Vitamin D testing patterns among general practitioners in a major Victorian primary health care service

To examine 25(OH)D testing patterns and frequency among general practitioners in a major community health service.

A clinical audit of patient records at a community health centre in Melbourne was undertaken. Patients aged 18 years and above were included. Univariate and multivariate logistic regression was used to examine the association between vitamin D testing and socio-demographic characteristics while Poisson regression was used for the frequency of testing.

There were 1,217 patients tested for serum 25(OH)D. The community health centre was served by 12 general practitioners and an infectious disease specialist. The odds of vitamin D testing showed a positive, albeit weak, association with age (OR 1.01, 95%CI 1.00-1.02, p<0.05), were higher among females than males (OR 1.42, 95%CI 1.18-1.70, p<0.05) and higher among migrants compared to non-migrants (OR 2.57, 95%CI 2.14-3.09, p<0.05). The frequency of testing was also higher among females than males (IRR 1.17, 95%CI 1.07-1.28, p<0.05) and higher among migrants than non-migrants (IRR 1.19, 95%CI 1.08-1.31, p<0.05).

Advancing age, being female and being a migrant were associated with an increased likelihood of vitamin D testing.

Development of evidence-based policies and guidelines are needed to manage over-testing of vitamin D in Australia. Studies that include health services from different areas are required to understand vitamin D testing patterns among the general practitioners.