Modelling the cost effectiveness of interferon beta and glatiramer acetate in the management of multiple sclerosisBMJ 2007; 334 doi: http://dx.doi.org/10.1136/bmj.39155.488704.BE (Published 22 March 2007) Cite this as: BMJ 2007;334:0-b
During further recent study, the authors of this paper, J Chilcott and colleagues (BMJ 2003;326:522-5, doi: 10.1136/bmj.326.7388.522), found a coding error in the model that was not identified in any of the review procedures in the original project. The effect of the error, say the authors, was that the model allocated treatment benefits to patients who had stopped treatment. The revised model implements correctly an assumption that patients who stop therapy revert to a natural course of disease progression.
The authors have rerun the analysis using the correct coding, and a revised version of the table that was published in the abridged article (which was table 2 in the full article) is available at www.bmj.com/cgi/data/326/7388/522/DC1/1. The revised data indicate higher costs per quality adjusted life year for interferon beta and glatiramer acetate than given in the published article. This should be borne in mind when reading other sections of the article (the results in the abstract and in the main text; the figure showing cost effectiveness acceptability curves; and the “What this study adds” section of the summary box). The authors state that the coding error and revised results do not affect the conclusions of their paper.