EAL

BF: Artificial Nipple and Duration of Breastfeeding (2008)

Citation:

Dulon M, Kersting M, Schach S. Duration of breastfeeding and associated factors in Western and Eastern Germany. Acta Paediatr 2001; 90: 931-935.

PubMed ID: 11529545

Study Design:

Prospective longitudinal study

Class:

B - Click here for explanation of classification scheme.

Quality Rating:

POSITIVE: See Quality Criteria Checklist below.

Research Purpose:

To examine the differences in breastfeeding behaviors and infant nutrition between former Western and Eastern Germany.

Inclusion Criteria:

Between March and May 1997, women delivering in specific two-week period assigned to each hospital.

Exclusion Criteria:

Infant birth weight <2,500g; Gestational age <37 weeks; admission to neonatal care unit; non-German-speaking; no telephone; late submission of written consent.

Description of Study Protocol:

Recruitment

177 out of 345 randomly selected hospitals participated in study.

Design

Prospective longitudinal study

Statistical Analysis

Chi-square or Fisher's exact test (comparisons between groups); Odds Ratio (OR) and confidence intervals (CI) to estimate Relative Risk; Multiple Logistic Regression; P<0.05 significant.

Data Collection Summary:

Timing of Measurements

Basic telephone interview 14±2 days post-partum (demographics, breastfeeding practices)
Mailed questionnaires at two, four, six, nine and 12 months post-partum (infant feeding practices)
Telephone interview to those who had stopped breastfeeding since the last questionnaire (reasons for stopping).

Dependent Variables

Long (≥ four months) vs. short-term (< four months) breastfeeding
Reasons for giving up breastfeeding (15 items, five-point Likert scale)

Independent Variables

Breastfeeding status assessed by WHO recommendations, combined into:

Breastfeeding only(exclusive or predominant, i.e. plus liquids)
Mixed (plus formula or weaning food)
Non-breastfeeding (no breastfeeding).

Control Variables

Factors significant in the univariate analysis were included in the multivariate model together with the exposure variable, location of maternal upbringing.

Description of Actual Data Sample:

Initial N

3,294 eligible women

Attrition (final N)

1,717 women completed initial; telephone interview; data in report from 1,593 mothers (80.3% Western and 19.7% Eastern Germany)

Age

89.9% and 66.7% of West and Eastern German women, respectively <25 years of age

Ethnicity

Eastern20% and Western 80% German descent

Other relevant demographics

33.9 and 23.3% Western and Eastern women, respectively >10 years education

Location

Research Institute of Child Nutrition, Dortmund, Germany

Summary of Results:

Factors associated with short-term breastfeeding, after adjusting for confounders (not significantly different between Western and Eastern women):

Variables	OR	95% CI	Statistical Significance of Group Difference
Supplementary feeding during first three days - Formula feeding vs. none - Water or tea feeding vs. none	2.92 1.80	1.65-5.24 1.38-2.35	P=0.003 P=0.001
Breastfeeding problems during first 14 days	2.41	1.88-3.10	P=0.001
Pacifier used during first 14 days	1.41	1.06-1.89	P=0.020

Also associated with shorted breastfeeding duration: Maternal age ≤ 25 years; single parent; low maternal education; partner's negative attitude towards breastfeeding.

Author Conclusion:

Not the geographical location, (East vs. West) but the different distribution of risk factors (social, cultural) was associated with short-term breastfeeding.

Funding Source:

Reviewer Comments:

Anthropometrics not reported (factors affect breastfeeding duration or success: Maternal (pre-pregnancy) weight/BMI, gestational weight gain, post-partum weight retention).

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)	N/A
	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?	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?	Yes
	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.)	Yes
	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?	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%.)	Yes
	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?		N/A
	5.1.	In intervention study, were subjects, clinicians/practitioners, and investigators blinded to treatment group, as appropriate?	N/A
	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?	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?	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?	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)?	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?	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