Tracing a roadmap for vitamin B₁₂ testing using the health technology assessment approach.

In our hospital, we are currently working to manage the appropriateness of vitamin B₁₂ (B12) testing. Unfortunately, the classic evidence-based approach is unhelpful in this process and meta-analyzing data on the accuracy of this marker for cobalamin deficiency detection is misleading due to the lack of reference diagnostic methods. The approach currently proposed by the Health Technology Assessment (HTA) enables us to tackle the issue of B₁₂ requests as a "healthcare" problem by considering the position of stakeholders involved in ordering, performing, interpreting the test, and receiving its results. Clinical expectations, methodological issues, and ethical aspects concerning the performance of the test can aid us in providing more guidance on the use of this marker. By building such structured information, hemodialysis patients and pregnant women have emerged as those groups preferentially requiring B₁₂ testing, as it may potentially improve the clinical outcome. To avoid misinterpretation of B₁₂ results more care should be taken in considering its biochemical and biological features, as well as the analytical issues. Spurious values obtained by current automated immunoassays may reflect suboptimal pre-analytical steps as well as known interfering conditions. Furthermore, the harmonization of results by available methods is still a far-reaching goal and the approach to interpret an individual's results should be improved. Tracing a roadmap for B₁₂ testing by exploiting the HTA model to balance the stakeholders' claims and maximizing the patient's outcome may help to manage the marker demand.