Methods
SECONDARY
The CRISTAL trial was approved by the Sydney Local Health District human research ethics committee and by all relevant local ethic committees prior to commencement. All patients provided consent for provision and use of their data, and enrolled patients provided consent to be contacted postoperatively to collect outcome data for the primary study. A waiver of consent was granted by each ethics committee for the use of either study drug, as both drugs were considered common practice throughout Australia for prophylaxis prior to trial commencement. This secondary analysis follows the Consolidated Standards of Reporting Trials (