Geographic disparities in the utilisation of computed tomography scanning services in southern New Zealand.

Most secondary care health services in New Zealand, including computed tomography (CT) scanners, are concentrated in urban centres. Little is known about the access rural patients have to these services. The aim of this research was to determine whether there was geographic variation in the utilisation of CT across the southern part of the South Island and if present to measure the magnitude. Quantitative analysis of public hospital data for CTs over two twelve month periods (2007/08 and 2010) showed that residents of urban base hospital catchment areas were 1.6 times more likely to access CT services than residents of the catchment areas of remote rural hospitals. Similar disparities were present when the analysis was limited to the ≥70 yrs age group. The disparities were present regardless of the referral source or the type of scan but were greatest for emergency department referrals, head scans and CT pulmonary angiograms. Further research is needed to determine the causes of these differences and whether they result in differences in health outcomes.