K. R. Lees, I. Sim, C. J. Weir, L. Erwin, C. McAlpine, J. Rodger, T. Jones, K. W. Muir, H. W. Fraser, R. S. MacWalter, A. Dorward, G. Gorman, A. Hussein, L. Quate, S. Ghosh, K. Musbahi, U. Rutherford, W. Brooks, J. Hamilton, T. G. Robinson, M. S. Ali, L. Gogola, L. Al-Dhahir, S. Gerrie, G. S. Rai, J. Horsley, M. Salehin, D. J. Walker, D. G. Grosset, A. Dunn, S. Manthri, G. Woodman, M. Goertler, T. Treuheit, C. W. Wallesch, A. Brown, D. F. D'Costa, E. V. McLelland, J. Sinclair, K. Boyle, A. Hendry, Prism Study Grp



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Qjm-an International Journal of Medicine

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Background: Identifying the appropriate long-term anti-thrombotic therapy following acute ischaemic stroke is a challenging area in which computer-based decision support may provide assistance. Aim: To evaluate the influence on prescribing practice of a computer-based decision support system (CDSS) that provided patient-specific estimates of the expected ischaemic and haemorrhagic vascular event rates under each potential anti-thrombotic therapy. Design: Cluster-randomized controlled trial. Methods: We recruited patients who presented for a first investigation of ischaemic stroke or TIA symptoms, excluding those with a poor prognosis or major contra indication to anticoagulation. After observation of routine prescribing practice (6 months) in each hospital, centres were randomized for 6 months to either control (routine practice observed) or intervention (practice observed while the CDSS provided patient-specific information). We compared, between control and intervention centres, the risk reduction (estimated by the CDSS) in ischaemic and haemorrhagic vascular events achieved by long-term anti-thrombotic therapy, and the proportions of subjects prescribed the optimal therapy identified by the CDSS. Results: Sixteen hospitals recruited 1952 subjects. When the CDSS provided information, the mean relative risk reduction attained by prescribing increased by 2.7 percentage units (95%CI -0.3 to 5.7) and the odds ratio for the optimal therapy being prescribed was 1.32 (0.83 to 1.80). Some 55% (5/9) of clinicians believed the CDSS had influenced their prescribing. Conclusions: Cluster-randomized trials provide excellent frameworks for evaluating novel clinical management methods. Our CDSS was feasible to implement and acceptable to clinicians, but did not substantially influence prescribing practice for anti-thrombotic drugs after acute ischaemic stroke.