The study included retrospectively identified residents of a long-term care facility who were over age 50 years, received VPA between 1990 and 2008, and had at least 1 recorded platelet count.

• 这项回顾性研究包括了50岁以上的长期疗养所的老人。他们在1990年到2008年间接受VPA治疗，并且至少有一次有记录的血小板计量。