Skip to main content

Research Repository

See what's under the surface

A Bayesian elicitation of veterinary beliefs regarding systemic dry cow therapy: variation and importance for clinical trial design

Higgins, H.M.; Dryden, Ian L.; Green, Martin J.

Authors

H.M. Higgins

Ian L. Dryden

Martin J. Green martin.green@nottingham.ac.uk



Abstract

The two key aims of this research were: (i) to conduct a probabilistic elicitation to quantify the variation in veterinarians’ beliefs regarding the efficacy of systemic antibiotics when used as an adjunct to intra-mammary dry cow therapy and (ii) to investigate (in a Bayesian statistical framework) the strength of future research evidence required (in theory) to change the beliefs of practising veterinary surgeons regarding the efficacy of systemic antibiotics, given their current clinical beliefs.

The beliefs of 24 veterinarians in 5 practices in England were quantified as probability density functions. Classic multidimensional scaling revealed major variations in beliefs both within and between veterinary practices which included: confident optimism, confident pessimism and considerable uncertainty. Of the 9 veterinarians interviewed holding further cattle qualifications, 6 shared a confidently pessimistic belief in the efficacy of systemic therapy and whilst 2 were more optimistic, they were also more uncertain. A Bayesian model based on a synthetic dataset from a randomised clinical trial (showing no benefit with systemic therapy) predicted how each of the 24 veterinarians’ prior beliefs would alter as the size of the clinical trial increased, assuming that practitioners would update their beliefs rationally in accordance with Bayes’ theorem.

The study demonstrated the usefulness of probabilistic elicitation for evaluating the diversity and strength of practitioners’ beliefs. The major variation in beliefs observed raises interest in the veterinary profession's approach to prescribing essential medicines. Results illustrate the importance of eliciting prior beliefs when designing clinical trials in order to increase the chance that trial data are of sufficient strength to alter the clinical beliefs of practitioners and do not merely serve to satisfy researchers.

Journal Article Type Article
Publication Date Sep 15, 2012
Journal Preventive Veterinary Medicine
Print ISSN 0167-5877
Electronic ISSN 0167-5877
Publisher Elsevier
Peer Reviewed Peer Reviewed
Volume 106
Issue 2
Institution Citation Higgins, H., Dryden, I. L., & Green, M. J. (2012). A Bayesian elicitation of veterinary beliefs regarding systemic dry cow therapy: variation and importance for clinical trial design. Preventive Veterinary Medicine, 106(2), doi:10.1016/j.prevetmed.2012.01.017
DOI https://doi.org/10.1016/j.prevetmed.2012.01.017
Publisher URL http://www.sciencedirect.com/science/article/pii/S0167587712000359
Copyright Statement Copyright information regarding this work can be found at the following address: http://creativecommons.org/licenses/by/4.0

Files

Line_54_A_Bayesian_elicitation_of_veterinary_beliefs.pdf (626 Kb)
PDF

Copyright Statement
Copyright information regarding this work can be found at the following address: http://creativecommons.org/licenses/by/4.0





Downloadable Citations