To the Editor: Dilip V. Jeste, M.D., et al. (1) provided good evidence for the use of risperidone to reduce psychotic symptoms and to prevent and treat tardive dyskinesia in elderly patients with moderate to severe dementia. However, there are problems with their methods, most notably with their analysis of the patients who did not complete the study. They state that of the 330 patients enrolled in an open-label trial of risperidone, 133 (40.3%) completed the 12-month trial. Few reasons were given for patients dropping out, except that nine patients stopped taking risperidone because of extrapyramidal symptoms. The remaining 188 (57.0%) remained unaccounted for at the end of the study.