Using the Medical Research Council Framework for the Development and Evaluation of Complex Interventions in a Theory-Based Infant Feeding Intervention to Prevent Childhood Obesity: The Baby Milk Intervention and Trial

Table 3

Intervention and Control contacts and content.

Timeline	Intervention group (IG)	Control group (CG)
First: face-to-face.; Within 14 weeks of birth	(i) Healthy growth and nutrition leaflet.; (ii) Stickers for formula-milk packets/tins with new guideline daily requirements.; (iii) Education about growth charts, rapid weight gain, obesity risk.; (iv) Personal feeding plan (PFP).; (v) Model feed preparation if necessary.	(i) Standard Department of Health bottle feeding leaflet.; (ii) General questions about formula-milk feeding, information sources, and decisions.
Second: telephone.; 3-4 months (3–6 weeks later)	(i) Check understanding of key messages.; (ii) Review of PFP and goal setting.	General questions about sleep and support with caring for baby.
Third: face-to-face (IG)/telephone (CG); 4-5 months (3–6 weeks later)	(i) Feedback on growth.; (ii) Weaning advice.; (iii) Review of PFP and goal setting.	General questions about life after the baby’s birth.
Fourth: telephone.; 5-6 months (3–6 weeks later)	Review of PFP and goal setting.	General questions about formula-milk changes and weaning
Fifth: face-to-face.; 6-7 months (3–6 weeks later)	(i) Feedback on growth.; (ii) Review of PFP and goal setting.	(i) Standard Department of Health weaning leaflet.; (ii) Questions about experience of taking part in the study and research in general.

Identification of barriers and facilitator, problem solving, and “If…then plans” are used in all contacts. All contacts are underpinned by good communication skills. The motivation ruler and confidence ruler are used for assessment and to prompt identification of barriers and facilitators. The “cost-benefit analysis” tool is used as required to improve motivation and confidence.