Reporting Adverse Drug Events: A Comparison of an Online Patient Tool Versus Telephone-Based Monitoring in Community Pharmacy Patients in the Netherlands

Background Adverse drug events (ADEs) are events occurring after the administration of a drug. Several authorities are involved in capturing these ADEs to improve pharmacovigilance. These ADEs are reported directly to healthcare professionals or via the telephone, online, or e-mail and are crucial for maintaining drug safety. Objective Patient-reported adverse drug events (ADEs) are collected using various tools, though not much is known with regard to the comparability of these different methodologies. It is known that telephone-based surveys result in a higher report rate, although it is not known if this has an effect on the type of ADEs that are reported. In this prospective study, we aimed to investigate if there are differences in the number, type, and severity of ADEs reported via telephone and online in an event monitoring setting. Methods Patients included in Dutch community pharmacies were asked whether they experienced any ADEs via telephone and online (Lareb Intensive Monitoring) surveys as part of the PREPARE study. The PREPARE study was a multicenter study, researching the effect of genotype-guided dosing on the incidence of clinically relevant adverse drug reactions. With the paired data acquired in the PREPARE study, we investigated differences in the number, type, and severity of the reported ADEs. Results Patients (N = 525) completed both the telephone and online surveys. Of the 525 patients who completed both surveys, 326 reported ADEs via telephone and 239 online. A visual comparison showed a similar distribution in the type of ADEs among the methods except for less commonly reported types of ADEs and cardiac disorders. The perceived severity of ADEs were proportionally reported as more severe during the telephone survey versus the online survey. Conclusions Our study showed a clear difference in the number of ADEs reported during telephone and online monitoring. Additionally, the differences in the type of ADEs and the severity distribution of both tools shows that the tools are not exchangeable (CT.gov identifier: NCT03093818).