Intervention fidelity and process outcomes of medication reviews including post-discharge follow-up in older hospitalized patients: Process evaluation of the MedBridge trial

What is known and objective Drug-related problems (DRPs) are a growing healthcare burden worldwide. In an ongoing cluster-randomized controlled trial in Sweden (MedBridge), comprehensive medication reviews (CMRs) including post-discharge follow-up have been conducted in older hospitalized patients to prevent and solve DRPs. As part of a process evaluation of the MedBridge trial, this study aimed to assess the intervention fidelity and process outcomes of the trial's interventions. Methods For intervention delivery, the percentage of patients that received intervention components was calculated per study group. Process outcomes, measured in about one-third of all intervention patients, included the following: the number of identified medication discrepancies, DRPs and recommendations to solve DRPs, correction rate of discrepancies, and implementation rate of recommendations. Results and discussion The MedBridge trial included 2637 patients (mean age: 81 years). The percentage of intervention patients (n = 1745) that received the intended intervention components was 94%-98% during admission, and 40%-81% upon and after discharge. The percentage of control patients (n = 892) that received at least one unintended intervention component was 15%. On average, 1.1 discrepancies and 2.0 DRPs were identified in 652 intervention patients. The correction and implementation rates were 79% and 73%, respectively. Stop medication was the most frequently implemented recommendation (n = 293) and 77% of the patients had at least one corrected discrepancy or implemented recommendation. What is new and conclusion The intervention fidelity within the MedBridge trial was high for CMRs during hospital stay and lower for intervention components upon and after discharge. The high prevalence of corrected discrepancies and implemented recommendations may explain potential effects of CMRs in the MedBridge trial.