In a cross-society comparison, we assessed the state of mothers' knowledge of child rearing and child development. The study included 1,077 mothers from five countries on four continents: Argentina, Belgium, Italy, South Korea, and the United States. A criteria-referenced instrument, the Knowledge of Infant Development Inventory, was used to assess parenting knowledge after being adapted for cross-society comparison using item response theory and the alignment optimization approach for testing between-sample measurement invariance. Levels of mothers' parenting knowledge varied across the five societies and were associated with different sociodemographic factors and personal and non-personal supports.
Keywords: cross-society differences; differential item functioning; measurement invariance; parenting knowledge.