Can patient safety indicators monitor medical and surgical care at New Zealand public hospitals?

Abstract

INTRODUCTION: Increasing interest has focused on the safety of hospital care. The AusPSIs are a set of indicators developed from Australian administrative data to reliably identify inpatient adverse events in hospitals. The main aim of this study was to explore the application of the AHRQ/AusPSIs to New Zealand administrative hospital data related to medical and surgical care. Variation over time and across hospitals were also considered for a subset of the more common indicators. METHOD: AHRQ/AusPSIs were adapted for use with New Zealand National Minimum Dataset administrative data for the period 2001-9. Crude positive event rates for each of the 16 indicators were assessed across New Zealand public hospitals. Variation over time for six more common indicators is presented using statistical control charts. Variation between hospitals was explored using rates adjusted for differences in patient variables including age, sex, ethnicity, rurality of residence, NZDep score and comorbidities. RESULTS: The AHRQ/AusPSIs were applied to New Zealand administrative hospital data and some 99,366 admissions were associated with a positive indicator event. However rates for some indicators were low (<1% of denominator admissions). Over the study period considerable variation in the rate of positive events was evident for the six most common indicators. Likewise there was substantial variation between hospitals in relation to risk adjusted positive event rates DISCUSSION: Patient safety indicators can be applied to New Zealand administrative hospital data. While infrequent rates hinder the use of some of the indicators, several could now be readily employed as warning flags to help monitor rates of adverse events at particular hospitals. In conjunction with other established or emerging tools, such as audit and trigger tools, the PSIs are now available to promote ongoing quality improvement activities in New Zealand hospitals.