Adherence to ribavirin is one factor that is critically important in the treatment of hepatitis C virus infection. However, ribavirin can be associated with clinically significant hemolytic anemia resulting in dose modifications in up to one-quarter of patients. Currently, baseline predictors of considerable anemia are not sufficiently discriminating for routine therapeutic intervention. The objective of this analysis was to elucidate baseline and on-treatment factors predictive of a considerable hemoglobin drop at week 4
