Cross-cultural Adaptation and Validation of the Medication Regimen Complexity Index Adapted to Spanish.

Background: The most widely used validated instrument to assess the complexity of medication regimens is the Medication Regimen Complexity Index (MRCI).

Objective: This study aimed to translate, adapt, and validate a reliable version of the MRCI adapted to Spanish (MRCI-E).

Methods: The cross-cultural adaptation process consisted of an independent translation by 3 clinical pharmacists and a backtranslation by 2 native English speakers.