Effectiveness of professional and patient-oriented strategies in reducing vitamin D and B12 test ordering in primary care: a cluster randomised intervention study

Saskia van Vugt*, Evelien de Schepper, Sanne van Delft, Nicolaas Zuithoff, Niek de Wit, Patrick Bindels

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review

4 Citations (Scopus)
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Background: Vitamin tests are increasingly ordered by GPs, but a clinical and evidence-based indication is often lacking. Harnessing technology (that is, decision support tools and redesigning request forms) have been shown to reduce vitamin requests. Aim: To investigate whether the number of vitamin tests may be reduced by providing a multi-level intervention programme based on training, monitoring, and feedback. Design & setting: This was a cluster randomised intervention study performed in 26 primary care health centres (>195 000 patients) in the Netherlands. The relative reduction in ordered vitamin D and B12 tests was determined after introduction of two de-implementation strategies (1 May 2017 to 30 April 2018). Method: Health centres randomised to de-implementation strategy 1 received education and benchmarking of their own vitamin test ordering behaviour every 3 months. Health centres in deimplementation strategy 2 received the same education and benchmarking, but supplemented with educational material for patients. Results: The number of vitamin D tests decreased by 23% compared to the 1-year pre-intervention period (1 May 2016 to 30 April 2017). For vitamin B12 tests an overall reduction of 20% was found. Provision of patient educational information showed additional value over training and benchmarking of GPs alone for vitamin D test ordering (10% extra reduction, odds ratio [OR] 0.88, 95% confidence interval [CI] = 0.83 to 0.92), but not for vitamin B12 ordering (4% extra reduction, OR 0.96, 95% CI = 0.91 to 1.02). Nationwide, this would result in over €3 200 000 in savings on healthcare expenditure a year. Conclusion: A structured intervention programme, including training and benchmarking of GPs regarding their diagnostic test ordering, resulted in a significant reduction in ordered vitamin tests. Additional information provision to patients resulted in a small but still relevant additional reduction. If implemented on a national level, a substantial cost saving could be achieved

Original languageEnglish
Pages (from-to)1-10
JournalBJGP Open
Issue number6
Publication statusPublished - 27 Oct 2021

Bibliographical note

Funding Information:
The authors would like to thank Sacha de Lathouder from STAR-shl Diagnostic Center for Primary Care, and Lara Harmans and Sanne van Delft from Saltro Diagnostic Center for Primary Care for their participation in the data collection. They would also like to thank Dr Alike van der Velden, from the Julius Center for Health Sciences and Primary Care of University Medical Center Utrecht, for her help with the study design, recruitment and ethical approval. The authors would also like to thank all included GPs for their enthusiastic participation during the intervention year

Publisher Copyright:
© 2021, The Authors


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