Rivaroxaban for the treatment of deep vein thrombosis and ...

Chi-square analyses were undertaken by the ERG which reported a p-value of 0.14, indicating no
significant difference, but the number of events may be too small to highlight an actual difference.
Whilst it is likely to be the case that the disparity in results were caused by chance alone, the clinical
impacts of a PE are more serious than that of a DVT, and it was thought prudent to highlight the
potential impact of any assumption that the ratio of PE to DVT was independent of treatment. This is
the subject of exploratory economic analysis later in the report.
Figure 2: Kaplan-Meier plot for VTE recurrence (primary efficacy outcome) in
EINSTEIN-DVT (reproduction of Figure 7, Page 55 of MS) 1
Subgroup analyses for DVT recurrence – EINSTEIN-DVT
A large number of subgroup analyses were presented in the report (Page 56, Figure 8, reproduced here
as Figure 3). Interestingly, whilst the MS suggests these were defined a priori, the ERG have not been
able to locate a description of these analyses in the protocol provided by the Manufacturer. 39 These
may be contained in the Statistical Analysis Plans, which were not included with the protocol. As
such, it is unclear whether the subgroup analyses were planned a priori.
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