Unwarranted geographic variation in paediatric health care in the US and Norway

Aim We present the four US and Norwegian paediatric and neonatal health atlases and discuss the concept and causes of unwarranted geographic variation in paediatric health care. Methods The four atlases analyse data from both publicly owned health registers, registers of insurance claims and quality registers. Healthcare utilisation is counted per recipient in predefined hospital service areas, adjusted for relevant confounders and presented as extremal ratios between the highest and lowest rate. Results The atlases describe geographic variation in rates for primary health care, hospital admissions, outpatient visits, treatment procedures and diagnostic testing. A difference in extremal ratios from 2 to 4 between health service areas are common, and for some procedures extremal ratios is even higher. Conclusion Variation in healthcare utilisation of the magnitude described in these four atlases cannot be explained by differences in population morbidity or patient preferences and are therefore characterised as unwarranted variation. Individual provider preferences or supply of resources such as hospital beds may explain the observed variation.