Cindy-Lee Dennis, PhD

 

Other Breastfeeding Self-Efficacy Research Activities

The following is a short selection of Dr. Dennis’s research initiatives with her instrument.

Refinement of the Breastfeeding Self-Efficacy Scale – Development of the Short-Form

Although psychometric support for the validity and reliability of the BSES was established with Dr. Dennis’s initial methodological study, internal consistency statistics and multiple factor loadings suggested a need for item reduction. As such, through secondary analysis of Dr. Dennis’s postdoctoral work she refined the original BSES and psychometrically assessed the revised BSES-short form (BSES-SF). Based on an extensive literature review, she developed the following criteria to delete items: (1) item mean of 4.2 or more (to increase variability); (2) corrected item-total correlation less than 0.60 (to increase overall item fit); (3) item with 10 or more inter-item correlations below 0.40 (to increase homogeneity); and (4) inter-item correlation above 0.80 (to decrease redundancy). Using these item statistics, the 33-item BSES was shortened to 14 items. The reliability estimates of the BSES-SF, including Cronbach’s alpha coefficient, inter-item correlations, and corrected item-total correlations, demonstrated excellent internal consistency. Through this refinement process, the BSES-SF has even greater clinical utility due to ease of administration.

Translation of the Breastfeeding Self-Efficacy Scale

Frequently non-English speaking populations are excluded from clinical research due to the lack of reliable and valid instruments to measure variables of interest. To date, many instruments have been developed and validated among English-speaking populations with few being translated into other languages and re-evaluated psychometrically. This is a significant limitation given the fact that multilingual and multicultural societies will become the norm for many countries in the 21st century. Many studies using ethnic samples have assumed that methodologies and assessment tools can be used cross-culturally. However, this practice disregards possible changes in psychometric properties due to translation bias or inaccuracies and it ignores the impact that culture may have on the meaning of scale items. To address this issue, Dr. Dennis has actively participated in the translation of her BSES scale into diverse languages including: French, Mandarin, Spanish, Polish, Italian, Greek, Portuguese, Japanese, and Thai.

Psychometric Testing of the Breastfeeding Self-Efficacy Scale with Diverse Populations

  1. Australian Mothers. In collaboration with Dr. Debra Creedy from Griffith University in Brisbane, the BSES was psychometrically tested among 300 Australian mothers providing further evidence for the reliability and validity of my instrument.
  2. African-American Mothers. In collaboration with Dr. Debra McCarter-Spaulding from Saint Anselm College in Manchester, New Haven, Dr. Dennis assisted in psychometrically testing the BSES-SF among 153 Black mothers. These women completed the BSES-SF during their first postpartum week and were follow-eup to 24 week spostpartum.
  3. Adolescent Mothers. A graduate student (Marion Mossman) as part of her thesis at the University of Manitoba, Faculty of Nursing recruited 101 pregnant adolescents from two prenatal clinics in Winnipeg, Manitoba to psychometrically test the BSES-SF antenatally and in the immediate postpartum period.
  4. Mothers of Premature Infants. In collaboration with Barbara Wheeler, a clinical nurse specialist at the St. Boniface General Hospital in Winnipeg, Manitoba, mothers of ill and/or preterm infants (N = 144) were recruited from three hospital units to psychometrically test the BSES-SF within the first week postpartum, at infant hospital discharge, and 6 weeks post-discharge. For this methodological study, the BSES-SF was modified resulting in 18 items that included many from the original scale, with others suggested by (1) a comprehensive literature review, (2) mothers of ill and/or preterm infants who were successful in breastfeeding, and (3) expert clinicians.
  5. Ethnic UK Mothers. As a 4th-year undergraduate project, three medical students under the supervision of Dr. Christine McArthur at Birmingham University administered the BSES-SF before hospital discharge to breastfeeding mothers (54% were Southeast Asian) and then via mail questionnaires at 6 weeks postpartum.

Breastfeeding Self-Efficacy Predictive Model

While research suggests that the BSES could be used in the early postpartum period as an identification tool to distinguish between those mothers who are likely to succeed at breastfeeding and those who require additional intervention to ensure continuation, no study has been conducted to determine which mothers are at particular risk to experience low breastfeeding self-efficacy. As such, Dr. Dennis developed a multi-factorial predictive model of breastfeeding self-efficacy in the first week postpartum in order to assist in the identification of mothers at risk to discontinue breastfeeding prematurely. As part of her postdoctoral work, a population-based sample of 522 breastfeeding mothers in a health region near Vancouver, British Columbia completed mailed questionnaires at 1 and 8 weeks postpartum. The best-fit regression model revealed eight variables, which explained 54% of the variance in BSES scores at 1-week postpartum: maternal education, support from other women with children, type of delivery, satisfaction with labour pain relief, satisfaction with postpartum care, perceptions of breastfeeding progress, infant feeding method as planned, and maternal anxiety. By administering the BSES and through an examination of the risk factors identified, health professionals have the potential to improve the quality of care that they deliver to new breastfeeding mothers.

Breastfeeding Self-Efficacy Scale Cut-Off Scores

Today, Dr. Dennis does not recommend cut-off scores.

Pilot Randomized Controlled Trial

Dr. Dennis’s research has consistently demonstrated the predictive ability of BSES scores in the immediate postpartum period on breastfeeding duration and exclusivity. The next stage in this research is to determine whether breastfeeding self-efficacy can be enhanced via interventions by health professionals to improve breastfeeding outcomes. As such, one of her PhD students, Karen McQueen, pilot tested a breastfeeding self-efficacy enhancing intervention. This pilot work has been used to develop a large multi-site randomized controlled trial.

Large Randomized Controlled Trial

Objective: To evaluate the effect of a breastfeeding self-efficacy enhancing intervention provided by a professional and peer team on breastfeeding exclusivity among primiparous mothers.

Background: Leading health authorities such as the World Health Organization, Canadian Paediatric Society and the American Academy of Pediatrics all recommend breastfeeding as the optimal method of infant feeding. These recommendations suggest that infants be breastfed exclusively for the first 6 months of life and then, once other foods have been introduced, continue to be breastfed until 2 years and beyond. This strong endorsement is based on compelling evidence that breastfeeding offers important infant and maternal health benefits and has significant economic implications. Despite these benefits and a breastfeeding initiation rate of 90% in Canada, a recent nation-wide survey found that only 27% of mothers are exclusively breastfeeding to 6 months postpartum. This rate is significantly lower than other industrialized countries including Australia. Given that breastfeeding has a dose-response effect, with increased benefits being proportionate to the extent of duration and exclusivity, these suboptimal breastfeeding rates indicate that mothers and infants are not receiving the maximum health benefits. To address this issue, numerous trials have been conducted to evaluate the effect of additional support on breastfeeding outcomes. A Cochrane systematic review suggests that extra breastfeeding support is beneficial but professional or lay support provided alone is insufficient to significantly increase breastfeeding exclusivity rates to 6 months postpartum. A potential promising intervention is the combination of professional and lay support. To target these breastfeeding support interventions, many health professionals have enrolled mothers at high risk to prematurely discontinue breastfeeding based on non-modifiable demographic characteristics (e.g., maternal age, marital status, education level, socioeconomic status). However, if health professionals are to effectively improve low breastfeeding exclusivity and duration rates, they need to reliably assess high-risk mothers and identify predisposing factors that are amenable to intervention. Conceptually developed by Dennis, breastfeeding self-efficacy is one possible modifiable variable that consistently identifies high-risk mothers among varying maternal populations and is significantly associated with breastfeeding initiation, duration, and exclusivity. Three studies have evaluated the effect of a self-efficacy enhancing intervention on breastfeeding outcomes, but the results are questionable due to significant methodological limitations. No research has evaluated the effect of a breastfeeding self-efficacy enhancing intervention on breastfeeding exclusivity provided by a professional and peer team.

Design Overview: The current study is a randomized controlled trial with hospital stratification. Primiparous breastfeeding mothers are briefly introduced to the study by a postpartum hospital nurse and referred to the research nurse for a detailed explanation. Following informed consent procedures, all eligible and consenting women are randomly allocated to either the intervention group (breastfeeding self-efficacy enhancing intervention) or control group (the standard postpartum care). Participants allocated to the intervention group (n= 478) will receive standard postpartum care plus four individualized self-efficacy enhancing sessions with a trained research nurse; mothers will also be offered telephone-based peer support following hospital discharge up to 12 months postpartum. Participants in the control group (n = 478) will only receive standard in-hospital and community postpartum care. A research assistant blinded to group allocation will telephone all mothers at 3, 6, 9, and 12 months postpartum to collect outcome data.  At 3 months, participants in the intervention group will also evaluate their satisfaction with the intervention. Relevance: The results from this trial will make substantive contributions in five areas: (1) advance the body of knowledge concerning the effectiveness of a breastfeeding self-efficacy enhancing intervention on improving breastfeeding outcomes; (2) examine the utility of providing professional and lay support in the provision of breastfeeding care; (3) provide an economic evaluation of a breastfeeding support intervention;  (4) examine maternal and infant health service utilization in relation to infant feeding method; and (5) present valuable information regarding breastfeeding behaviours across the first year postpartum in a diverse Canadian sample.