4. Measurement methodology in PRO research

1.3. Points to consider when adapting PROMs

Users might be tempted to make some changes to established measures by modifying the original design of the approaches of the instruments/tools. This may be something that seems harmless, like translating the tool into a local language or using an electronic questionnaire instead of a paper-based one. However simple modifications to tools like these may significantly change the performance and ability to interpret results. Thorough efforts must go into re-validating and testing a PRO instrument when changing its use from what it was originally intended to measure, which would lead to a new PROM (e.g., in a different therapeutic field, but also when using a different approach (e.g., moving from paper to ePROM).