Test ordering in an evidence free zone: Rates and associations of Australian general practice trainees' vitamin D...

Indiscriminate health screening is increasingly seen as being problematic. In particular, vitamin D testing rates are increasing rapidly despite recommendations against population screening. The purpose of this study was to determine the level of vitamin D testing among family practice/general practitioner (GP) trainees and to establish associations of this testing.

Cross-sectional analysis of data from the ReCEnT (Registrars Clinical Encounters in Training) cohort study. The setting was GP practices in four Australian states. Data from 60 consecutive consultations per trainee were recorded each 6-month training term (up to four terms).

Vitamin D tests were ordered in 726 (1.0%) of encounters (n = 69 412). Vitamin D test ordering was significantly associated with patients being older, female and non-English speaking. Trainees were more likely to test if they worked in a completely bulk-billing practice (i.e. a practice without any patient payment), if more problems were dealt with, more pathology tests were ordered in the consultation and if a lipid profile was ordered. They were less likely to test if they sought in-consultation advice or information. The most common reasons for testing were 'check-up' and 'health maintenance'.

In this first report of associations of vitamin D testing in the GP setting, we found that non-targeted vitamin D testing (testing inconsistent with current guidelines) is widespread in GP trainees' practice. Adoption of more rational testing approaches is needed.