Fully independent validation of the Matrix-INI, IMEPAG-group, MERIS instruments for predicting preventable drug-related incidents of hospitalized patients with infectious diseases

Validate and compare three prescription-related incident prediction instruments (Matrix-INI, IMEPAG-group, MERIS) in hospitalized patients with infectious disease. Observational follow-up (cohort) study enrolling adults from June 2019 to March 2020, with no prior care from the clinical pharmacist. Matrix-INI, MERIS, and IMEPAG-group instruments assessing preventable drug-related incidents (PDRI) were applied at ward admission and once a week. The outcome of interest was clinically relevant PDRI. For every participant at every time of analysis, the instruments scores were retrieved, and validation was estimated through calibration (slope, intercept), discrimination indexes, and reclassification indexes. 219 patients were screened, and 212 were included. PDRI affected 78.77% of participants. “Anticoagulants” was the strongest predictor. Discrimination of all instruments was always low. (area under ROC curve < 0.70); and weekly performance was insufficient. No reclassification improvement was observed. Matrix-INI, IMEPAG-group assigned lower risks despite PDRI. Discrimination increases slightly every week, with a corresponding calibration loss. Models lacked sufficient predictive performance, pointing to a need for a specific PDRI prediction tool for this population. Empirically developed instruments, such as Matrix-INI, often exhibit poor performance. Regular risk assessments during hospitalization are crucial for dynamic prioritization in clinical pharmacy, as PDRI risk may change over time.