Modeling the volume-effectiveness relationship in the case of hip fracture treatment in Finland.
BACKGROUND
A common argument in the recent health policy debate is that treatment is more effective among care providers with large volumes. It is challenging, however, to examine the volume-effectiveness relationship empirically. Several suggestions have recently been made for methodological improvements in the examination of the volume-effectiveness relationship. The aim of this study is to develop an extended methodology for examining the volume-effectiveness relationship and demonstrate it for the case of hip fracture treatment.


METHODS
Data consisting of 22,857 hip fracture patients from 52 hospitals in Finland in 1998-2001 were extracted from the administrative registers. The relationship between hospital and rehabilitation unit volumes and effectiveness was examined using a statistical model that allowed risk adjustments and hierarchical modeling of volume trends, developed for the purposes of this study. Four-month mortality and the alternative register-based measure of maintainability were used as effectiveness indicators.


RESULTS
No clear relationship was found between hospital volume and the effectiveness of hip fracture treatment, but a novel result showing an association between the rehabilitation unit volume and effectiveness was detected. The face validity of the maintainability indicator seemed to be acceptable.


CONCLUSIONS
The methodological ideas presented allow for improved examination of the volume-effectiveness relationship. There are no indications that patients with hip fractures should only be treated in high-volume hospitals, though it may be beneficial to centralize the rehabilitation of hip fracture patients to specialized units.
Sund
Reijo
R
Service Systems Research Unit, National Institute for Health and Welfare, PO Box 30, FI-00271 Helsinki, Finland. reijo.sund@thl.fi
D000368:Aged; D005260:Female; D005387:Finland; D006620:Hip Fractures / Q000534:rehabilitation* / Q000601:surgery*; D006757:Hospital Units / Q000706:statistics & numerical data*; D006761:Hospitals / Q000706:statistics & numerical data; D006801:Humans; D016015:Logistic Models; D008297:Male; D012042:Registries; D020379:Risk Adjustment; D016896:Treatment Outcome