RT Journal Article SR Electronic T1 29 Vitamin D test ordering practices of australian general practitioners between 2007 and 2017: evidence from electronic health records JF BMJ Evidence-Based Medicine JO BMJ EBM FD BMJ Publishing Group Ltd SP A21 OP A21 DO 10.1136/bmjebm-2019-POD.43 VO 24 IS Suppl 2 A1 Gorkem Sezgin A1 Andrew Georgiou YR 2019 UL http://ebm.bmj.com/content/24/Suppl_2/A21.1.abstract AB Objectives Concerns of over-testing of vitamin D tests were raised when a study Bilinski and Boyages reported an increase in Medicare claimed vitamin D tests by over 10-fold from 2006 to 2010 across Australia, and 94-fold from 2000 to 2010. Most vitamin D tests during this period were ordered by general practitioners. Our aim was to determine the procedures and diagnoses associated with the utilisation of vitamin D testing among Australian general practitioners and describe the change in its use throughout the last decade.Methods We conducted a retrospective observational study based on secondary data analysis of electronic health record data from Australian general practices. Our study included data from three Primary Health Networks across Victoria: Gippsland, Eastern Melbourne, and South Eastern Melbourne, which was sourced from the Population Level Analysis and Reporting (POLAR) Data Space. Procedures containing the most vitamin D test orders were identified and generalised linear modelling containing the socio-demographic parameters gender, age, Primary Health Network, season, quarter of the year, year, and socio-economic status were utilised to estimate the proportion of test requests containing vitamin D for each procedure each year.Results Vitamin D testing was most frequently associated with general procedures, including: health check-up, pregnancy/antenatal care, and pap-smear. Among the top reasons for ordering vitamin D tests, osteoporosis was the only condition in compliance with recommended guidelines. While vitamin D testing was rarely ordered for antenatal care and pregnancy during 2007, by 2013 it was present in over 40% of test requests. Pap-smear testing were accompanied by vitamin D tests in over 11% of test requests after 2010: a 7-fold increase from 2007. In 2013, almost 50% of test requests for check-up contained vitamin D tests: an increase by over 5-fold from 2007. A similar pattern of vitamin D testing for fatigue was observed, with a peak of over 50% of test requests containing vitamin D in 2012. Although a reduction in vitamin D testing for general procedures occurred around 2015, its use has since been increasing. Vitamin D testing for osteoporosis remained relatively constant between 2007 and 2017, fluctuating between 30% and 40%.Conclusion Our study demonstrates an increase in vitamin D testing in recent years for general procedures. There is a strong possibility of over-utilisation of vitamin D testing which is unlikely to discontinue without intervention. We recommend conducting interventions promoting awareness and adherence to guidelines in order to reduce unnecessary or excessive testing.