LAUSR

Background Infant and young child feeding (IYCF) practices are important for child survival and healthy growth, but IYCF practices remain suboptimal in Nigeria. The objective of this study was to measure the impact of Alive & Thrive’s IYCF social and behavior change communication intervention on early initiation of breastfeeding, exclusive breastfeeding, and minimum dietary diversity in Kaduna and Lagos States. Methods Local government areas were randomly allocated to intervention or comparison. Cross-sectional surveys of households with children aged 0–23 months were conducted [N = 6,266 baseline (2017), N = 7,320 endline (2020)]. Logistic regression was used to calculate difference-in-differences estimates (DDEs) of impact on IYCF practices and to assess within group changes from baseline to endline. Associations between intervention exposures and IYCF practices were tested in both study groups combined. Results In Kaduna, a positive differential effect of the intervention was found for exclusive breastfeeding (adjusted DDE 8.9 pp, P<0.099). Increases in both study groups from baseline to endline were observed in Kaduna for early initiation of breastfeeding (intervention 12.2 pp, P = 0.010; comparison 6.4 pp, P = 0.118) and minimum dietary diversity (intervention 20.0 pp, P<0.001; comparison 19.7 pp, P<0.001), which eliminated differential effects. In Lagos, no differential intervention impacts were found on IYCF practices because changes in early initiation of breastfeeding from baseline to endline were small in both study groups and increases in both study groups from baseline to endline were observed for exclusive breastfeeding (intervention 8.9 pp, P = 0.05; comparison 6.6 pp, P<0.001) and minimum dietary diversity (intervention 18.9 pp, P<0.001; comparison 24.3 pp, P<0.001). Odds of all three IYCF practices increased with exposure to facility-based interpersonal communication in both states and with community mobilization or mass media exposure in Kaduna. Conclusions This evaluation found weak impacts of the Alive & Thrive intervention on IYCF practices in the difference-in-differences analysis because of suspected intervention spillover to the comparison group. Substantial within group increases in IYCF practices from baseline to endline are likely attributable to the intervention, which was the major IYCF promotion activity in both states. This is supported by the association between intervention exposures and IYCF practices. Trial registration The study was registered with clinicaltrials.gov (NCT02975063).