Exposure Ascertainment Module - Overview

The Exposure Ascertainment Module of T-Rx package aims to convert cleaned prescriptions (in long format) into prescribing episodes as longitudinal exposures.

The Motivation

Figure 1: Conceptual framework for Exposure Ascertainment Module

The construction of treatment episodes is a common approach to assess how long an individual is exposed to a certain medication longitudinally.

Ideally this can be established by looking at the treatment coverage of prescriptions - by merging consecutive if the periods of coverage were in overlap.

In real-world EHR records however, several challenges remain:

Coverage of prescriptions were often unavailable (e.g.: UK Biobank)
Treatment complexity in real-life settings, such as delays in follow-up and medication stockpiling

This module provides function to allow users to easily convert these prescriptions into longitudinal exposure (with allowance for real-life treatment complexities), for further visualization and study of treatment exposure.

We also aim to offer inferrence algorithms (e.g.: dosing frequency) for users to ascertain the treatment episodes of individuals.

Any questions?

Please post questions as an issue on the T-Rx GitHub repo here.

The T-Rx package is currently under beta testing. Most functions should have adequate documentation on possible errors.

Please kindly reach out to Chris Lo (chris.lowh@kcl.ac.uk) for feedback on documentation.