Estimating rotavirus gastroenteritis hospitalisations by using hospital episode statistics before and after the introduction of rotavirus vaccine in Australia

► Coding and testing patterns affect rotavirus burden and vaccine impact assessments. ► Only 36% of acute gastroenteritis hospitalisations had rotavirus stool testing. ► Rotavirus ICD code had low sensitivity (62%) to detect lab confirmed cases. ► Adjusted estimates were 6-fold higher than identified by rotavirus code only. ► Direct and adjusted methods gave similar reductions (over 65%) following vaccination.