What do patients know about their newly prescribed medication: Application of a novel knowledge index.

Objective: The present study aimed to evaluate patients' knowledge about their newly prescribed medications, contributing factors, and preferred sources of medication-related information.

Methods: A cross-sectional study using an online survey was conducted among 931 customers of a mail-order pharmacy. Medication-related knowledge was examined using a novel knowledge index (KI) assessing medication dosage, indication, time of administration, and side effects.