The efficacy of rivastigmine was also assessed in terms of the proportion of subjects in whom cognitive function was sustained or improved from baseline after 6 months of treatment (mean change from baseline in ADAS-cog>0). In total, 46% of the subjects treated with rivastigmine either improved or showed no deterioration, compared with 9% of subjects treated with placebo (OC population; p < 0.001). The respective figures in the ITT-LOCF population were 44% for rivastigmine and 7% for placebo (p = 0.001).