Baseline information about the mothers (e.g., demographics, maternal age, number of children, and previous breastfeeding experience) and their infants (e.g., gestational age, birth weight, ad- mission weight) was recorded at the time of study enrollment. Follow-up measurements were collected until the infant was 6 months old. Data on breastfeeding duration was collected at various point intervals directly from the mothers, as maternal recall has been shown to be valid and reliable for up to 3 years [15]. Mothers were given a diary upon discharge from the hospi- tal, and were instructed to fill out the diary in order to record information on formula and solid food introduction; timing of return to work; number of daily formula feeds and sessions at the breast at different points in time; any hospitalizations and reason; visits to primary care physicians and reasons; discussion with primary care physicians regarding breastfeeding; and visits to lactation support services.
A research assistant, blinded to group allocation, phoned participants 1 week after hospital discharge to remind them to complete their study diaries. Mothers were reminded by telephone to complete their diaries when the infant was 2, 3, 4 and 6 months old. We initially planned to collect feeding information both via diary and follow-up phone calls, so as to cross-reference the mothers’ answers for accuracy. However, some mothers did not return the diaries and oth- ers could not be reached via phone. Thus, 16 months into the study, we collected data by tele- phone for only those mothers who did not return the diaries.
To obtain feedback on the lactation support intervention on breastfeeding, we also included a secondary qualitative data collection component. This qualitative component was conducted with a subgroup of mothers from both the intervention and control groups.
For the intervention group, the interview guide featured 10 open-ended questions that fo- cused on the mothers’ perceptions of the intervention. Interviews occurred 1 week after the final lactation consultant session. Questions focused on mothers’ perceptions of breastfeeding prior to the intervention, their expectations of the study lactation consultant, and their experi- ence in the intervention.
Conversely, for the control group, the interview guide featured 7 open-ended questions that focused on the mothers’ perspectives on the standard of care they received for lactation support while in the hospital. Again, interviews occurred 1 week after hospital discharge