For patients for whom 12-month follow-up information
was unavailable, data were included to
the date of their last documented follow-up and
were censored at that time. The CLARITY Research
Group data analyst remained unaware of
the treatment-group assignments while conducting
the primary analyses.
Using Cox regression stratified according to
fracture grade (I or II vs. III) and study center,
we first conducted a time-to-event analysis of
the main effects with respect to solution and
pressure and the interaction between the two
with regard to the reoperation rate. If the interaction
was significant, we planned to explore
the nature of the effect modification.