Universal Investments in Toddler Health. Learning from a Large Government Trial
2026-05-01
Exploiting a 1960s government trial in Copenhagen, we study the long-run effects of preventive health care for toddlers. We combine administrative data with handwritten nurse records to document universal treatment take-up. Treated children enjoy a five percent of a standard deviation increase in a good adult health index. While initial trial cohorts experience positive health and labour market impacts, those are absent for the final cohorts. Impacts are largest for children with initial health disadvantage and females, and we identify childhood health improvements as a core mechanism. The heterogeneity of trial effects across individuals’ initial health status and cohorts documents that universal toddler care can alleviate health inequalities at low costs, and that the counterfactual policy environment matters.