Referral of paediatric patients follows geographic borders of administrative units.

Introduction: This observational study examines changes in paediatric hospital-seeking behaviour at Kolding Hospital in The Region of Southern Denmark (RSD) following a major change in administrative units in Denmark on 1 January 2007.

Material and methods: Data on the paediatric admissions from 2004 to 2009 reported by department of paediatrics and municipalities were drawn from the Danish National Hospital Registration. Patient hospital-seeking behaviour was related to changes in the political/administrative units. Changes in number of admissions were compared with distances to the corresponding departments.

Results: From 2006 to 2009, the number of acute and planned admissions at the Department of Paediatrics in Kolding for children living in the RSD increased by 46.1% and 65.0%, respectively. The corresponding changes for children living in the neighboring region, the Central Denmark Region (CDR), were -69.9% and -78.6%.

Conclusion: The geographical location of the department under study and the changes in administrative units created a "natural experiment" that showed major changes in paediatric hospital-seeking behaviour. Within the RSD, the free choice of hospitals seemed to work, whereas the new boundary between the CDR and the RSD meant that paediatric patients were admitted at hospitals situated in the CDR even though the distances to these hospitals were considerably longer than those to other hospitals. One could question whether patients really have a free choice across administrative borders as political and economic concerns seemed to outweigh free patient choice.

Funding: not relevant.

Trial registration: not relevant.