Score contribution per author:
α: calibrated so average coauthorship-adjusted count equals average raw count
We study the effect of economic conditions early in life on the occurrence of type‐2 diabetes in adulthood using contextual economic indicators and within‐sibling pair variation. We use data from Lifelines: a longitudinal cohort study and biobank including 51,270 siblings born in the Netherlands from 1950 onward. Sibling fixed‐effects account for selective fertility. To identify type‐2 diabetes we use biomarkers on the hemoglobin A1c concentration and fasting glucose in the blood. We find that adverse economic conditions around birth increase the probability of type‐2 diabetes later in life both in males and in females. Inference based on self‐reported diabetes leads to biased results, incorrectly suggesting the absence of an effect. The same applies to inference that does not account for selective fertility.