More than two-dozen prescription drug-based risk scores are available for risk adjustment: A systematic review

Abstract

Objective: While several prescription drug-based risk indices have been developed, their design, performance, and application has not previously been synthesized.

Study design and setting: We searched Ovid MEDLINE, CINAHL and Embase from inception through March 3, 2020 and included studies that developed or updated a prescription drug-based risk index. Two reviewers independently performed screening and extracted information on data source, study population, cohort sizes, outcomes, study methodology and performance. Predictive performance was evaluated using C statistics for binary outcomes and R² for continuous outcomes. The PROSPERO ID for this review is CRD42020165498.

Results: Of 19,112 articles that were retrieved, 124 were full-text screened and 25 were included, each of which represented a de novo or updated drug-based index. The indices were customized to varied age groups and clinical populations and most commonly evaluated outcomes including mortality (36%), hospitalization (24%) and healthcare costs (24%). C statistics ranged from 0.62 to 0.92 for mortality and 0.59 to 0.72 for hospitalization, while adjusted R² for healthcare costs ranged from 0.06 to 0.62. Seven of the 25 risk indices included used global drug classification algorithms.

Conclusions: More than two-dozen prescription drug-based risk indices have been developed and they differ significantly in design, performance and application.

Keywords: Administrative healthcare data; Comorbidity scores; Pharmacy data; Prescription drugs; Risk index; Systematic review.