GP practice variation in hospitalisation rates: a study of partnership health-enrolled patients

This project aims to provide information to support the planning and implementation of strategies to reduce hospitalisation. It examines variations in hospital discharge rates between practice populations and the use of special general practice access funding.

Practice enrolment data for 345 254 patients enrolled with 102 Partnership Health Primary Health Organisation (PHO) general practices were sent to New Zealand Health Information Service. Data linked to the patient National Health Index (NHI) relating to hospital discharges were attached to the practice enrolment data for the two years ending June 2007 and returned to the researchers with the NHI numbers encrypted. Total discharges were 127426. The data were analysed for rates of hospital discharges for different population groups and by general practice.

There is a substantial variation in hospital discharge rates between general practices, but this is only partly accounted for by practice population characteristics. Furthermore while there is a strong social gradient in European admissions, this is much less true for Maori. There was also a wide variation between practices in the uptake of High Use Health Cards, special funding for frequent attenders at general practices and 'Care Plus' funding for patients with chronic conditions. Practice deprivation, ethnicity and age only explained a minor part of this variation.

The high rate of unexplained practice variation in chronic care management and hospitalisation rates, especially for Maori, is of concern. Further investigation of the causes of such variability is needed as afirst step in reducing hospitalisation.