“Book Music” Representation for Temporal Data, as a Part of the Feature Extraction Process: A Novel Approach to Improve the Handling of Time-Dependent Data in Secondary Use of Healthcare Structured Data

Abstract

Book music is extensively used in street organs. It consists of thick cardboard, containing perforated holes specifying the musical notes. We propose to represent clinical time-dependent data in a tabular form inspired from this principle. The sheet represents a statistical individual, each row represents a binary time-dependent variable, and each hole denotes the “true” value. Data from electronic health records or nationwide medical-administrative databases can then be represented: demographics, patient flow, drugs, laboratory results, diagnoses, and procedures. This data representation is suitable for survival analysis (e.g., Cox model with repeated outcomes and changing covariates) and different types of temporal association rules. Quantitative continuous variables can be discretized, as in clinical studies. The “book music” approach could become an intermediary step in feature extraction from structured data. It would enable to better account for time in analyses, notably for historical cohort analyses based on healthcare data reuse.

Data Management for Health Data Reuse: Proposal of a Standard Workflow and a R Tutorial with Jupyter Notebook

“…Indeed, in these approaches, data are always multidimensional, heterogeneous and time-dependent. Several operations are generally realized to select the relevant patients across the cohort, combine information from multiple tables, add new variables if needed, and reconstruct a consolidated unique table to answer the research question [4]- [6]. These operations are difficult to perform manually, due to the large number of records and are implemented with a computer program, such as R, python or SQL.…”