daySupply - Calculating Days' Supply and Daily Dose of Prescriptions
Allows clinicians and researchers to compute daily dose
(and subsequently days' supply) for prescription refills using
the following methods: Fixed window, fixed tablet, defined
daily dose (DDD), and Random Effects Warfarin Days' Supply
(REWarDS). Daily dose is the computed dose that the patient
takes every day. For medications with fixed dosing (e.g. direct
oral anticoagulants) this is known and does not need to be
estimated. For medications with varying dose such as warfarin,
however, the daily dose should be assumed or estimated to allow
measurement of drug exposure. Days’ supply is the number of
days that patients’ supply of medication will last after each
prescription fill. Estimating days’ supply is necessary to
calculate drug exposure. The package computes days’ supply and
daily dose at both the prescription and patient levels. Results
at the prescription level are denoted with “-Rx-” and those at
patient level are denoted with “-Pt-”.