The ISPOR Task Force on measurement comparability between modes of data collection for patient-reported outcome measures (PROMs) has updated the good practice recommendations from the 2009 ISPOR electronic patient-reported outcome and 2014 patient-reported outcome mixed modes Good Research Practices Task Force reports in light of accumulated evidence of measurement comparability among different modes of PROM data collection. Furthermore, with the increasing use of electronic formats of clinical outcome assessments in clinical trials and the US Food and Drug Administration's encouragement of electronic data collection, this new task force report provides stakeholders with best practice recommendations reflecting the current body of evidence and enables them to respond to future developments in research and technology. This task force recommends an evidence-based approach to determine whether new research is needed to evaluate measurement comparability for a given questionnaire or technology. The suitability of existing evidence depends upon whether it satisfactorily demonstrates that the change in data collection mode has not affected the PROM's measurement properties. In cases where sufficient evidence of measurement comparability exists and best practices for faithful migration are followed, this task force concludes that further testing of measurement comparability among the data collection modes is unnecessary, including cases of "mixing modes" within clinical trials such as bring your own device designs.