Study design and location
This study was an open-label, parallel two-arm cluster randomized controlled trial done within a pregnancy cohort in which the use of the MCH handbook was compared with the use of two stand-alone home-based records during maternity and childcare service use in Angola. We purposively selected the Benguela province, as its health indicators are close to the national average, thus representing an ideal setting to show intervention impact on MCH outcomes and demonstrate the feasibility for a nationwide scale-up of the MCH handbook in Angola. We favored the cluster randomization design due to the nature of the intervention and because it minimized logistical and scientific difficulties associated with individual randomization in large-scale longitudinal studies. The central study center in Angola was based at the Benguela office of Domus Custodius Holding TCHIKOS Consulting Agency, and the overall study coordinating center was at the National Center for Child Health and Development, Tokyo Japan.