Monitoring of the Implementation of a Breastfeeding Guideline for 6 Years: A Mixed-Methods Study Using an Interrupted Time Series Approach.

BACKGROUND Current literature provides poor information about the implementation of health-promoting clinical practice guidelines (CPGs) and their longitudinal monitoring. PURPOSE The aim of this study was to evaluate the longitudinal impact of a CPG implementation program that promotes breastfeeding, its associated quantitative and qualitative indicators, and direct costs. DESIGN A mixed-methods design with a longitudinal approach was utilized, with an interrupted time series design and the analysis of reports from the implementation program as the qualitative approach. METHODS The study setting was maternity and pediatric units of a health area in the Spanish health system. The implementation of a CPG for the promotion of breastfeeding was evaluated, which included a pre-implementation year (2011), 3 years of implementation (2012-2014), and 2 years of post-implementation (2015-2016). The sample was composed of mother-infant dyads. A segmented logistic regression analysis was utilized to evaluate the changes in the most important breastfeeding indicators. A deductive thematic content analysis was performed starting with quality indicators and a descriptive economic analysis. FINDINGS In the 6 years of monitoring, 7,842 mother-infant dyads were recorded. The results of the quantitative indicators showed the presence of four stages: baseline, gain, adjustment, and sustainability or saturation. The breast milk at the first feeding had an increasing slope in the gain stage (24% per quarter; odds ratio [OR] = 1.24, 95% confidence interval [CI] 1.12-1.37). The exclusive breastfeeding at hospital discharge showed significant changes in the period of gain (OR = 2.45, 95% CI 1.95-3.08), which was maintained in the adjustment period, with an increase of 18% in the slope of the gain stage (OR = 1.18, 95% CI 1.06-1.32). The longitudinal distribution of the qualitative indicators showed a greater concentration of indicators towards the first half of each phase. The total cost was 209,575€ ($248,670.17). CONCLUSIONS The implementation of the breastfeeding CPG showed early, positive, and sustained results in the exclusive breastfeeding rates. The implementation implied the application of a complex intervention, with its qualitative indicators showing a wave-shaped dynamic. CLINICAL RELEVANCE Our findings contribute to the understanding and evolution of the main indicators of the implementation of a breastfeeding CPG, providing details on the magnitude of the effect, the process of change, and the associated costs.