Is vitamin D testing at a tertiary referral hospital consistent with guideline recommendations?

To determine if 25 hydroxyvitamin D (25OHD) testing at our tertiary referral hospital is consistent with guideline recommendations concerning the clinical indications for testing, the timing of repeat testing and utilisation of the test result, we conducted a retrospective audit of electronic laboratory and patient case records. We included adult inpatients and outpatients who had serum 25OHD measured during a randomly selected one-week audit period and who had patient case records available for detailed review. The audit sample comprised 184 serum 25OHD measurements (134 initial and 50 repeat tests). There were 81 (60%) initial and 15 (30%) repeat tests [96 (52%) overall] that were consistent with guideline recommendations concerning clinical indication, timing of repeat testing and utilisation of result. Almost half the 25 hydroxyvitamin D tests audited were potentially unnecessary and/or not utilised clinically. Improved adherence to guideline recommendations for 25 hydroxyvitamin D testing, utilisation of test results and enforcement of new indications for testing due to be introduced by Medicare Australia could result in significant cost savings without adversely affecting patient outcomes.