation)
    • Normal birth weight (2.5kg or more)
    • No neonatal medical complications requiring NICU admission
    • Apgar scores at one and five minutes of six or higher.
Exclusion Criteria:
  • Medical conditions that would impair successful breastfeeding
  • NICU admission after the infant was born.
Description of Study Protocol:


Participants were recruited fro the waiting areas of three prenatal clinics.


Randomized controlled trial.


  • Participants were randomized. The control group received conventional prenatal breastfeeding information and support from the maternity ward staff after delivery.
  • The peer counseling group received three prenatal home visits, nine post-partum home visits, daily in-hospital visits from the assigned peer counselor. They had both the beeper and the cell phone number of the peer counselor to be contacted if a lactation crisis occurred between scheduled home visits.
  • The peer counselor received a two-week training session conducted by an IBCLC and was supplemented by a two-month period of observation.

Statistical Analysis

  • Chi-square analysis for between group and across time differences in sociodemographic and biomedical parameters
  • ANOVA used to determine between-group differences in continuous variables
  • Analysis completed on an intention-to-treat basis
  • Results were considered significant if the 95% confidence interval included unity.


Data Collection Summary:

Timing of Measurements

At the time of recruitment; during the post-partum hospitalization; weekly during the first month and biweekly during the second and third month via phone.

Dependent Variables

  • Variable 1: Exclusive breastfeeding status at hospital discharge
  • Variable 2: Exclusive breastfeeding status at one month post-partum
  • Variable 3: Exclusive breastfeeding status at two months post-partum
  • Variable 4: Exclusive breastfeeding status at three months post-partum.

The recall definitions for status were "the previous 24 hours," the "previous week," and "at three months, ever given."

Independent Variables

  • Peer counseling to support exclusive breastfeeding
  • Sociodemographic factors
  • Biomedical factors
  • Onset of lactation
  • Lactational amenorrhea
  • Infant morbidity
  • Gestational age at delivery
  • Infant birth weight and birth length
  • Apgar scores.

Control Variables

Low-income Latinas. 

Description of Actual Data Sample:
  • Initial N: 182 were recruited and randomized; 162 were eligible at delivery
  • Attrition (final N): 135
  • Age: The majority were between 20 and 30 years old
  • Ethnicity: Latina.

Other relevant demographics:

  • No significant difference was found between groups for maternal age, marital status, race/ethnicity, highest level of education, parity, previous breastfeeding experience, employment status, WIC participation, infant birth weight, onset of lactation
  • Significant difference was found between groups for preferred language, pregnancy intention (surprise vs. wanted later), planned breastfeeding duration, infant birth length.


Hartford, CT. 

Summary of Results:


Key Findings


  Relative Probability of Exclusive Breastfeeding by Intervention Group as Compared to Control Group
At hospital discharge 1.32 (95%CI 0.95 to 1.84)
One month 3.89 (95%CI 1.52 to 9.90)
Two months 17.24 (95%CI 2.33 to 125.84)
Three months 14.93 (95%CI 2.00 to 111.84)

Other Findings

No difference between the control and intervention group in the rate of not breastfeeding at three months was found.

Author Conclusion:

Breastfeeding support provided by both hospital and community-based peer counselors is effective in improving exclusive breastfeeding rates among low-income, inner-city women.

Funding Source:
Government: Centers for Disease Control and Prevention
Reviewer Comments:

This carefully planned study did not address one other source of support for exclusive breastfeeding, visits to the pediatrician. Information about instances of pediatrician support would have strengthened the results. Lack of this information does not appreciably weaken the results.

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? ???
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? 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? 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)? Yes
  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