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Posted on 02 Jun 2021

VAHI released our second Hospital acquired complications (HACs) report to public health services in early May 2021, with considerable feedback from health services driving changes since the first report was released in December 2020.

VAHI has appreciated the input and expert review from health services based on the first report. We have used these insights to update and guide development of this most recent HACs report.

As a result of the feedback, several updates were made including removal of subacute episodes and HAC4 (surgical complications requiring unplanned return to theatre) from the second report. We are hearing that the HAC4 measure inevitably captures more false positives than genuine cases of concern, due to the way it is currently defined in the national specifications. HAC4 data were also removed from the calculation of the “All HACs” summary measure. VAHI will work in partnership with other stakeholders on improving national specifications and data elements for HAC4.

This edition of the HACs report also includes an “In focus” section detailing the support VAHI provides to enable health services to understand and reduce their rates of HACs. This includes information on available support to validate and investigate results, improving coding quality via the use of Relative Indicators for Safety and Quality (RISQTM) tool and access to the Classification of Hospital Acquired Diagnoses (CHADx) System of Clinical Intelligence. A unit record level file and the specifications for the report are also provided to each health service to enable them to more deeply investigate cases highlighted in the report.

As per the usual approach for new measures, VAHI considers the first year of HACs reporting to be a “shadow” period, to enable health services to validate results, check underlying data, and build new measures into their own clinical governance processes.  

The next HACs report will be released to public health services by mid-July 2021. We look forward to sharing the insights with health services. Please continue to share your feedback to help us improve future editions of the report.

For more information on the HACs report, please contact Adina Hamilton, Acting Director, Health System Insights, via

Page last updated: 02 Jun 2021